Moved self-check framework into libnautilus. Added functions so each

check will report if it fails instead of just aborting.

Added new functions to manage a string that specifies a color or
gradient, and added tests for the new functions.

29 files changed, 2044 insertions, 169 deletions

diff --git a/ChangeLog-20000414 b/ChangeLog-20000414
index 96c43bab1..121c3a000 100644
--- a/ChangeLog-20000414
+++ b/ChangeLog-20000414
@@ -1,3 +1,30 @@
+2000-01-06  Darin Adler  <darin@eazel.com>
+
+	* libnautilus/Makefile.am,
+	libnautilus/nautilus-lib-self-check-functions.c,
+	libnautilus/nautilus-lib-self-check-functions.h,
+	libnautilus/nautilus-self-checks.c,
+	libnautilus/nautilus-self-checks.h, src/Makefile.am,
+	src/nautilus-self-check-functions.c,
+	src/nautilus-self-check-functions.h, src/nautilus-self-checks.c,
+	src/nautilus-self-checks.h, src/ntl-main.c (main),
+	src/file-manager/fm-directory.c,
+	src/file-manager/fm-vfs-directory.c: Moved self-check framework
+	into libnautilus. Added functions so each check will report if it
+	fails instead of just aborting.
+
+	* src/gdk-extensions.c, src/gdk-extensions.h
+	(nautilus_gradient_new, nautilus_gradient_is_gradient,
+	nautilus_gradient_get_start_color_spec,
+	nautilus_gradient_get_end_color_spec,
+	nautilus_gradient_is_horizontal,
+	nautilus_gradient_set_left_color_spec,
+	nautilus_gradient_set_top_color_spec,
+	nautilus_gradient_set_right_color_spec,
+	nautilus_gradient_set_bottom_color_spec): Added new functions to
+	manage a string that specifies a color or gradient, and added
+	tests for the new functions.
+
 2000-01-06  John Sullivan  <sullivan@eazel.com>
 
 	* src/ntl-app.h: src/ntl-app.c: (nautilus_app_exiting):
diff --git a/libnautilus-extensions/Makefile.am b/libnautilus-extensions/Makefile.am
index 719d7d76d..dc583e7f4 100644
--- a/libnautilus-extensions/Makefile.am
+++ b/libnautilus-extensions/Makefile.am
@@ -23,6 +23,8 @@ libnautilusinclude_HEADERS=			\
 	gtkscrollframe.h			\
 	nautilus.h				\
 	nautilus-file-utilities.h		\
+	nautilus-lib-self-check-functions.c	\
+	nautilus-self-checks.c			\
 	ntl-content-view-client.h		\
 	ntl-meta-view-client.h			\
 	ntl-view-client.h
@@ -35,6 +37,8 @@ libnautilus_la_SOURCES=$(nautilus_idl_sources)	\
 	gtkflist.c				\
 	gtkscrollframe.c			\
 	nautilus-file-utilities.c		\
+	nautilus-lib-self-check-functions.c	\
+	nautilus-self-checks.c			\
 	ntl-content-view-client.c		\
 	ntl-meta-view-client.c			\
 	ntl-view-client.c			\
diff --git a/libnautilus-extensions/gdk-extensions.c b/libnautilus-extensions/gdk-extensions.c
index 0f3184f3e..8f145b5b6 100644
--- a/libnautilus-extensions/gdk-extensions.c
+++ b/libnautilus-extensions/gdk-extensions.c
@@ -28,7 +28,9 @@
 
 #include "gdk-extensions.h"
 
-#include "../src/nautilus-self-check-functions.h"
+#include "nautilus-lib-self-check-functions.h"
+
+#include <string.h>
 
 #define GRADIENT_BAND_SIZE 4
 
@@ -178,30 +180,329 @@ nautilus_interpolate_color (gdouble ratio,
 	interpolated_color->blue = start_color->blue * (1.0 - ratio) + end_color->blue * ratio;
 }
 
+/**
+ * nautilus_gradient_new
+ * @start_color: Color for the top or left.
+ * @end_color: Color for the bottom or right.
+ * @is_horizontal: Direction of the gradient.
+ *
+ * Create a string that combines the start and end colors along
+ * with the direction of the gradient in a standard format.
+ */
+char *
+nautilus_gradient_new (const char *start_color,
+		       const char *end_color,
+		       gboolean is_horizontal)
+{
+	g_return_val_if_fail (start_color != NULL, g_strdup (""));
+	g_return_val_if_fail (end_color != NULL, g_strdup (""));
+	g_return_val_if_fail (is_horizontal == FALSE || is_horizontal == TRUE, g_strdup (""));
+
+	/* Handle the special case where the start and end colors are identical.
+	   Handle the special case where the end color is an empty string.
+	*/
+	if (strcmp(start_color, end_color) == 0 || end_color[0] == '\0')
+		return g_strdup (start_color);
+
+	/* Handle the special case where the start color is an empty string. */
+	if (start_color[0] == '\0')
+		return g_strdup (end_color);
+	
+	/* Handle the general case. */
+	return g_strconcat (start_color, "-", end_color, is_horizontal ? ":h" : NULL, NULL);
+}
+
+/**
+ * nautilus_gradient_is_gradient
+ * @gradient_spec: A gradient spec. string.
+ *
+ * Return true if the spec. specifies a gradient instead of a solid color.
+ */
+gboolean
+nautilus_gradient_is_gradient (const char *gradient_spec)
+{
+	g_return_val_if_fail (gradient_spec != NULL, FALSE);
+
+	return strchr (gradient_spec, '-') != NULL;
+}
+
+static char *
+nautilus_gradient_strip_trailing_direction_if_any (const char *gradient_spec)
+{
+	size_t length;
+
+	g_return_val_if_fail (gradient_spec != NULL, g_strdup (""));
+
+	length = strlen (gradient_spec);
+	if (length >= 2 && gradient_spec[length - 2] == ':'
+	    && (gradient_spec[length - 1] == 'v' || gradient_spec[length - 1] == 'h'))
+		length -= 2;
+
+	return g_strndup (gradient_spec, length);
+}
+
+/**
+ * nautilus_gradient_get_start_color_spec
+ * @gradient_spec: A gradient spec. string.
+ *
+ * Return the start color.
+ * This may be the entire gradient_spec if it's a solid color.
+ */
+char *
+nautilus_gradient_get_start_color_spec (const char *gradient_spec)
+{
+	const char *separator;
+	
+	g_return_val_if_fail (gradient_spec != NULL, g_strdup (""));
+	
+	separator = strchr (gradient_spec, '-');
+	if (separator == NULL)
+		return nautilus_gradient_strip_trailing_direction_if_any (gradient_spec);
+
+	return g_strndup (gradient_spec, separator - gradient_spec);
+}
+
+/**
+ * nautilus_gradient_get_end_color_spec
+ * @gradient_spec: A gradient spec. string.
+ *
+ * Return the end color.
+ * This may be the entire gradient_spec if it's a solid color.
+ */
+char *
+nautilus_gradient_get_end_color_spec (const char *gradient_spec)
+{
+	const char *separator;
+
+	g_return_val_if_fail (gradient_spec != NULL, g_strdup (""));
+
+	separator = strchr (gradient_spec, '-');
+	return nautilus_gradient_strip_trailing_direction_if_any
+		(separator != NULL ? separator + 1 : gradient_spec);
+}
+
+/* Do the work shared by all the set_color_spec functions below. */
+static char *
+nautilus_gradient_set_edge_color (const char *gradient_spec,
+				  const char *edge_color,
+				  gboolean is_horizontal,
+				  gboolean change_end)
+{
+	char *opposite_color;
+	char *result;
+
+	g_return_val_if_fail (gradient_spec != NULL, g_strdup (""));
+	g_return_val_if_fail (edge_color != NULL, g_strdup (gradient_spec));
+
+	/* Get the color from the existing gradient spec. for the opposite
+	   edge. This will parse away all the stuff we don't want from the
+	   old gradient spec.
+	*/
+	opposite_color = change_end
+		? nautilus_gradient_get_start_color_spec (gradient_spec)
+		: nautilus_gradient_get_end_color_spec (gradient_spec);
+
+	/* Create a new gradient spec. The nautilus_gradient_new function handles
+	   some special cases, so we don't have to bother with them here.
+	*/
+	result = nautilus_gradient_new (change_end ? opposite_color : edge_color,
+					change_end ? edge_color : opposite_color,
+					is_horizontal);
+
+	g_free (opposite_color);
+
+	return result;
+}
+
+/**
+ * nautilus_gradient_set_left_color_spec
+ * @gradient_spec: A gradient spec. string.
+ * @left_color: Color spec. to replace left color with.
+ *
+ * Changes the left color to what's passed in.
+ * This creates a horizontal gradient.
+ */
+char *
+nautilus_gradient_set_left_color_spec (const char *gradient_spec,
+				       const char *left_color)
+{
+	return nautilus_gradient_set_edge_color (gradient_spec, left_color, TRUE, FALSE);
+}
+
+/**
+ * nautilus_gradient_set_top_color_spec
+ * @gradient_spec: A gradient spec. string.
+ * @top_color: Color spec. to replace top color with.
+ *
+ * Changes the top color to what's passed in.
+ * This creates a vertical gradient.
+ */
+char *
+nautilus_gradient_set_top_color_spec (const char *gradient_spec,
+				      const char *top_color)
+{
+	return nautilus_gradient_set_edge_color (gradient_spec, top_color, FALSE, FALSE);
+}
+
+/**
+ * nautilus_gradient_set_right_color_spec
+ * @gradient_spec: A gradient spec. string.
+ * @right_color: Color spec. to replace right color with.
+ *
+ * Changes the right color to what's passed in.
+ * This creates a horizontal gradient.
+ */
+char *
+nautilus_gradient_set_right_color_spec (const char *gradient_spec,
+					const char *right_color)
+{
+	return nautilus_gradient_set_edge_color (gradient_spec, right_color, TRUE, TRUE);
+}
+
+/**
+ * nautilus_gradient_set_bottom_color_spec
+ * @gradient_spec: A gradient spec. string.
+ * @bottom_color: Color spec. to replace bottom color with.
+ *
+ * Changes the bottom color to what's passed in.
+ * This creates a vertical gradient.
+ */
+char *
+nautilus_gradient_set_bottom_color_spec (const char *gradient_spec,
+					 const char *bottom_color)
+{
+	return nautilus_gradient_set_edge_color (gradient_spec, bottom_color, FALSE, TRUE);
+}
+
 #if ! defined (NAUTILUS_OMIT_SELF_CHECK)
 
-static void
-self_check_interpolate(gdouble ratio,
-		       gushort r1, gushort g1, gushort b1,
-		       gushort r2, gushort g2, gushort b2,
-		       gushort r3, gushort g3, gushort b3)
+#include <stdio.h>
+
+static GdkColor
+nautilus_self_check_interpolate (gdouble ratio,
+				 gushort r1, gushort g1, gushort b1,
+				 gushort r2, gushort g2, gushort b2)
 {
-	GdkColor start_color = { 0, r1, g1, b1 };
-	GdkColor end_color = { 0, r2, g2, b2 };
+	GdkColor start_color;
+	GdkColor end_color;
 	GdkColor interpolated_color;
-	nautilus_interpolate_color(ratio, &start_color, &end_color, &interpolated_color);
-	g_assert(interpolated_color.red == r3);
-	g_assert(interpolated_color.red == g3);
-	g_assert(interpolated_color.red == b3);
+
+	start_color.red = r1;
+	start_color.green = g1;
+	start_color.blue = b1;
+
+	end_color.red = r2;
+	end_color.green = g2;
+	end_color.blue = b2;
+
+	nautilus_interpolate_color (ratio, &start_color, &end_color, &interpolated_color);
+
+	return interpolated_color;
 }
 
 void
-self_check_gdk_extensions (void)
+nautilus_self_check_gdk_extensions (void)
 {
-	self_check_interpolate(0.0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
-	self_check_interpolate(0.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF, 0, 0, 0);
-	self_check_interpolate(0.5, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF, 0x7FFF, 0x7FFF, 0x7FFF);
-	self_check_interpolate(1.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF);
+	/* nautilus_interpolate_color */
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0, 0, 0).red, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0, 0, 0).green, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0, 0, 0).blue, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).red, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).green, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).blue, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.5, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).red, 0x7FFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.5, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).green, 0x7FFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.5, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).blue, 0x7FFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (1.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).red, 0xFFFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (1.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).green, 0xFFFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (1.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).blue, 0xFFFF);
+
+	/* nautilus_fill_rectangle */
+	/* Make a GdkImage and fill it, maybe? */
+
+	/* nautilus_fill_rectangle_with_color */
+
+	/* nautilus_fill_rectangle_with_gradient */
+
+	/* nautilus_gradient_new */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("", "", FALSE), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("a", "b", FALSE), "a-b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("a", "b", TRUE), "a-b:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("a", "a", FALSE), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("a", "a", TRUE), "a");
+
+	/* nautilus_gradient_is_gradient */
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient (""), FALSE);
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient ("-"), TRUE);
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient ("a"), FALSE);
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient ("a-b"), TRUE);
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient ("a-b:h"), TRUE);
+
+	/* nautilus_gradient_get_start_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec (""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("-"), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a-b"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a-"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("-b"), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:h"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:v"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:c"), "a:c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:-b"), "a:");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:-b:v"), "a:");
+
+	/* nautilus_gradient_get_end_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec (""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("-"), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a-b"), "b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a-"), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("-b"), "b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:h"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:v"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:c"), "a:c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:-b"), "b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:-b:v"), "b");
+
+	/* nautilus_gradient_set_left_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("", ""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a", ""), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a", "b"), "b-a:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a-c:v", "b"), "b-c:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a-c:v", "c"), "c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a:-b:v", "d"), "d-b:h");
+
+	/* nautilus_gradient_set_top_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("", ""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a", ""), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a", "b"), "b-a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a-c:v", "b"), "b-c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a-c:v", "c"), "c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a:-b:h", "d"), "d-b");
+
+	/* nautilus_gradient_set_right_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("", ""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a", ""), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a", "b"), "a-b:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a-c:v", "b"), "a-b:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a-c:v", "c"), "a-c:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a:-b:v", "d"), "a:-d:h");
+
+	/* nautilus_gradient_set_bottom_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("", ""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a", ""), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a", "b"), "a-b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a-c:v", "b"), "a-b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a-c:v", "c"), "a-c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a:-b:h", "d"), "a:-d");
 }
 
 #endif /* ! NAUTILUS_OMIT_SELF_CHECK */
diff --git a/libnautilus-extensions/gdk-extensions.h b/libnautilus-extensions/gdk-extensions.h
index 57294ec43..8ecadf853 100644
--- a/libnautilus-extensions/gdk-extensions.h
+++ b/libnautilus-extensions/gdk-extensions.h
@@ -27,23 +27,49 @@
 
 #include <gdk/gdk.h>
 
-void nautilus_fill_rectangle               (GdkDrawable        *drawable,
-					    GdkGC              *gc,
-					    const GdkRectangle *rectangle);
-void nautilus_fill_rectangle_with_color    (GdkDrawable        *drawable,
-					    GdkGC              *gc,
-					    const GdkRectangle *rectangle,
-					    const GdkColor     *color);
-void nautilus_fill_rectangle_with_gradient (GdkDrawable        *drawable,
-					    GdkGC              *gc,
-					    GdkColormap        *colormap,
-					    const GdkRectangle *rectangle,
-					    const GdkColor     *start_color,
-					    const GdkColor     *end_color,
-					    gboolean            horizontal_gradient);
-void nautilus_interpolate_color            (gdouble             ratio,
-					    const GdkColor     *start_color,
-					    const GdkColor     *end_color,
-					    GdkColor           *interpolated_color);
+/* A gradient spec. is a string that contains a specifier for either a
+   color or a gradient. If the string has a "-" in it, then it's a gradient.
+   The gradient is vertical by default and the spec. can end with ":v" to indicate that.
+   If the gradient ends with ":h", the gradient is horizontal.
+*/
+char *   nautilus_gradient_new                   (const char *start_color,
+						  const char *end_color,
+						  gboolean    is_horizontal);
+
+gboolean nautilus_gradient_is_gradient           (const char *gradient_spec);
+char *   nautilus_gradient_get_start_color_spec  (const char *gradient_spec);
+char *   nautilus_gradient_get_end_color_spec    (const char *gradient_spec);
+gboolean nautilus_gradient_is_horizontal         (const char *gradient_spec);
+
+char *   nautilus_gradient_set_left_color_spec   (const char *gradient_spec,
+						  const char *left_color);
+char *   nautilus_gradient_set_top_color_spec    (const char *gradient_spec,
+						  const char *top_color);
+char *   nautilus_gradient_set_right_color_spec  (const char *gradient_spec,
+						  const char *right_color);
+char *   nautilus_gradient_set_bottom_color_spec (const char *gradient_spec,
+						  const char *bottom_color);
+
+/* Fill routines that take GdkRectangle parameters instead of four coordinates. */
+void     nautilus_fill_rectangle                (GdkDrawable        *drawable,
+						 GdkGC              *gc,
+						 const GdkRectangle *rectangle);
+void     nautilus_fill_rectangle_with_color     (GdkDrawable        *drawable,
+						 GdkGC              *gc,
+						 const GdkRectangle *rectangle,
+						 const GdkColor     *color);
+void     nautilus_fill_rectangle_with_gradient  (GdkDrawable        *drawable,
+						 GdkGC              *gc,
+						 GdkColormap        *colormap,
+						 const GdkRectangle *rectangle,
+						 const GdkColor     *start_color,
+						 const GdkColor     *end_color,
+						 gboolean            horizontal_gradient);
+
+/* A basic operation needed for drawing gradients is interpolating two colors.*/
+void     nautilus_interpolate_color             (gdouble             ratio,
+						 const GdkColor     *start_color,
+						 const GdkColor     *end_color,
+						 GdkColor           *interpolated_color);
 
 #endif /* GDK_EXTENSIONS_H */
diff --git a/src/nautilus-self-checks.h b/libnautilus-extensions/nautilus-lib-self-check-functions.c
index a8c46e68f..3e8d2e21e 100644
--- a/src/nautilus-self-checks.h
+++ b/libnautilus-extensions/nautilus-lib-self-check-functions.c
@@ -1,8 +1,9 @@
 /* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
    
-   nautilus-self-checks.h: The self-check framework.
+   nautilus-lib-self-check-functions.c: Wrapper for all self check functions
+   in Nautilus proper.
  
-   Copyright (C) 1999 Eazel, Inc.
+   Copyright (C) 2000 Eazel, Inc.
   
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
@@ -22,9 +23,17 @@
    Author: Darin Adler <darin@eazel.com>
 */
 
-#ifndef NAUTILUS_SELF_CHECKS_H
-#define NAUTILUS_SELF_CHECKS_H
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
 
-void nautilus_run_all_self_checks(void);
+#if ! defined (NAUTILUS_OMIT_SELF_CHECK)
 
-#endif /* NAUTILUS_SELF_CHECKS_H */
+#include "nautilus-lib-self-check-functions.h"
+
+void nautilus_run_lib_self_checks ()
+{
+	nautilus_self_check_gdk_extensions ();
+}
+
+#endif /* ! NAUTILUS_OMIT_SELF_CHECK */
diff --git a/libnautilus-extensions/nautilus-lib-self-check-functions.h b/libnautilus-extensions/nautilus-lib-self-check-functions.h
new file mode 100644
index 000000000..dc9ada13a
--- /dev/null
+++ b/libnautilus-extensions/nautilus-lib-self-check-functions.h
@@ -0,0 +1,38 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
+
+   nautilus-lib-self-check-functions.h: Wrapper and prototypes for all
+   self-check functions in libnautilus.
+ 
+   Copyright (C) 2000 Eazel, Inc.
+  
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+  
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+  
+   You should have received a copy of the GNU General Public
+   License along with this program; if not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+  
+   Author: Darin Adler <darin@eazel.com>
+*/
+
+#include "nautilus-self-checks.h"
+
+void nautilus_run_lib_self_checks (void);
+
+/* Putting the prototypes for these self-check functions in each
+   header file for the files they are defined in would make compiling
+   the self-check framework take way too long (since one file would
+   have to include everything).
+
+   So we put the prototypes here instead.
+*/
+
+void nautilus_self_check_gdk_extensions (void);
diff --git a/libnautilus-extensions/nautilus-self-checks.c b/libnautilus-extensions/nautilus-self-checks.c
new file mode 100644
index 000000000..a41df1f9d
--- /dev/null
+++ b/libnautilus-extensions/nautilus-self-checks.c
@@ -0,0 +1,120 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
+   
+   nautilus-self-checks.c: The self-check framework.
+ 
+   Copyright (C) 1999 Eazel, Inc.
+  
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+  
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+  
+   You should have received a copy of the GNU General Public
+   License along with this program; if not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+  
+   Author: Darin Adler <darin@eazel.com>
+*/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#if ! defined (NAUTILUS_OMIT_SELF_CHECK)
+
+#include "nautilus-self-checks.h"
+#include <stdio.h>
+
+static gboolean failed;
+
+static const char *current_expression;
+static const char *current_file_name;
+static int current_line_number;
+
+gboolean nautilus_self_checks_failed (void)
+{
+	return failed;
+}
+
+static void
+nautilus_report_check_failure (char *result, char *expected)
+{
+	printf ("FAIL: check failed in %s, line %d\n", current_file_name, current_line_number);
+	printf ("      evaluated: %s\n", current_expression);
+	printf ("       expected: %s\n", expected == NULL ? "NULL" : expected);
+	printf ("            got: %s\n", result == NULL ? "NULL" : result);
+	
+	failed = TRUE;
+
+	g_free (result);
+	g_free (expected);
+}
+
+static char *
+nautilus_strdup_boolean (gboolean boolean)
+{
+	if (boolean == FALSE)
+		return g_strdup ("FALSE");
+	if (boolean == TRUE)
+		return g_strdup ("TRUE");
+	return g_strdup_printf ("gboolean(%d)", boolean);
+}
+
+void
+nautilus_before_check (const char *expression,
+		       const char *file_name,
+		       int line_number)
+{
+	current_expression = expression;
+	current_file_name = file_name;
+	current_line_number = line_number;
+}
+
+static void
+nautilus_after_check ()
+{
+	/* It would be good to check here if there was a memory leak. */
+}
+
+void
+nautilus_check_boolean_result (gboolean result, gboolean expected)
+{
+	if (result != expected)
+		nautilus_report_check_failure (nautilus_strdup_boolean(result),
+					       nautilus_strdup_boolean(expected));
+	nautilus_after_check ();
+}
+
+void
+nautilus_check_integer_result (long result, long expected)
+{
+	if (result != expected)
+		nautilus_report_check_failure (g_strdup_printf("%ld", result),
+					       g_strdup_printf("%ld", expected));
+
+	nautilus_after_check ();
+}
+
+void
+nautilus_check_string_result (char *result, const char *expected)
+{
+	gboolean match;
+	
+	if (expected == NULL)
+		match = result == NULL;
+	else
+		match = result != NULL && strcmp (result, expected) == 0;
+
+	if (!match)
+		nautilus_report_check_failure (result, g_strdup(expected));
+
+	nautilus_after_check ();
+}
+
+#endif /* ! NAUTILUS_OMIT_SELF_CHECK */
diff --git a/libnautilus-extensions/nautilus-self-checks.h b/libnautilus-extensions/nautilus-self-checks.h
new file mode 100644
index 000000000..bfbdd40c0
--- /dev/null
+++ b/libnautilus-extensions/nautilus-self-checks.h
@@ -0,0 +1,54 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
+   
+   nautilus-self-checks.h: The self-check framework.
+ 
+   Copyright (C) 1999 Eazel, Inc.
+  
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+  
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+  
+   You should have received a copy of the GNU General Public
+   License along with this program; if not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+  
+   Author: Darin Adler <darin@eazel.com>
+*/
+
+#ifndef NAUTILUS_SELF_CHECKS_H
+#define NAUTILUS_SELF_CHECKS_H
+
+#include <glib.h>
+
+gboolean nautilus_self_checks_failed   (void);
+void     nautilus_before_check         (const char *expression,
+					const char *file_name,
+					int         line_number);
+void     nautilus_check_boolean_result (gboolean    result,
+					gboolean    expected_value);
+void     nautilus_check_integer_result (long        result,
+					long        expected_value);
+void     nautilus_check_string_result  (char       *result,
+					const char *expected_value);
+
+#define NAUTILUS_CHECK_RESULT(type, expression, expected_value) \
+G_STMT_START { \
+	nautilus_before_check (#expression, __FILE__, __LINE__); \
+	nautilus_check_##type##_result (expression, expected_value); \
+} G_STMT_END
+
+#define NAUTILUS_CHECK_BOOLEAN_RESULT(expression, expected_value) \
+	NAUTILUS_CHECK_RESULT(boolean, expression, expected_value)
+#define NAUTILUS_CHECK_INTEGER_RESULT(expression, expected_value) \
+	NAUTILUS_CHECK_RESULT(integer, expression, expected_value)
+#define NAUTILUS_CHECK_STRING_RESULT(expression, expected_value) \
+	NAUTILUS_CHECK_RESULT(string, expression, expected_value)
+
+#endif /* NAUTILUS_SELF_CHECKS_H */
diff --git a/libnautilus-private/Makefile.am b/libnautilus-private/Makefile.am
index 719d7d76d..dc583e7f4 100644
--- a/libnautilus-private/Makefile.am
+++ b/libnautilus-private/Makefile.am
@@ -23,6 +23,8 @@ libnautilusinclude_HEADERS=			\
 	gtkscrollframe.h			\
 	nautilus.h				\
 	nautilus-file-utilities.h		\
+	nautilus-lib-self-check-functions.c	\
+	nautilus-self-checks.c			\
 	ntl-content-view-client.h		\
 	ntl-meta-view-client.h			\
 	ntl-view-client.h
@@ -35,6 +37,8 @@ libnautilus_la_SOURCES=$(nautilus_idl_sources)	\
 	gtkflist.c				\
 	gtkscrollframe.c			\
 	nautilus-file-utilities.c		\
+	nautilus-lib-self-check-functions.c	\
+	nautilus-self-checks.c			\
 	ntl-content-view-client.c		\
 	ntl-meta-view-client.c			\
 	ntl-view-client.c			\
diff --git a/libnautilus-private/gdk-extensions.c b/libnautilus-private/gdk-extensions.c
index 0f3184f3e..8f145b5b6 100644
--- a/libnautilus-private/gdk-extensions.c
+++ b/libnautilus-private/gdk-extensions.c
@@ -28,7 +28,9 @@
 
 #include "gdk-extensions.h"
 
-#include "../src/nautilus-self-check-functions.h"
+#include "nautilus-lib-self-check-functions.h"
+
+#include <string.h>
 
 #define GRADIENT_BAND_SIZE 4
 
@@ -178,30 +180,329 @@ nautilus_interpolate_color (gdouble ratio,
 	interpolated_color->blue = start_color->blue * (1.0 - ratio) + end_color->blue * ratio;
 }
 
+/**
+ * nautilus_gradient_new
+ * @start_color: Color for the top or left.
+ * @end_color: Color for the bottom or right.
+ * @is_horizontal: Direction of the gradient.
+ *
+ * Create a string that combines the start and end colors along
+ * with the direction of the gradient in a standard format.
+ */
+char *
+nautilus_gradient_new (const char *start_color,
+		       const char *end_color,
+		       gboolean is_horizontal)
+{
+	g_return_val_if_fail (start_color != NULL, g_strdup (""));
+	g_return_val_if_fail (end_color != NULL, g_strdup (""));
+	g_return_val_if_fail (is_horizontal == FALSE || is_horizontal == TRUE, g_strdup (""));
+
+	/* Handle the special case where the start and end colors are identical.
+	   Handle the special case where the end color is an empty string.
+	*/
+	if (strcmp(start_color, end_color) == 0 || end_color[0] == '\0')
+		return g_strdup (start_color);
+
+	/* Handle the special case where the start color is an empty string. */
+	if (start_color[0] == '\0')
+		return g_strdup (end_color);
+	
+	/* Handle the general case. */
+	return g_strconcat (start_color, "-", end_color, is_horizontal ? ":h" : NULL, NULL);
+}
+
+/**
+ * nautilus_gradient_is_gradient
+ * @gradient_spec: A gradient spec. string.
+ *
+ * Return true if the spec. specifies a gradient instead of a solid color.
+ */
+gboolean
+nautilus_gradient_is_gradient (const char *gradient_spec)
+{
+	g_return_val_if_fail (gradient_spec != NULL, FALSE);
+
+	return strchr (gradient_spec, '-') != NULL;
+}
+
+static char *
+nautilus_gradient_strip_trailing_direction_if_any (const char *gradient_spec)
+{
+	size_t length;
+
+	g_return_val_if_fail (gradient_spec != NULL, g_strdup (""));
+
+	length = strlen (gradient_spec);
+	if (length >= 2 && gradient_spec[length - 2] == ':'
+	    && (gradient_spec[length - 1] == 'v' || gradient_spec[length - 1] == 'h'))
+		length -= 2;
+
+	return g_strndup (gradient_spec, length);
+}
+
+/**
+ * nautilus_gradient_get_start_color_spec
+ * @gradient_spec: A gradient spec. string.
+ *
+ * Return the start color.
+ * This may be the entire gradient_spec if it's a solid color.
+ */
+char *
+nautilus_gradient_get_start_color_spec (const char *gradient_spec)
+{
+	const char *separator;
+	
+	g_return_val_if_fail (gradient_spec != NULL, g_strdup (""));
+	
+	separator = strchr (gradient_spec, '-');
+	if (separator == NULL)
+		return nautilus_gradient_strip_trailing_direction_if_any (gradient_spec);
+
+	return g_strndup (gradient_spec, separator - gradient_spec);
+}
+
+/**
+ * nautilus_gradient_get_end_color_spec
+ * @gradient_spec: A gradient spec. string.
+ *
+ * Return the end color.
+ * This may be the entire gradient_spec if it's a solid color.
+ */
+char *
+nautilus_gradient_get_end_color_spec (const char *gradient_spec)
+{
+	const char *separator;
+
+	g_return_val_if_fail (gradient_spec != NULL, g_strdup (""));
+
+	separator = strchr (gradient_spec, '-');
+	return nautilus_gradient_strip_trailing_direction_if_any
+		(separator != NULL ? separator + 1 : gradient_spec);
+}
+
+/* Do the work shared by all the set_color_spec functions below. */
+static char *
+nautilus_gradient_set_edge_color (const char *gradient_spec,
+				  const char *edge_color,
+				  gboolean is_horizontal,
+				  gboolean change_end)
+{
+	char *opposite_color;
+	char *result;
+
+	g_return_val_if_fail (gradient_spec != NULL, g_strdup (""));
+	g_return_val_if_fail (edge_color != NULL, g_strdup (gradient_spec));
+
+	/* Get the color from the existing gradient spec. for the opposite
+	   edge. This will parse away all the stuff we don't want from the
+	   old gradient spec.
+	*/
+	opposite_color = change_end
+		? nautilus_gradient_get_start_color_spec (gradient_spec)
+		: nautilus_gradient_get_end_color_spec (gradient_spec);
+
+	/* Create a new gradient spec. The nautilus_gradient_new function handles
+	   some special cases, so we don't have to bother with them here.
+	*/
+	result = nautilus_gradient_new (change_end ? opposite_color : edge_color,
+					change_end ? edge_color : opposite_color,
+					is_horizontal);
+
+	g_free (opposite_color);
+
+	return result;
+}
+
+/**
+ * nautilus_gradient_set_left_color_spec
+ * @gradient_spec: A gradient spec. string.
+ * @left_color: Color spec. to replace left color with.
+ *
+ * Changes the left color to what's passed in.
+ * This creates a horizontal gradient.
+ */
+char *
+nautilus_gradient_set_left_color_spec (const char *gradient_spec,
+				       const char *left_color)
+{
+	return nautilus_gradient_set_edge_color (gradient_spec, left_color, TRUE, FALSE);
+}
+
+/**
+ * nautilus_gradient_set_top_color_spec
+ * @gradient_spec: A gradient spec. string.
+ * @top_color: Color spec. to replace top color with.
+ *
+ * Changes the top color to what's passed in.
+ * This creates a vertical gradient.
+ */
+char *
+nautilus_gradient_set_top_color_spec (const char *gradient_spec,
+				      const char *top_color)
+{
+	return nautilus_gradient_set_edge_color (gradient_spec, top_color, FALSE, FALSE);
+}
+
+/**
+ * nautilus_gradient_set_right_color_spec
+ * @gradient_spec: A gradient spec. string.
+ * @right_color: Color spec. to replace right color with.
+ *
+ * Changes the right color to what's passed in.
+ * This creates a horizontal gradient.
+ */
+char *
+nautilus_gradient_set_right_color_spec (const char *gradient_spec,
+					const char *right_color)
+{
+	return nautilus_gradient_set_edge_color (gradient_spec, right_color, TRUE, TRUE);
+}
+
+/**
+ * nautilus_gradient_set_bottom_color_spec
+ * @gradient_spec: A gradient spec. string.
+ * @bottom_color: Color spec. to replace bottom color with.
+ *
+ * Changes the bottom color to what's passed in.
+ * This creates a vertical gradient.
+ */
+char *
+nautilus_gradient_set_bottom_color_spec (const char *gradient_spec,
+					 const char *bottom_color)
+{
+	return nautilus_gradient_set_edge_color (gradient_spec, bottom_color, FALSE, TRUE);
+}
+
 #if ! defined (NAUTILUS_OMIT_SELF_CHECK)
 
-static void
-self_check_interpolate(gdouble ratio,
-		       gushort r1, gushort g1, gushort b1,
-		       gushort r2, gushort g2, gushort b2,
-		       gushort r3, gushort g3, gushort b3)
+#include <stdio.h>
+
+static GdkColor
+nautilus_self_check_interpolate (gdouble ratio,
+				 gushort r1, gushort g1, gushort b1,
+				 gushort r2, gushort g2, gushort b2)
 {
-	GdkColor start_color = { 0, r1, g1, b1 };
-	GdkColor end_color = { 0, r2, g2, b2 };
+	GdkColor start_color;
+	GdkColor end_color;
 	GdkColor interpolated_color;
-	nautilus_interpolate_color(ratio, &start_color, &end_color, &interpolated_color);
-	g_assert(interpolated_color.red == r3);
-	g_assert(interpolated_color.red == g3);
-	g_assert(interpolated_color.red == b3);
+
+	start_color.red = r1;
+	start_color.green = g1;
+	start_color.blue = b1;
+
+	end_color.red = r2;
+	end_color.green = g2;
+	end_color.blue = b2;
+
+	nautilus_interpolate_color (ratio, &start_color, &end_color, &interpolated_color);
+
+	return interpolated_color;
 }
 
 void
-self_check_gdk_extensions (void)
+nautilus_self_check_gdk_extensions (void)
 {
-	self_check_interpolate(0.0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
-	self_check_interpolate(0.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF, 0, 0, 0);
-	self_check_interpolate(0.5, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF, 0x7FFF, 0x7FFF, 0x7FFF);
-	self_check_interpolate(1.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF);
+	/* nautilus_interpolate_color */
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0, 0, 0).red, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0, 0, 0).green, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0, 0, 0).blue, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).red, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).green, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).blue, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.5, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).red, 0x7FFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.5, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).green, 0x7FFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.5, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).blue, 0x7FFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (1.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).red, 0xFFFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (1.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).green, 0xFFFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (1.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).blue, 0xFFFF);
+
+	/* nautilus_fill_rectangle */
+	/* Make a GdkImage and fill it, maybe? */
+
+	/* nautilus_fill_rectangle_with_color */
+
+	/* nautilus_fill_rectangle_with_gradient */
+
+	/* nautilus_gradient_new */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("", "", FALSE), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("a", "b", FALSE), "a-b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("a", "b", TRUE), "a-b:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("a", "a", FALSE), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("a", "a", TRUE), "a");
+
+	/* nautilus_gradient_is_gradient */
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient (""), FALSE);
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient ("-"), TRUE);
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient ("a"), FALSE);
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient ("a-b"), TRUE);
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient ("a-b:h"), TRUE);
+
+	/* nautilus_gradient_get_start_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec (""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("-"), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a-b"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a-"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("-b"), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:h"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:v"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:c"), "a:c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:-b"), "a:");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:-b:v"), "a:");
+
+	/* nautilus_gradient_get_end_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec (""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("-"), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a-b"), "b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a-"), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("-b"), "b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:h"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:v"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:c"), "a:c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:-b"), "b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:-b:v"), "b");
+
+	/* nautilus_gradient_set_left_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("", ""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a", ""), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a", "b"), "b-a:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a-c:v", "b"), "b-c:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a-c:v", "c"), "c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a:-b:v", "d"), "d-b:h");
+
+	/* nautilus_gradient_set_top_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("", ""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a", ""), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a", "b"), "b-a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a-c:v", "b"), "b-c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a-c:v", "c"), "c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a:-b:h", "d"), "d-b");
+
+	/* nautilus_gradient_set_right_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("", ""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a", ""), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a", "b"), "a-b:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a-c:v", "b"), "a-b:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a-c:v", "c"), "a-c:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a:-b:v", "d"), "a:-d:h");
+
+	/* nautilus_gradient_set_bottom_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("", ""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a", ""), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a", "b"), "a-b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a-c:v", "b"), "a-b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a-c:v", "c"), "a-c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a:-b:h", "d"), "a:-d");
 }
 
 #endif /* ! NAUTILUS_OMIT_SELF_CHECK */
diff --git a/libnautilus-private/gdk-extensions.h b/libnautilus-private/gdk-extensions.h
index 57294ec43..8ecadf853 100644
--- a/libnautilus-private/gdk-extensions.h
+++ b/libnautilus-private/gdk-extensions.h
@@ -27,23 +27,49 @@
 
 #include <gdk/gdk.h>
 
-void nautilus_fill_rectangle               (GdkDrawable        *drawable,
-					    GdkGC              *gc,
-					    const GdkRectangle *rectangle);
-void nautilus_fill_rectangle_with_color    (GdkDrawable        *drawable,
-					    GdkGC              *gc,
-					    const GdkRectangle *rectangle,
-					    const GdkColor     *color);
-void nautilus_fill_rectangle_with_gradient (GdkDrawable        *drawable,
-					    GdkGC              *gc,
-					    GdkColormap        *colormap,
-					    const GdkRectangle *rectangle,
-					    const GdkColor     *start_color,
-					    const GdkColor     *end_color,
-					    gboolean            horizontal_gradient);
-void nautilus_interpolate_color            (gdouble             ratio,
-					    const GdkColor     *start_color,
-					    const GdkColor     *end_color,
-					    GdkColor           *interpolated_color);
+/* A gradient spec. is a string that contains a specifier for either a
+   color or a gradient. If the string has a "-" in it, then it's a gradient.
+   The gradient is vertical by default and the spec. can end with ":v" to indicate that.
+   If the gradient ends with ":h", the gradient is horizontal.
+*/
+char *   nautilus_gradient_new                   (const char *start_color,
+						  const char *end_color,
+						  gboolean    is_horizontal);
+
+gboolean nautilus_gradient_is_gradient           (const char *gradient_spec);
+char *   nautilus_gradient_get_start_color_spec  (const char *gradient_spec);
+char *   nautilus_gradient_get_end_color_spec    (const char *gradient_spec);
+gboolean nautilus_gradient_is_horizontal         (const char *gradient_spec);
+
+char *   nautilus_gradient_set_left_color_spec   (const char *gradient_spec,
+						  const char *left_color);
+char *   nautilus_gradient_set_top_color_spec    (const char *gradient_spec,
+						  const char *top_color);
+char *   nautilus_gradient_set_right_color_spec  (const char *gradient_spec,
+						  const char *right_color);
+char *   nautilus_gradient_set_bottom_color_spec (const char *gradient_spec,
+						  const char *bottom_color);
+
+/* Fill routines that take GdkRectangle parameters instead of four coordinates. */
+void     nautilus_fill_rectangle                (GdkDrawable        *drawable,
+						 GdkGC              *gc,
+						 const GdkRectangle *rectangle);
+void     nautilus_fill_rectangle_with_color     (GdkDrawable        *drawable,
+						 GdkGC              *gc,
+						 const GdkRectangle *rectangle,
+						 const GdkColor     *color);
+void     nautilus_fill_rectangle_with_gradient  (GdkDrawable        *drawable,
+						 GdkGC              *gc,
+						 GdkColormap        *colormap,
+						 const GdkRectangle *rectangle,
+						 const GdkColor     *start_color,
+						 const GdkColor     *end_color,
+						 gboolean            horizontal_gradient);
+
+/* A basic operation needed for drawing gradients is interpolating two colors.*/
+void     nautilus_interpolate_color             (gdouble             ratio,
+						 const GdkColor     *start_color,
+						 const GdkColor     *end_color,
+						 GdkColor           *interpolated_color);
 
 #endif /* GDK_EXTENSIONS_H */
diff --git a/libnautilus-private/nautilus-lib-self-check-functions.c b/libnautilus-private/nautilus-lib-self-check-functions.c
new file mode 100644
index 000000000..3e8d2e21e
--- /dev/null
+++ b/libnautilus-private/nautilus-lib-self-check-functions.c
@@ -0,0 +1,39 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
+   
+   nautilus-lib-self-check-functions.c: Wrapper for all self check functions
+   in Nautilus proper.
+ 
+   Copyright (C) 2000 Eazel, Inc.
+  
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+  
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+  
+   You should have received a copy of the GNU General Public
+   License along with this program; if not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+  
+   Author: Darin Adler <darin@eazel.com>
+*/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#if ! defined (NAUTILUS_OMIT_SELF_CHECK)
+
+#include "nautilus-lib-self-check-functions.h"
+
+void nautilus_run_lib_self_checks ()
+{
+	nautilus_self_check_gdk_extensions ();
+}
+
+#endif /* ! NAUTILUS_OMIT_SELF_CHECK */
diff --git a/libnautilus-private/nautilus-lib-self-check-functions.h b/libnautilus-private/nautilus-lib-self-check-functions.h
new file mode 100644
index 000000000..dc9ada13a
--- /dev/null
+++ b/libnautilus-private/nautilus-lib-self-check-functions.h
@@ -0,0 +1,38 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
+
+   nautilus-lib-self-check-functions.h: Wrapper and prototypes for all
+   self-check functions in libnautilus.
+ 
+   Copyright (C) 2000 Eazel, Inc.
+  
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+  
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+  
+   You should have received a copy of the GNU General Public
+   License along with this program; if not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+  
+   Author: Darin Adler <darin@eazel.com>
+*/
+
+#include "nautilus-self-checks.h"
+
+void nautilus_run_lib_self_checks (void);
+
+/* Putting the prototypes for these self-check functions in each
+   header file for the files they are defined in would make compiling
+   the self-check framework take way too long (since one file would
+   have to include everything).
+
+   So we put the prototypes here instead.
+*/
+
+void nautilus_self_check_gdk_extensions (void);
diff --git a/libnautilus-private/nautilus-self-checks.c b/libnautilus-private/nautilus-self-checks.c
new file mode 100644
index 000000000..a41df1f9d
--- /dev/null
+++ b/libnautilus-private/nautilus-self-checks.c
@@ -0,0 +1,120 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
+   
+   nautilus-self-checks.c: The self-check framework.
+ 
+   Copyright (C) 1999 Eazel, Inc.
+  
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+  
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+  
+   You should have received a copy of the GNU General Public
+   License along with this program; if not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+  
+   Author: Darin Adler <darin@eazel.com>
+*/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#if ! defined (NAUTILUS_OMIT_SELF_CHECK)
+
+#include "nautilus-self-checks.h"
+#include <stdio.h>
+
+static gboolean failed;
+
+static const char *current_expression;
+static const char *current_file_name;
+static int current_line_number;
+
+gboolean nautilus_self_checks_failed (void)
+{
+	return failed;
+}
+
+static void
+nautilus_report_check_failure (char *result, char *expected)
+{
+	printf ("FAIL: check failed in %s, line %d\n", current_file_name, current_line_number);
+	printf ("      evaluated: %s\n", current_expression);
+	printf ("       expected: %s\n", expected == NULL ? "NULL" : expected);
+	printf ("            got: %s\n", result == NULL ? "NULL" : result);
+	
+	failed = TRUE;
+
+	g_free (result);
+	g_free (expected);
+}
+
+static char *
+nautilus_strdup_boolean (gboolean boolean)
+{
+	if (boolean == FALSE)
+		return g_strdup ("FALSE");
+	if (boolean == TRUE)
+		return g_strdup ("TRUE");
+	return g_strdup_printf ("gboolean(%d)", boolean);
+}
+
+void
+nautilus_before_check (const char *expression,
+		       const char *file_name,
+		       int line_number)
+{
+	current_expression = expression;
+	current_file_name = file_name;
+	current_line_number = line_number;
+}
+
+static void
+nautilus_after_check ()
+{
+	/* It would be good to check here if there was a memory leak. */
+}
+
+void
+nautilus_check_boolean_result (gboolean result, gboolean expected)
+{
+	if (result != expected)
+		nautilus_report_check_failure (nautilus_strdup_boolean(result),
+					       nautilus_strdup_boolean(expected));
+	nautilus_after_check ();
+}
+
+void
+nautilus_check_integer_result (long result, long expected)
+{
+	if (result != expected)
+		nautilus_report_check_failure (g_strdup_printf("%ld", result),
+					       g_strdup_printf("%ld", expected));
+
+	nautilus_after_check ();
+}
+
+void
+nautilus_check_string_result (char *result, const char *expected)
+{
+	gboolean match;
+	
+	if (expected == NULL)
+		match = result == NULL;
+	else
+		match = result != NULL && strcmp (result, expected) == 0;
+
+	if (!match)
+		nautilus_report_check_failure (result, g_strdup(expected));
+
+	nautilus_after_check ();
+}
+
+#endif /* ! NAUTILUS_OMIT_SELF_CHECK */
diff --git a/libnautilus-private/nautilus-self-checks.h b/libnautilus-private/nautilus-self-checks.h
new file mode 100644
index 000000000..bfbdd40c0
--- /dev/null
+++ b/libnautilus-private/nautilus-self-checks.h
@@ -0,0 +1,54 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
+   
+   nautilus-self-checks.h: The self-check framework.
+ 
+   Copyright (C) 1999 Eazel, Inc.
+  
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+  
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+  
+   You should have received a copy of the GNU General Public
+   License along with this program; if not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+  
+   Author: Darin Adler <darin@eazel.com>
+*/
+
+#ifndef NAUTILUS_SELF_CHECKS_H
+#define NAUTILUS_SELF_CHECKS_H
+
+#include <glib.h>
+
+gboolean nautilus_self_checks_failed   (void);
+void     nautilus_before_check         (const char *expression,
+					const char *file_name,
+					int         line_number);
+void     nautilus_check_boolean_result (gboolean    result,
+					gboolean    expected_value);
+void     nautilus_check_integer_result (long        result,
+					long        expected_value);
+void     nautilus_check_string_result  (char       *result,
+					const char *expected_value);
+
+#define NAUTILUS_CHECK_RESULT(type, expression, expected_value) \
+G_STMT_START { \
+	nautilus_before_check (#expression, __FILE__, __LINE__); \
+	nautilus_check_##type##_result (expression, expected_value); \
+} G_STMT_END
+
+#define NAUTILUS_CHECK_BOOLEAN_RESULT(expression, expected_value) \
+	NAUTILUS_CHECK_RESULT(boolean, expression, expected_value)
+#define NAUTILUS_CHECK_INTEGER_RESULT(expression, expected_value) \
+	NAUTILUS_CHECK_RESULT(integer, expression, expected_value)
+#define NAUTILUS_CHECK_STRING_RESULT(expression, expected_value) \
+	NAUTILUS_CHECK_RESULT(string, expression, expected_value)
+
+#endif /* NAUTILUS_SELF_CHECKS_H */
diff --git a/libnautilus/Makefile.am b/libnautilus/Makefile.am
index 719d7d76d..dc583e7f4 100644
--- a/libnautilus/Makefile.am
+++ b/libnautilus/Makefile.am
@@ -23,6 +23,8 @@ libnautilusinclude_HEADERS=			\
 	gtkscrollframe.h			\
 	nautilus.h				\
 	nautilus-file-utilities.h		\
+	nautilus-lib-self-check-functions.c	\
+	nautilus-self-checks.c			\
 	ntl-content-view-client.h		\
 	ntl-meta-view-client.h			\
 	ntl-view-client.h
@@ -35,6 +37,8 @@ libnautilus_la_SOURCES=$(nautilus_idl_sources)	\
 	gtkflist.c				\
 	gtkscrollframe.c			\
 	nautilus-file-utilities.c		\
+	nautilus-lib-self-check-functions.c	\
+	nautilus-self-checks.c			\
 	ntl-content-view-client.c		\
 	ntl-meta-view-client.c			\
 	ntl-view-client.c			\
diff --git a/libnautilus/gdk-extensions.c b/libnautilus/gdk-extensions.c
index 0f3184f3e..8f145b5b6 100644
--- a/libnautilus/gdk-extensions.c
+++ b/libnautilus/gdk-extensions.c
@@ -28,7 +28,9 @@
 
 #include "gdk-extensions.h"
 
-#include "../src/nautilus-self-check-functions.h"
+#include "nautilus-lib-self-check-functions.h"
+
+#include <string.h>
 
 #define GRADIENT_BAND_SIZE 4
 
@@ -178,30 +180,329 @@ nautilus_interpolate_color (gdouble ratio,
 	interpolated_color->blue = start_color->blue * (1.0 - ratio) + end_color->blue * ratio;
 }
 
+/**
+ * nautilus_gradient_new
+ * @start_color: Color for the top or left.
+ * @end_color: Color for the bottom or right.
+ * @is_horizontal: Direction of the gradient.
+ *
+ * Create a string that combines the start and end colors along
+ * with the direction of the gradient in a standard format.
+ */
+char *
+nautilus_gradient_new (const char *start_color,
+		       const char *end_color,
+		       gboolean is_horizontal)
+{
+	g_return_val_if_fail (start_color != NULL, g_strdup (""));
+	g_return_val_if_fail (end_color != NULL, g_strdup (""));
+	g_return_val_if_fail (is_horizontal == FALSE || is_horizontal == TRUE, g_strdup (""));
+
+	/* Handle the special case where the start and end colors are identical.
+	   Handle the special case where the end color is an empty string.
+	*/
+	if (strcmp(start_color, end_color) == 0 || end_color[0] == '\0')
+		return g_strdup (start_color);
+
+	/* Handle the special case where the start color is an empty string. */
+	if (start_color[0] == '\0')
+		return g_strdup (end_color);
+	
+	/* Handle the general case. */
+	return g_strconcat (start_color, "-", end_color, is_horizontal ? ":h" : NULL, NULL);
+}
+
+/**
+ * nautilus_gradient_is_gradient
+ * @gradient_spec: A gradient spec. string.
+ *
+ * Return true if the spec. specifies a gradient instead of a solid color.
+ */
+gboolean
+nautilus_gradient_is_gradient (const char *gradient_spec)
+{
+	g_return_val_if_fail (gradient_spec != NULL, FALSE);
+
+	return strchr (gradient_spec, '-') != NULL;
+}
+
+static char *
+nautilus_gradient_strip_trailing_direction_if_any (const char *gradient_spec)
+{
+	size_t length;
+
+	g_return_val_if_fail (gradient_spec != NULL, g_strdup (""));
+
+	length = strlen (gradient_spec);
+	if (length >= 2 && gradient_spec[length - 2] == ':'
+	    && (gradient_spec[length - 1] == 'v' || gradient_spec[length - 1] == 'h'))
+		length -= 2;
+
+	return g_strndup (gradient_spec, length);
+}
+
+/**
+ * nautilus_gradient_get_start_color_spec
+ * @gradient_spec: A gradient spec. string.
+ *
+ * Return the start color.
+ * This may be the entire gradient_spec if it's a solid color.
+ */
+char *
+nautilus_gradient_get_start_color_spec (const char *gradient_spec)
+{
+	const char *separator;
+	
+	g_return_val_if_fail (gradient_spec != NULL, g_strdup (""));
+	
+	separator = strchr (gradient_spec, '-');
+	if (separator == NULL)
+		return nautilus_gradient_strip_trailing_direction_if_any (gradient_spec);
+
+	return g_strndup (gradient_spec, separator - gradient_spec);
+}
+
+/**
+ * nautilus_gradient_get_end_color_spec
+ * @gradient_spec: A gradient spec. string.
+ *
+ * Return the end color.
+ * This may be the entire gradient_spec if it's a solid color.
+ */
+char *
+nautilus_gradient_get_end_color_spec (const char *gradient_spec)
+{
+	const char *separator;
+
+	g_return_val_if_fail (gradient_spec != NULL, g_strdup (""));
+
+	separator = strchr (gradient_spec, '-');
+	return nautilus_gradient_strip_trailing_direction_if_any
+		(separator != NULL ? separator + 1 : gradient_spec);
+}
+
+/* Do the work shared by all the set_color_spec functions below. */
+static char *
+nautilus_gradient_set_edge_color (const char *gradient_spec,
+				  const char *edge_color,
+				  gboolean is_horizontal,
+				  gboolean change_end)
+{
+	char *opposite_color;
+	char *result;
+
+	g_return_val_if_fail (gradient_spec != NULL, g_strdup (""));
+	g_return_val_if_fail (edge_color != NULL, g_strdup (gradient_spec));
+
+	/* Get the color from the existing gradient spec. for the opposite
+	   edge. This will parse away all the stuff we don't want from the
+	   old gradient spec.
+	*/
+	opposite_color = change_end
+		? nautilus_gradient_get_start_color_spec (gradient_spec)
+		: nautilus_gradient_get_end_color_spec (gradient_spec);
+
+	/* Create a new gradient spec. The nautilus_gradient_new function handles
+	   some special cases, so we don't have to bother with them here.
+	*/
+	result = nautilus_gradient_new (change_end ? opposite_color : edge_color,
+					change_end ? edge_color : opposite_color,
+					is_horizontal);
+
+	g_free (opposite_color);
+
+	return result;
+}
+
+/**
+ * nautilus_gradient_set_left_color_spec
+ * @gradient_spec: A gradient spec. string.
+ * @left_color: Color spec. to replace left color with.
+ *
+ * Changes the left color to what's passed in.
+ * This creates a horizontal gradient.
+ */
+char *
+nautilus_gradient_set_left_color_spec (const char *gradient_spec,
+				       const char *left_color)
+{
+	return nautilus_gradient_set_edge_color (gradient_spec, left_color, TRUE, FALSE);
+}
+
+/**
+ * nautilus_gradient_set_top_color_spec
+ * @gradient_spec: A gradient spec. string.
+ * @top_color: Color spec. to replace top color with.
+ *
+ * Changes the top color to what's passed in.
+ * This creates a vertical gradient.
+ */
+char *
+nautilus_gradient_set_top_color_spec (const char *gradient_spec,
+				      const char *top_color)
+{
+	return nautilus_gradient_set_edge_color (gradient_spec, top_color, FALSE, FALSE);
+}
+
+/**
+ * nautilus_gradient_set_right_color_spec
+ * @gradient_spec: A gradient spec. string.
+ * @right_color: Color spec. to replace right color with.
+ *
+ * Changes the right color to what's passed in.
+ * This creates a horizontal gradient.
+ */
+char *
+nautilus_gradient_set_right_color_spec (const char *gradient_spec,
+					const char *right_color)
+{
+	return nautilus_gradient_set_edge_color (gradient_spec, right_color, TRUE, TRUE);
+}
+
+/**
+ * nautilus_gradient_set_bottom_color_spec
+ * @gradient_spec: A gradient spec. string.
+ * @bottom_color: Color spec. to replace bottom color with.
+ *
+ * Changes the bottom color to what's passed in.
+ * This creates a vertical gradient.
+ */
+char *
+nautilus_gradient_set_bottom_color_spec (const char *gradient_spec,
+					 const char *bottom_color)
+{
+	return nautilus_gradient_set_edge_color (gradient_spec, bottom_color, FALSE, TRUE);
+}
+
 #if ! defined (NAUTILUS_OMIT_SELF_CHECK)
 
-static void
-self_check_interpolate(gdouble ratio,
-		       gushort r1, gushort g1, gushort b1,
-		       gushort r2, gushort g2, gushort b2,
-		       gushort r3, gushort g3, gushort b3)
+#include <stdio.h>
+
+static GdkColor
+nautilus_self_check_interpolate (gdouble ratio,
+				 gushort r1, gushort g1, gushort b1,
+				 gushort r2, gushort g2, gushort b2)
 {
-	GdkColor start_color = { 0, r1, g1, b1 };
-	GdkColor end_color = { 0, r2, g2, b2 };
+	GdkColor start_color;
+	GdkColor end_color;
 	GdkColor interpolated_color;
-	nautilus_interpolate_color(ratio, &start_color, &end_color, &interpolated_color);
-	g_assert(interpolated_color.red == r3);
-	g_assert(interpolated_color.red == g3);
-	g_assert(interpolated_color.red == b3);
+
+	start_color.red = r1;
+	start_color.green = g1;
+	start_color.blue = b1;
+
+	end_color.red = r2;
+	end_color.green = g2;
+	end_color.blue = b2;
+
+	nautilus_interpolate_color (ratio, &start_color, &end_color, &interpolated_color);
+
+	return interpolated_color;
 }
 
 void
-self_check_gdk_extensions (void)
+nautilus_self_check_gdk_extensions (void)
 {
-	self_check_interpolate(0.0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
-	self_check_interpolate(0.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF, 0, 0, 0);
-	self_check_interpolate(0.5, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF, 0x7FFF, 0x7FFF, 0x7FFF);
-	self_check_interpolate(1.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF);
+	/* nautilus_interpolate_color */
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0, 0, 0).red, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0, 0, 0).green, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0, 0, 0).blue, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).red, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).green, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).blue, 0);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.5, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).red, 0x7FFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.5, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).green, 0x7FFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (0.5, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).blue, 0x7FFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (1.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).red, 0xFFFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (1.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).green, 0xFFFF);
+	NAUTILUS_CHECK_INTEGER_RESULT (nautilus_self_check_interpolate (1.0, 0, 0, 0, 0xFFFF, 0xFFFF, 0xFFFF).blue, 0xFFFF);
+
+	/* nautilus_fill_rectangle */
+	/* Make a GdkImage and fill it, maybe? */
+
+	/* nautilus_fill_rectangle_with_color */
+
+	/* nautilus_fill_rectangle_with_gradient */
+
+	/* nautilus_gradient_new */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("", "", FALSE), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("a", "b", FALSE), "a-b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("a", "b", TRUE), "a-b:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("a", "a", FALSE), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_new ("a", "a", TRUE), "a");
+
+	/* nautilus_gradient_is_gradient */
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient (""), FALSE);
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient ("-"), TRUE);
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient ("a"), FALSE);
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient ("a-b"), TRUE);
+	NAUTILUS_CHECK_BOOLEAN_RESULT (nautilus_gradient_is_gradient ("a-b:h"), TRUE);
+
+	/* nautilus_gradient_get_start_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec (""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("-"), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a-b"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a-"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("-b"), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:h"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:v"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:c"), "a:c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:-b"), "a:");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_start_color_spec ("a:-b:v"), "a:");
+
+	/* nautilus_gradient_get_end_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec (""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("-"), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a-b"), "b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a-"), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("-b"), "b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:h"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:v"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:c"), "a:c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:-b"), "b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_get_end_color_spec ("a:-b:v"), "b");
+
+	/* nautilus_gradient_set_left_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("", ""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a", ""), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a", "b"), "b-a:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a-c:v", "b"), "b-c:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a-c:v", "c"), "c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_left_color_spec ("a:-b:v", "d"), "d-b:h");
+
+	/* nautilus_gradient_set_top_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("", ""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a", ""), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a", "b"), "b-a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a-c:v", "b"), "b-c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a-c:v", "c"), "c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_top_color_spec ("a:-b:h", "d"), "d-b");
+
+	/* nautilus_gradient_set_right_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("", ""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a", ""), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a", "b"), "a-b:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a-c:v", "b"), "a-b:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a-c:v", "c"), "a-c:h");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_right_color_spec ("a:-b:v", "d"), "a:-d:h");
+
+	/* nautilus_gradient_set_bottom_color_spec */
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("", ""), "");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a", ""), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a", "a"), "a");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a", "b"), "a-b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a-c:v", "b"), "a-b");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a-c:v", "c"), "a-c");
+	NAUTILUS_CHECK_STRING_RESULT (nautilus_gradient_set_bottom_color_spec ("a:-b:h", "d"), "a:-d");
 }
 
 #endif /* ! NAUTILUS_OMIT_SELF_CHECK */
diff --git a/libnautilus/gdk-extensions.h b/libnautilus/gdk-extensions.h
index 57294ec43..8ecadf853 100644
--- a/libnautilus/gdk-extensions.h
+++ b/libnautilus/gdk-extensions.h
@@ -27,23 +27,49 @@
 
 #include <gdk/gdk.h>
 
-void nautilus_fill_rectangle               (GdkDrawable        *drawable,
-					    GdkGC              *gc,
-					    const GdkRectangle *rectangle);
-void nautilus_fill_rectangle_with_color    (GdkDrawable        *drawable,
-					    GdkGC              *gc,
-					    const GdkRectangle *rectangle,
-					    const GdkColor     *color);
-void nautilus_fill_rectangle_with_gradient (GdkDrawable        *drawable,
-					    GdkGC              *gc,
-					    GdkColormap        *colormap,
-					    const GdkRectangle *rectangle,
-					    const GdkColor     *start_color,
-					    const GdkColor     *end_color,
-					    gboolean            horizontal_gradient);
-void nautilus_interpolate_color            (gdouble             ratio,
-					    const GdkColor     *start_color,
-					    const GdkColor     *end_color,
-					    GdkColor           *interpolated_color);
+/* A gradient spec. is a string that contains a specifier for either a
+   color or a gradient. If the string has a "-" in it, then it's a gradient.
+   The gradient is vertical by default and the spec. can end with ":v" to indicate that.
+   If the gradient ends with ":h", the gradient is horizontal.
+*/
+char *   nautilus_gradient_new                   (const char *start_color,
+						  const char *end_color,
+						  gboolean    is_horizontal);
+
+gboolean nautilus_gradient_is_gradient           (const char *gradient_spec);
+char *   nautilus_gradient_get_start_color_spec  (const char *gradient_spec);
+char *   nautilus_gradient_get_end_color_spec    (const char *gradient_spec);
+gboolean nautilus_gradient_is_horizontal         (const char *gradient_spec);
+
+char *   nautilus_gradient_set_left_color_spec   (const char *gradient_spec,
+						  const char *left_color);
+char *   nautilus_gradient_set_top_color_spec    (const char *gradient_spec,
+						  const char *top_color);
+char *   nautilus_gradient_set_right_color_spec  (const char *gradient_spec,
+						  const char *right_color);
+char *   nautilus_gradient_set_bottom_color_spec (const char *gradient_spec,
+						  const char *bottom_color);
+
+/* Fill routines that take GdkRectangle parameters instead of four coordinates. */
+void     nautilus_fill_rectangle                (GdkDrawable        *drawable,
+						 GdkGC              *gc,
+						 const GdkRectangle *rectangle);
+void     nautilus_fill_rectangle_with_color     (GdkDrawable        *drawable,
+						 GdkGC              *gc,
+						 const GdkRectangle *rectangle,
+						 const GdkColor     *color);
+void     nautilus_fill_rectangle_with_gradient  (GdkDrawable        *drawable,
+						 GdkGC              *gc,
+						 GdkColormap        *colormap,
+						 const GdkRectangle *rectangle,
+						 const GdkColor     *start_color,
+						 const GdkColor     *end_color,
+						 gboolean            horizontal_gradient);
+
+/* A basic operation needed for drawing gradients is interpolating two colors.*/
+void     nautilus_interpolate_color             (gdouble             ratio,
+						 const GdkColor     *start_color,
+						 const GdkColor     *end_color,
+						 GdkColor           *interpolated_color);
 
 #endif /* GDK_EXTENSIONS_H */
diff --git a/libnautilus/nautilus-lib-self-check-functions.c b/libnautilus/nautilus-lib-self-check-functions.c
new file mode 100644
index 000000000..3e8d2e21e
--- /dev/null
+++ b/libnautilus/nautilus-lib-self-check-functions.c
@@ -0,0 +1,39 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
+   
+   nautilus-lib-self-check-functions.c: Wrapper for all self check functions
+   in Nautilus proper.
+ 
+   Copyright (C) 2000 Eazel, Inc.
+  
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+  
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+  
+   You should have received a copy of the GNU General Public
+   License along with this program; if not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+  
+   Author: Darin Adler <darin@eazel.com>
+*/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#if ! defined (NAUTILUS_OMIT_SELF_CHECK)
+
+#include "nautilus-lib-self-check-functions.h"
+
+void nautilus_run_lib_self_checks ()
+{
+	nautilus_self_check_gdk_extensions ();
+}
+
+#endif /* ! NAUTILUS_OMIT_SELF_CHECK */
diff --git a/libnautilus/nautilus-lib-self-check-functions.h b/libnautilus/nautilus-lib-self-check-functions.h
new file mode 100644
index 000000000..dc9ada13a
--- /dev/null
+++ b/libnautilus/nautilus-lib-self-check-functions.h
@@ -0,0 +1,38 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
+
+   nautilus-lib-self-check-functions.h: Wrapper and prototypes for all
+   self-check functions in libnautilus.
+ 
+   Copyright (C) 2000 Eazel, Inc.
+  
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+  
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+  
+   You should have received a copy of the GNU General Public
+   License along with this program; if not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+  
+   Author: Darin Adler <darin@eazel.com>
+*/
+
+#include "nautilus-self-checks.h"
+
+void nautilus_run_lib_self_checks (void);
+
+/* Putting the prototypes for these self-check functions in each
+   header file for the files they are defined in would make compiling
+   the self-check framework take way too long (since one file would
+   have to include everything).
+
+   So we put the prototypes here instead.
+*/
+
+void nautilus_self_check_gdk_extensions (void);
diff --git a/libnautilus/nautilus-self-checks.c b/libnautilus/nautilus-self-checks.c
new file mode 100644
index 000000000..a41df1f9d
--- /dev/null
+++ b/libnautilus/nautilus-self-checks.c
@@ -0,0 +1,120 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
+   
+   nautilus-self-checks.c: The self-check framework.
+ 
+   Copyright (C) 1999 Eazel, Inc.
+  
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+  
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+  
+   You should have received a copy of the GNU General Public
+   License along with this program; if not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+  
+   Author: Darin Adler <darin@eazel.com>
+*/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#if ! defined (NAUTILUS_OMIT_SELF_CHECK)
+
+#include "nautilus-self-checks.h"
+#include <stdio.h>
+
+static gboolean failed;
+
+static const char *current_expression;
+static const char *current_file_name;
+static int current_line_number;
+
+gboolean nautilus_self_checks_failed (void)
+{
+	return failed;
+}
+
+static void
+nautilus_report_check_failure (char *result, char *expected)
+{
+	printf ("FAIL: check failed in %s, line %d\n", current_file_name, current_line_number);
+	printf ("      evaluated: %s\n", current_expression);
+	printf ("       expected: %s\n", expected == NULL ? "NULL" : expected);
+	printf ("            got: %s\n", result == NULL ? "NULL" : result);
+	
+	failed = TRUE;
+
+	g_free (result);
+	g_free (expected);
+}
+
+static char *
+nautilus_strdup_boolean (gboolean boolean)
+{
+	if (boolean == FALSE)
+		return g_strdup ("FALSE");
+	if (boolean == TRUE)
+		return g_strdup ("TRUE");
+	return g_strdup_printf ("gboolean(%d)", boolean);
+}
+
+void
+nautilus_before_check (const char *expression,
+		       const char *file_name,
+		       int line_number)
+{
+	current_expression = expression;
+	current_file_name = file_name;
+	current_line_number = line_number;
+}
+
+static void
+nautilus_after_check ()
+{
+	/* It would be good to check here if there was a memory leak. */
+}
+
+void
+nautilus_check_boolean_result (gboolean result, gboolean expected)
+{
+	if (result != expected)
+		nautilus_report_check_failure (nautilus_strdup_boolean(result),
+					       nautilus_strdup_boolean(expected));
+	nautilus_after_check ();
+}
+
+void
+nautilus_check_integer_result (long result, long expected)
+{
+	if (result != expected)
+		nautilus_report_check_failure (g_strdup_printf("%ld", result),
+					       g_strdup_printf("%ld", expected));
+
+	nautilus_after_check ();
+}
+
+void
+nautilus_check_string_result (char *result, const char *expected)
+{
+	gboolean match;
+	
+	if (expected == NULL)
+		match = result == NULL;
+	else
+		match = result != NULL && strcmp (result, expected) == 0;
+
+	if (!match)
+		nautilus_report_check_failure (result, g_strdup(expected));
+
+	nautilus_after_check ();
+}
+
+#endif /* ! NAUTILUS_OMIT_SELF_CHECK */
diff --git a/libnautilus/nautilus-self-checks.h b/libnautilus/nautilus-self-checks.h
new file mode 100644
index 000000000..bfbdd40c0
--- /dev/null
+++ b/libnautilus/nautilus-self-checks.h
@@ -0,0 +1,54 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
+   
+   nautilus-self-checks.h: The self-check framework.
+ 
+   Copyright (C) 1999 Eazel, Inc.
+  
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+  
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+  
+   You should have received a copy of the GNU General Public
+   License along with this program; if not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+  
+   Author: Darin Adler <darin@eazel.com>
+*/
+
+#ifndef NAUTILUS_SELF_CHECKS_H
+#define NAUTILUS_SELF_CHECKS_H
+
+#include <glib.h>
+
+gboolean nautilus_self_checks_failed   (void);
+void     nautilus_before_check         (const char *expression,
+					const char *file_name,
+					int         line_number);
+void     nautilus_check_boolean_result (gboolean    result,
+					gboolean    expected_value);
+void     nautilus_check_integer_result (long        result,
+					long        expected_value);
+void     nautilus_check_string_result  (char       *result,
+					const char *expected_value);
+
+#define NAUTILUS_CHECK_RESULT(type, expression, expected_value) \
+G_STMT_START { \
+	nautilus_before_check (#expression, __FILE__, __LINE__); \
+	nautilus_check_##type##_result (expression, expected_value); \
+} G_STMT_END
+
+#define NAUTILUS_CHECK_BOOLEAN_RESULT(expression, expected_value) \
+	NAUTILUS_CHECK_RESULT(boolean, expression, expected_value)
+#define NAUTILUS_CHECK_INTEGER_RESULT(expression, expected_value) \
+	NAUTILUS_CHECK_RESULT(integer, expression, expected_value)
+#define NAUTILUS_CHECK_STRING_RESULT(expression, expected_value) \
+	NAUTILUS_CHECK_RESULT(string, expression, expected_value)
+
+#endif /* NAUTILUS_SELF_CHECKS_H */
diff --git a/src/Makefile.am b/src/Makefile.am
index 3c46b917f..996c15cc8 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -20,46 +20,46 @@ LDADD=	file-manager/libntl-file-manager.la \
 	$(XML_LIBS)
 
 nautilus_SOURCES=			\
-	nautilus-bookmark.h		\
+	explorer-location-bar.c         \
+	explorer-location-bar.h		\
 	nautilus-bookmark.c		\
-	nautilus-bookmarklist.h		\
+	nautilus-bookmark.h		\
 	nautilus-bookmarklist.c		\
-	nautilus-bookmarks-menu.h	\
+	nautilus-bookmarklist.h		\
 	nautilus-bookmarks-menu.c	\
-	nautilus-bookmarks-window.h	\
+	nautilus-bookmarks-menu.h	\
 	nautilus-bookmarks-window.c	\
-	nautilus-self-checks.c		\
-	nautilus-self-checks.h		\
-	ntl-app.h			\
+	nautilus-bookmarks-window.h	\
+        nautilus-self-check-functions.c \
+        nautilus-self-check-functions.h \
 	ntl-app.c			\
-	ntl-content-view.h		\
+	ntl-app.h			\
 	ntl-content-view.c		\
+	ntl-content-view.h		\
 	ntl-main.c 			\
-	ntl-meta-view.h			\
 	ntl-meta-view.c			\
-	ntl-miniicon.h			\
+	ntl-meta-view.h			\
 	ntl-miniicon.c			\
-	ntl-prefs.h			\
+	ntl-miniicon.h			\
 	ntl-prefs.c			\
+	ntl-prefs.h			\
 	ntl-types.h			\
-	ntl-uri-map.h			\
 	ntl-uri-map.c			\
-	ntl-view.h			\
-	ntl-view.c			\
+	ntl-uri-map.h			\
 	ntl-view-bonobo-control.c	\
 	ntl-view-bonobo-subdoc.c	\
+	ntl-view.c			\
 	ntl-view-frame-svr.c		\
+	ntl-view.h			\
 	ntl-view-nautilus.c		\
 	ntl-view-private.h		\
-	ntl-window.h			\
 	ntl-window.c			\
+	ntl-window.h			\
 	ntl-window-msgs.c		\
 	ntl-window-msgs.h		\
 	ntl-window-private.h		\
-	ntl-window-state.h		\
 	ntl-window-state.c		\
-	explorer-location-bar.h		\
-	explorer-location-bar.c
+	ntl-window-state.h
 
 goaddir=$(sysconfdir)/CORBA/servers
 goad_DATA=nautilus.goad
diff --git a/src/file-manager/fm-directory.c b/src/file-manager/fm-directory.c
index de80547bf..cb662338d 100644
--- a/src/file-manager/fm-directory.c
+++ b/src/file-manager/fm-directory.c
@@ -2,7 +2,7 @@
 
    fm-directory.c: GNOME file manager directory model.
  
-   Copyright (C) 1999 Eazel, Inc.
+   Copyright (C) 1999, 2000 Eazel, Inc.
   
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
@@ -30,13 +30,21 @@
 
 #include "fm-directory-protected.h"
 #include "fm-vfs-directory.h"
+#include <gtk/gtksignal.h>
 #include <libnautilus/nautilus-gtk-macros.h>
 #include "../nautilus-self-check-functions.h"
 
 static void fm_directory_destroy (GtkObject *object);
 static void fm_directory_finalize (GtkObject *object);
 
+enum {
+	GET_FILES,
+	LAST_SIGNAL
+};
+
 static GtkObjectClass *parent_class;
+static guint signals[LAST_SIGNAL];
+
 static GHashTable* directory_objects;
 
 static void
@@ -46,6 +54,17 @@ fm_directory_initialize_class (gpointer klass)
 
 	object_class = GTK_OBJECT_CLASS (klass);
 	parent_class = gtk_type_class (GTK_TYPE_OBJECT);
+	
+	signals[GET_FILES] =
+		gtk_signal_new ("get_files",
+				GTK_RUN_FIRST,
+				object_class->type,
+				GTK_SIGNAL_OFFSET (FMDirectoryClass, get_files),
+				gtk_marshal_NONE__POINTER_POINTER,
+				GTK_TYPE_NONE,
+				2, GTK_TYPE_POINTER, GTK_TYPE_POINTER);
+
+	gtk_object_class_add_signals (object_class, signals, LAST_SIGNAL);
 
 	object_class->destroy = fm_directory_destroy;
 	object_class->finalize = fm_directory_finalize;
@@ -95,7 +114,8 @@ NAUTILUS_DEFINE_GET_TYPE_FUNCTION(FMDirectory, fm_directory, GTK_TYPE_OBJECT)
  * Returns a referenced object, not a floating one. Unref when finished.
  * If two windows are viewing the same uri, the directory object is shared.
  */
-FMDirectory *fm_directory_get(const char *uri)
+FMDirectory *
+fm_directory_get(const char *uri)
 {
 	FMDirectory *directory;
 
@@ -128,15 +148,49 @@ FMDirectory *fm_directory_get(const char *uri)
 	return directory;
 }
 
+void
+fm_directory_get_files(FMDirectory *directory,
+		       FMFileListCallback callback,
+		       gpointer callback_data)
+{
+	g_return_if_fail(FM_IS_DIRECTORY(directory));
+	g_return_if_fail(callback);
+
+	gtk_signal_emit(GTK_OBJECT(directory), signals[GET_FILES], callback, callback_data);
+}
+
 /* self check code */
 
 #if !defined (NAUTILUS_OMIT_SELF_CHECK)
 
-void self_check_fm_directory(void)
+static int data_dummy;
+static guint file_count;
+
+static void
+get_files_cb(FMDirectory *directory, FMFileList *files, gpointer data)
+{
+	g_assert(FM_IS_DIRECTORY(directory));
+	g_assert(files);
+	g_assert(data == &data_dummy);
+
+	file_count += g_list_length(files);
+}
+
+void
+nautilus_self_check_fm_directory(void)
 {
 	FMDirectory *directory;
 
 	directory = fm_directory_get("file:///etc");
+
+	g_assert(g_hash_table_size(directory_objects) == 1);
+
+	file_count = 0;
+	fm_directory_get_files(directory, get_files_cb, &data_dummy);
+
+	gtk_object_unref(GTK_OBJECT(directory));
+
+	g_assert(g_hash_table_size(directory_objects) == 0);
 }
 
 #endif /* !NAUTILUS_OMIT_SELF_CHECK */
diff --git a/src/file-manager/fm-vfs-directory.c b/src/file-manager/fm-vfs-directory.c
index 1dc003a48..8cfe3812b 100644
--- a/src/file-manager/fm-vfs-directory.c
+++ b/src/file-manager/fm-vfs-directory.c
@@ -2,7 +2,7 @@
    
    fm-vfs-directory.c: GNOME file manager directory model, VFS implementation.
  
-   Copyright (C) 1999 Eazel, Inc.
+   Copyright (C) 1999, 2000 Eazel, Inc.
   
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
@@ -30,28 +30,44 @@
 
 #include "fm-directory-protected.h"
 #include <libnautilus/nautilus-gtk-macros.h>
+#include <libgnomevfs/gnome-vfs.h>
 
 struct _FMVFSDirectoryDetails {
-	GList *files;
+	GnomeVFSURI *uri;
 
-  /*	GnomeVFSAsyncHandle *async_handle; */
+	FMFileList *files;
 };
 
 static void fm_vfs_directory_destroy (GtkObject *object);
 static void fm_vfs_directory_finalize (GtkObject *object);
+static void fm_vfs_directory_get_files (FMDirectory *directory,
+					FMFileListCallback callback,
+					gpointer callback_data);
 
 static GtkObjectClass *parent_class;
 
+#define METAFILE_NAME ".gnomad.xml"
+
+/* The process of reading a directory:
+
+     1) Read and parse the metafile.
+     2) Read the directory to notice changes.
+*/
+
 static void
 fm_vfs_directory_initialize_class (gpointer klass)
 {
 	GtkObjectClass *object_class;
+	FMDirectoryClass *abstract_directory_class;
 
 	object_class = GTK_OBJECT_CLASS (klass);
+	abstract_directory_class = FM_DIRECTORY_CLASS (klass);
 	parent_class = gtk_type_class (FM_TYPE_DIRECTORY);
 
 	object_class->destroy = fm_vfs_directory_destroy;
 	object_class->finalize = fm_vfs_directory_finalize;
+	
+	abstract_directory_class->get_files = fm_vfs_directory_get_files;
 }
 
 static void
@@ -59,7 +75,7 @@ fm_vfs_directory_initialize (gpointer object, gpointer klass)
 {
 	FMVFSDirectory *directory;
 
-	directory = FM_VFS_DIRECTORY(object);
+	directory = FM_VFS_DIRECTORY (object);
 
 	directory->details = g_new0 (FMVFSDirectoryDetails, 1);
 }
@@ -67,7 +83,7 @@ fm_vfs_directory_initialize (gpointer object, gpointer klass)
 static void
 fm_vfs_directory_destroy (GtkObject *object)
 {
-	NAUTILUS_CALL_PARENT_CLASS(GTK_OBJECT_CLASS, destroy, (object));
+	NAUTILUS_CALL_PARENT_CLASS (GTK_OBJECT_CLASS, destroy, (object));
 }
 
 static void
@@ -78,19 +94,60 @@ fm_vfs_directory_finalize (GtkObject *object)
 	directory = FM_VFS_DIRECTORY (object);
 	g_free (directory->details);
 	
-	NAUTILUS_CALL_PARENT_CLASS(GTK_OBJECT_CLASS, finalize, (object));
+	NAUTILUS_CALL_PARENT_CLASS (GTK_OBJECT_CLASS, finalize, (object));
 }
 
 NAUTILUS_DEFINE_GET_TYPE_FUNCTION(FMVFSDirectory, fm_vfs_directory, FM_TYPE_DIRECTORY)
 
+static void
+fm_vfs_opened_metafile (GnomeVFSAsyncHandle *handle,
+			GnomeVFSResult result,
+			gpointer callback_data)
+{
+}
+
 FMVFSDirectory *
 fm_vfs_directory_new (const char* uri)
 {
 	FMVFSDirectory *directory;
+	GnomeVFSURI *vfs_uri;
+	GnomeVFSURI *metafile_uri;
+	GnomeVFSAsyncHandle *metafile_handle;
+	GnomeVFSResult result;
+
+	vfs_uri = gnome_vfs_uri_new (uri);
+	if (vfs_uri == NULL)
+		return NULL;
+
+	metafile_uri = gnome_vfs_uri_append_path (vfs_uri, METAFILE_NAME);
+	if (metafile_uri == NULL)
+		return NULL;
 
 	directory = gtk_type_new (FM_TYPE_VFS_DIRECTORY);
 
-	FM_DIRECTORY(directory)->details->hash_table_key = g_strdup(uri);
+	FM_DIRECTORY (directory)->details->hash_table_key = g_strdup (uri);
+
+	directory->details->uri = vfs_uri;
+
+	result = gnome_vfs_async_open_uri (&metafile_handle, metafile_uri, GNOME_VFS_OPEN_READ,
+					   fm_vfs_opened_metafile, directory);
 
 	return directory;
 }
+
+static void
+fm_vfs_directory_get_files (FMDirectory *abstract_directory,
+			    FMFileListCallback callback,
+			    gpointer callback_data)
+{
+	FMVFSDirectory *directory;
+
+	g_return_if_fail (FM_IS_VFS_DIRECTORY (abstract_directory));
+	g_return_if_fail (callback != NULL);
+
+	directory = FM_VFS_DIRECTORY (abstract_directory);
+	if (directory->details->files != NULL)
+		(* callback) (abstract_directory,
+			      directory->details->files,
+			      callback_data);
+}
diff --git a/src/nautilus-main.c b/src/nautilus-main.c
index b558b8de1..fe6a23954 100644
--- a/src/nautilus-main.c
+++ b/src/nautilus-main.c
@@ -4,6 +4,7 @@
  *  Nautilus
  *
  *  Copyright (C) 1999, 2000 Red Hat, Inc.
+ *  Copyright (C) 1999, 2000 Eazel, Inc.
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU General Public License as
@@ -19,14 +20,19 @@
  *  along with this library; if not, write to the Free Software
  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  *
- *  Author: Elliot Lee <sopwith@redhat.com>
+ *  Authors: Elliot Lee <sopwith@redhat.com>,
+ *           Darin Adler <darin@eazel.com>,
+ *           John Sullivan <sullivan@eazel.com>
  *
  */
+
 /* ntl-main.c: Implementation of the routines that drive program lifecycle and main window creation/destruction. */
 
 #include "config.h"
 #include "nautilus.h"
-#include "nautilus-self-checks.h"
+#include "nautilus-self-check-functions.h"
+#include <libnautilus/nautilus-lib-self-check-functions.h>
+#include <libnautilus/nautilus-self-checks.h>
 
 int main(int argc, char *argv[])
 {
@@ -34,7 +40,7 @@ int main(int argc, char *argv[])
   CORBA_Environment ev;
   CORBA_ORB orb;
 #if !defined (NAUTILUS_OMIT_SELF_CHECK)
-  int check = FALSE;
+  gboolean check = FALSE;
 #endif
   const char **args;
 
@@ -61,17 +67,22 @@ int main(int argc, char *argv[])
   args = poptGetArgs (ctx);
 
 #if !defined (NAUTILUS_OMIT_SELF_CHECK)
-  if (check)
-    nautilus_run_all_self_checks();
-  else
+  if (check) {
+    /* Run the checks for nautilus and libnautilus. */
+    nautilus_run_self_checks ();
+    nautilus_run_lib_self_checks ();
+    if (nautilus_self_checks_failed ())
+      return 1;
+  } else
 #endif
   {
     nautilus_app_init (args ? args[0] : NULL);
+
     bonobo_main();
-  }
 
-  /* One last chance for cleanup before program finishes. */
-  nautilus_app_exiting();
+    /* One last chance for cleanup before program finishes. */
+    nautilus_app_exiting();
+  }
 
   return 0;
 }
diff --git a/src/nautilus-self-checks.c b/src/nautilus-self-check-functions.c
index cfa84c565..04fe6bcd4 100644
--- a/src/nautilus-self-checks.c
+++ b/src/nautilus-self-check-functions.c
@@ -1,8 +1,9 @@
 /* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
    
-   nautilus-self-checks.c: The self-check framework.
+   nautilus-self-check-functions.c: Wrapper for all self check functions
+   in Nautilus proper.
  
-   Copyright (C) 1999 Eazel, Inc.
+   Copyright (C) 1999, 2000 Eazel, Inc.
   
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
@@ -28,14 +29,11 @@
 
 #if ! defined (NAUTILUS_OMIT_SELF_CHECK)
 
-#include "nautilus-self-checks.h"
-
 #include "nautilus-self-check-functions.h"
 
-void nautilus_run_all_self_checks()
+void nautilus_run_self_checks()
 {
-	self_check_fm_directory();
-	self_check_gdk_extensions();
+	nautilus_self_check_fm_directory();
 }
 
 #endif /* ! NAUTILUS_OMIT_SELF_CHECK */
diff --git a/src/nautilus-self-check-functions.h b/src/nautilus-self-check-functions.h
index 33e872308..6c11cf9bc 100644
--- a/src/nautilus-self-check-functions.h
+++ b/src/nautilus-self-check-functions.h
@@ -1,9 +1,9 @@
 /* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
 
-   nautilus-self-check-functions.h: Prototypes for all the functions
-   called by the self-check framework.
+   nautilus-self-check-functions.h: Wrapper and prototypes for all self
+   check functions in Nautilus proper.
  
-   Copyright (C) 1999 Eazel, Inc.
+   Copyright (C) 1999, 2000 Eazel, Inc.
   
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
@@ -23,6 +23,8 @@
    Author: Darin Adler <darin@eazel.com>
 */
 
+void nautilus_run_self_checks (void);
+
 /* Putting the prototypes for these self-check functions in each
    header file for the files they are defined in would make compiling
    the self-check framework take way too long (since one file would
@@ -31,5 +33,4 @@
    So we put the prototypes here instead.
 */
 
-void self_check_fm_directory(void);
-void self_check_gdk_extensions(void);
+void nautilus_self_check_fm_directory (void);
diff --git a/src/ntl-main.c b/src/ntl-main.c
index b558b8de1..fe6a23954 100644
--- a/src/ntl-main.c
+++ b/src/ntl-main.c
@@ -4,6 +4,7 @@
  *  Nautilus
  *
  *  Copyright (C) 1999, 2000 Red Hat, Inc.
+ *  Copyright (C) 1999, 2000 Eazel, Inc.
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU General Public License as
@@ -19,14 +20,19 @@
  *  along with this library; if not, write to the Free Software
  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  *
- *  Author: Elliot Lee <sopwith@redhat.com>
+ *  Authors: Elliot Lee <sopwith@redhat.com>,
+ *           Darin Adler <darin@eazel.com>,
+ *           John Sullivan <sullivan@eazel.com>
  *
  */
+
 /* ntl-main.c: Implementation of the routines that drive program lifecycle and main window creation/destruction. */
 
 #include "config.h"
 #include "nautilus.h"
-#include "nautilus-self-checks.h"
+#include "nautilus-self-check-functions.h"
+#include <libnautilus/nautilus-lib-self-check-functions.h>
+#include <libnautilus/nautilus-self-checks.h>
 
 int main(int argc, char *argv[])
 {
@@ -34,7 +40,7 @@ int main(int argc, char *argv[])
   CORBA_Environment ev;
   CORBA_ORB orb;
 #if !defined (NAUTILUS_OMIT_SELF_CHECK)
-  int check = FALSE;
+  gboolean check = FALSE;
 #endif
   const char **args;
 
@@ -61,17 +67,22 @@ int main(int argc, char *argv[])
   args = poptGetArgs (ctx);
 
 #if !defined (NAUTILUS_OMIT_SELF_CHECK)
-  if (check)
-    nautilus_run_all_self_checks();
-  else
+  if (check) {
+    /* Run the checks for nautilus and libnautilus. */
+    nautilus_run_self_checks ();
+    nautilus_run_lib_self_checks ();
+    if (nautilus_self_checks_failed ())
+      return 1;
+  } else
 #endif
   {
     nautilus_app_init (args ? args[0] : NULL);
+
     bonobo_main();
-  }
 
-  /* One last chance for cleanup before program finishes. */
-  nautilus_app_exiting();
+    /* One last chance for cleanup before program finishes. */
+    nautilus_app_exiting();
+  }
 
   return 0;
 }