Merge branch 'soft-hyphen' into 'master'

Soft hyphen

See merge request GNOME/pango!68

7 files changed, 403 insertions, 3 deletions

diff --git a/pango/break.c b/pango/break.c
index 11f4079e..13ccbdaf 100644
--- a/pango/break.c
+++ b/pango/break.c
@@ -984,6 +984,7 @@ pango_default_break (const gchar   *text,
       attrs[i].is_char_break = FALSE;
       attrs[i].is_line_break = FALSE;
       attrs[i].is_mandatory_break = FALSE;
+      attrs[i].is_soft_hyphen = FALSE;
 
       /* Rule LB1:
 	 assign a line breaking class to each code point of the input. */
@@ -1364,9 +1365,15 @@ pango_default_break (const gchar   *text,
 
 	    case BREAK_ALLOWED:
 	      attrs[i].is_line_break = TRUE;
-	      break;
+              /* fall through */
 
 	    case BREAK_ALREADY_HANDLED:
+              if (attrs[i].is_line_break)
+                {
+                  /* After Soft Hyphen */
+                  if (prev_wc == 0x00AD)
+                    attrs[i].is_soft_hyphen = TRUE;
+                }
 	      break;
 
 	    default:
diff --git a/pango/pango-break.h b/pango/pango-break.h
index 92af390b..66d81631 100644
--- a/pango/pango-break.h
+++ b/pango/pango-break.h
@@ -79,6 +79,9 @@ G_BEGIN_DECLS
  * This flag implements Unicode's
  * <ulink url="http://www.unicode.org/reports/tr29/">Word
  * Boundaries</ulink> semantics. (Since: 1.22)
+ * @is_soft_hyphen: is a line break due to a Soft Hyphen (0x00AD).
+ *     This indicates a position where a hyphen should be inserted
+ *     if the break is taken.
  *
  * The #PangoLogAttr structure stores information
  * about the attributes of a single character.
@@ -86,7 +89,6 @@ G_BEGIN_DECLS
 struct _PangoLogAttr
 {
   guint is_line_break : 1;      /* Can break line in front of character */
-
   guint is_mandatory_break : 1; /* Must break line in front of character */
 
   guint is_char_break : 1;      /* Can break here when doing char wrap */
@@ -130,6 +132,7 @@ struct _PangoLogAttr
 
   /* Word boundary as defined by UAX#29 */
   guint is_word_boundary : 1;	/* is NOT in the middle of a word */
+  guint is_soft_hyphen : 1;	/* line break due to a soft hyphen */
 };
 
 /* Determine information about cluster/word/line breaks in a string
diff --git a/pango/pango-layout.c b/pango/pango-layout.c
index 1ba614e1..baf81bd4 100644
--- a/pango/pango-layout.c
+++ b/pango/pango-layout.c
@@ -3376,6 +3376,66 @@ insert_run (PangoLayoutLine *line,
   line->length += run_item->length;
 }
 
+static void
+advance_iterator_to (PangoAttrIterator *iter,
+                     int                new_index)
+{
+  int start, end;
+
+  do
+    {
+      pango_attr_iterator_range (iter, &start, &end);
+      if (end > new_index)
+        break;
+    }
+  while (pango_attr_iterator_next (iter));
+}
+
+static PangoLayoutRun *
+create_hyphen_run (PangoLayout *layout,
+                   PangoItem   *item,
+                   int          offset)
+{
+  PangoLayoutRun *hyphen;
+  GList *items;
+  const char *hyphen_text = "-";
+  PangoAttrList *attrs;
+  PangoAttrIterator *iter;
+  GSList *list, *l;
+  PangoAttrList *run_attrs;
+
+  run_attrs = pango_attr_list_new ();
+
+  attrs = pango_layout_get_effective_attributes (layout);
+  iter = pango_attr_list_get_iterator (attrs);
+
+  advance_iterator_to (iter, offset);
+  list = pango_attr_iterator_get_attrs (iter);
+  for (l = list; l; l = l->next)
+    {
+      PangoAttribute *attr = l->data;
+      attr->start_index = 0;
+      attr->end_index = G_MAXINT;
+      pango_attr_list_insert (attrs, attr);
+    }
+  g_slist_free (list);
+  
+  hyphen = g_slice_new (PangoGlyphItem);
+  hyphen->glyphs = pango_glyph_string_new ();
+  items = pango_itemize (layout->context, hyphen_text, 0, strlen (hyphen_text), attrs, NULL);
+  g_assert (items->next == NULL);
+  hyphen->item = items->data;
+  hyphen->item->offset = offset;
+  g_list_free (items);
+  pango_shape (hyphen_text, strlen (hyphen_text), &hyphen->item->analysis, hyphen->glyphs);
+
+  pango_attr_iterator_destroy (iter);
+  pango_attr_list_unref (attrs);
+  pango_attr_list_unref (run_attrs);
+
+  return hyphen;
+}
+
 #if 0
 # define DEBUG debug
 void
@@ -3483,6 +3543,8 @@ process_item (PangoLayout     *layout,
       int break_num_chars = num_chars;
       int break_width = width;
       int orig_width = width;
+      int break_extra_width;
+      int hyphen_width;
       gboolean retrying_with_char_breaks = FALSE;
 
       if (processing_new_item)
@@ -3492,13 +3554,22 @@ process_item (PangoLayout     *layout,
 	  pango_glyph_item_get_logical_widths (&glyph_item, layout->text, state->log_widths);
 	}
 
+      {
+        PangoLayoutRun *run;
+
+        run = create_hyphen_run (layout, item, state->start_offset);
+        hyphen_width = pango_glyph_string_get_width (run->glyphs);
+        pango_glyph_item_free (run);
+      }
+
     retry_break:
 
       /* See how much of the item we can stuff in the line. */
       width = 0;
+      break_extra_width = 0;
       for (num_chars = 0; num_chars < item->num_chars; num_chars++)
 	{
-	  if (width > state->remaining_width && break_num_chars < item->num_chars)
+	  if (width + break_extra_width > state->remaining_width && break_num_chars < item->num_chars)
 	    break;
 
 	  /* If there are no previous runs we have to take care to grab at least one char. */
@@ -3507,6 +3578,12 @@ process_item (PangoLayout     *layout,
 	    {
 	      break_num_chars = num_chars;
 	      break_width = width;
+
+              /* Check whether to insert a hyphen */
+              if (layout->log_attrs[state->start_offset + num_chars].is_soft_hyphen)
+                break_extra_width = hyphen_width;
+              else
+                break_extra_width = 0;
 	    }
 
 	  width += state->log_widths[state->log_widths_offset + num_chars];
@@ -3543,6 +3620,14 @@ process_item (PangoLayout     *layout,
 	  if (break_num_chars == item->num_chars)
 	    {
 	      insert_run (line, state, item, TRUE);
+              if (layout->log_attrs[state->start_offset + break_num_chars].is_soft_hyphen)
+                {
+                  PangoLayoutRun *run;
+
+                  run = create_hyphen_run (layout, item, state->start_offset + break_num_chars);
+                  line->runs = g_slist_prepend (line->runs, run);
+	          state->remaining_width -= pango_glyph_string_get_width (run->glyphs);
+                }
 
 	      return BREAK_ALL_FIT;
 	    }
@@ -3569,6 +3654,15 @@ process_item (PangoLayout     *layout,
 	      /* Shaped items should never be broken */
 	      g_assert (!shape_set);
 
+              if (layout->log_attrs[state->start_offset + break_num_chars].is_soft_hyphen)
+                {
+                  PangoLayoutRun *run;
+
+                  run = create_hyphen_run (layout, item, state->start_offset + break_num_chars);
+                  line->runs = g_slist_prepend (line->runs, run);
+	          state->remaining_width -= pango_glyph_string_get_width (run->glyphs);
+                }
+
 	      return BREAK_SOME_FIT;
 	    }
 	}
diff --git a/tests/breaks/one.break b/tests/breaks/one.break
new file mode 100644
index 00000000..f30dc534
--- /dev/null
+++ b/tests/breaks/one.break
@@ -0,0 +1 @@
+abc/def ghi­jkl. Bla
diff --git a/tests/breaks/one.expected b/tests/breaks/one.expected
new file mode 100644
index 00000000..90ea8d18
--- /dev/null
+++ b/tests/breaks/one.expected
@@ -0,0 +1,5 @@
+Text:        a b c /  d e f [ ]  g h i [0xad]   j k l . [ ]  B l a [0x0a]  
+Breaks:     c c c c lc c c c   lc c c c      lhc c c c c   lc c c c      Lc
+Whitespace:                x                           x          w      w 
+Words:      s     e s      e   s                     e     s      e        
+Sentences:  s                                          e   s      e        
diff --git a/tests/meson.build b/tests/meson.build
index 7df7a999..50176c3d 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -22,6 +22,7 @@ tests = [
   [ 'testcolor' ],
   [ 'testscript' ],
   [ 'cxx-test', [ 'cxx-test.cpp' ] ],
+  [ 'test-break' ],
 ]
 
 if build_pangoft2
diff --git a/tests/test-break.c b/tests/test-break.c
new file mode 100644
index 00000000..9f069c09
--- /dev/null
+++ b/tests/test-break.c
@@ -0,0 +1,289 @@
+/* Pango
+ * test-break.c: Test Pango line breaking
+ *
+ * Copyright (C) 2019 Red Hat, Inc
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include <glib.h>
+#include <string.h>
+#include <locale.h>
+
+#ifndef G_OS_WIN32
+#include <unistd.h>
+#endif
+
+#include "config.h"
+#include <pango/pangocairo.h>
+#include "test-common.h"
+
+
+static PangoContext *context;
+
+static void
+test_file (const gchar *filename, GString *string)
+{
+  gchar *contents;
+  gsize  length;
+  GError *error = NULL;
+  PangoLogAttr *attrs;
+  PangoLanguage *lang;
+  int len;
+  char *p;
+  int i;
+  GString *s1, *s2, *s3, *s4;
+  int m;
+
+  if (!g_file_get_contents (filename, &contents, &length, &error))
+    {
+      fprintf (stderr, "%s\n", error->message);
+      g_error_free (error);
+      return;
+    }
+
+  len = g_utf8_strlen (contents, -1) + 1;
+  attrs = g_new (PangoLogAttr, len);
+
+  lang = pango_language_from_string ("en");
+
+  pango_get_log_attrs (contents, length, -1, lang, attrs, len);
+
+  s1 = g_string_new ("Breaks: ");
+  s2 = g_string_new ("Whitespace: ");
+  s3 = g_string_new ("Words:");
+  s4 = g_string_new ("Sentences:");
+
+  g_string_append (string, "Text: ");
+
+  m = MAX (MAX (s1->len, s2->len), MAX (s3->len, s4->len));
+
+  g_string_append_printf (s1, "%*s", (int)(m - s1->len), "");
+  g_string_append_printf (s2, "%*s", (int)(m - s2->len), "");
+  g_string_append_printf (s3, "%*s", (int)(m - s3->len), "");
+  g_string_append_printf (s4, "%*s", (int)(m - s4->len), "");
+  g_string_append_printf (string, "%*s", (int)(m - strlen ("Text: ")), "");
+
+  for (i = 0, p = contents; i < len; i++, p = g_utf8_next_char (p))
+    {
+      PangoLogAttr log = attrs[i];
+      int b = 0;
+      int w = 0;
+      int o = 0;
+      int s = 0;
+
+      if (log.is_mandatory_break)
+        {
+          g_string_append (s1, "L");
+          b++;
+        }
+      else if (log.is_line_break)
+        {
+          g_string_append (s1, "l");
+          b++;
+        }
+      if (log.is_soft_hyphen)
+        {
+          g_string_append (s1, "h");
+          b++;
+        }
+      if (log.is_char_break)
+        {
+          g_string_append (s1, "c");
+          b++;
+        }
+
+      if (log.is_expandable_space)
+        {
+          g_string_append (s2, "x");
+          w++;
+        }
+      else if (log.is_white)
+        {
+          g_string_append (s2, "w");
+          w++;
+        }
+
+      if (log.is_word_start)
+        {
+          g_string_append (s3, "s");
+          o++;
+        }
+      if (log.is_word_end)
+        {
+          g_string_append (s3, "e");
+          o++;
+        }
+
+      if (log.is_sentence_start)
+        {
+          g_string_append (s4, "s");
+          s++;
+        }
+      if (log.is_sentence_end)
+        {
+          g_string_append (s4, "e");
+          s++;
+        }
+
+      m = MAX (MAX (b, w), MAX (o, s));
+
+      g_string_append_printf (string, "%*s", m, "");
+      g_string_append_printf (s1, "%*s", m - b, "");
+      g_string_append_printf (s2, "%*s", m - w, "");
+      g_string_append_printf (s3, "%*s", m - o, "");
+      g_string_append_printf (s4, "%*s", m - s, "");
+
+      if (i < len - 1)
+        {
+          gunichar ch = g_utf8_get_char (p);
+          if (ch == 0x20)
+            {
+              g_string_append (string, "[ ]");
+              g_string_append (s1, "   ");
+              g_string_append (s2, "   ");
+              g_string_append (s3, "   ");
+              g_string_append (s4, "   ");
+            }
+          else if (g_unichar_isprint (ch))
+            {
+              g_string_append_unichar (string, ch);
+              g_string_append (s1, " ");
+              g_string_append (s2, " ");
+              g_string_append (s3, " ");
+              g_string_append (s4, " ");
+            }
+          else
+            {
+              char *str = g_strdup_printf ("[%#04x]", ch);
+              g_string_append (string, str); 
+              g_string_append_printf (s1, "%*s", (int)strlen (str), "");
+              g_string_append_printf (s2, "%*s", (int)strlen (str), "");
+              g_string_append_printf (s3, "%*s", (int)strlen (str), "");
+              g_string_append_printf (s4, "%*s", (int)strlen (str), "");
+              g_free (str);
+            }
+        }
+    }
+  g_string_append (string, "\n");
+  g_string_append_len (string, s1->str, s1->len);
+  g_string_append (string, "\n");
+  g_string_append_len (string, s2->str, s2->len);
+  g_string_append (string, "\n");
+  g_string_append_len (string, s3->str, s3->len);
+  g_string_append (string, "\n");
+  g_string_append_len (string, s4->str, s4->len);
+  g_string_append (string, "\n");
+
+  g_string_free (s1, TRUE);
+  g_string_free (s2, TRUE);
+  g_string_free (s3, TRUE);
+  g_string_free (s4, TRUE);
+
+  g_free (attrs);
+  g_free (contents);
+}
+
+static gchar *
+get_expected_filename (const gchar *filename)
+{
+  gchar *f, *p, *expected;
+
+  f = g_strdup (filename);
+  p = strstr (f, ".break");
+  if (p)
+    *p = 0;
+  expected = g_strconcat (f, ".expected", NULL);
+
+  g_free (f);
+
+  return expected;
+}
+
+static void
+test_break (gconstpointer d)
+{
+  const gchar *filename = d;
+  gchar *expected_file;
+  GError *error = NULL;
+  GString *dump;
+  gchar *diff;
+
+  expected_file = get_expected_filename (filename);
+
+  dump = g_string_sized_new (0);
+
+  test_file (filename, dump);
+
+  //diff = diff_with_file (expected_file, dump->str, dump->len, &error);
+  g_assert_no_error (error);
+
+  if (diff && diff[0])
+    {
+      g_printerr ("Contents don't match expected contents:\n%s", diff);
+      g_test_fail ();
+      g_free (diff);
+    }
+
+  g_string_free (dump, TRUE);
+  g_free (expected_file);
+}
+
+int
+main (int argc, char *argv[])
+{
+  GDir *dir;
+  GError *error = NULL;
+  const gchar *name;
+  gchar *path;
+
+  g_setenv ("LC_ALL", "en_US.UTF-8", TRUE);
+  setlocale (LC_ALL, "");
+
+  g_test_init (&argc, &argv, NULL);
+
+  context = pango_context_new ();
+
+  /* allow to easily generate expected output for new test cases */
+  if (argc > 1)
+    {
+      GString *string;
+
+      string = g_string_sized_new (0);
+      test_file (argv[1], string);
+      printf ("%s", string->str);
+
+      return 0;
+    }
+
+  path = g_test_build_filename (G_TEST_DIST, "breaks", NULL);
+  dir = g_dir_open (path, 0, &error);
+  g_free (path);
+  g_assert_no_error (error);
+  while ((name = g_dir_read_name (dir)) != NULL)
+    {
+      if (!strstr (name, "break"))
+        continue;
+
+      path = g_strdup_printf ("/break/%s", name);
+      g_test_add_data_func_full (path, g_test_build_filename (G_TEST_DIST, "breaks", name, NULL),
+                                 test_break, g_free);
+      g_free (path);
+    }
+  g_dir_close (dir);
+
+  return g_test_run ();
+}