attr.c: read .gitattributes from index as well.

This makes .gitattributes files to be read from the index when
they are not checked out to the work tree.  This is in line with
the way we always allowed low-level tools to operate in sparsely
checked out work tree in a reasonable way.

It swaps the order of new file creation and converting the blob
to work tree representation; otherwise when we are in the middle
of checking out .gitattributes we would notice an empty but
unwritten .gitattributes file in the work tree and will ignore
the copy in the index.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

3 files changed, 150 insertions, 11 deletions

diff --git a/attr.c b/attr.c
index 8d778f1d26..129399310a 100644
--- a/attr.c
+++ b/attr.c
@@ -336,13 +336,70 @@ static struct attr_stack *read_attr_from_file(const char *path, int macro_ok)
 	return res;
 }
 
+static void *read_index_data(const char *path)
+{
+	int pos, len;
+	unsigned long sz;
+	enum object_type type;
+	void *data;
+
+	len = strlen(path);
+	pos = cache_name_pos(path, len);
+	if (pos < 0) {
+		/*
+		 * We might be in the middle of a merge, in which
+		 * case we would read stage #2 (ours).
+		 */
+		int i;
+		for (i = -pos - 1;
+		     (pos < 0 && i < active_nr &&
+		      !strcmp(active_cache[i]->name, path));
+		     i++)
+			if (ce_stage(active_cache[i]) == 2)
+				pos = i;
+	}
+	if (pos < 0)
+		return NULL;
+	data = read_sha1_file(active_cache[pos]->sha1, &type, &sz);
+	if (!data || type != OBJ_BLOB) {
+		free(data);
+		return NULL;
+	}
+	return data;
+}
+
 static struct attr_stack *read_attr(const char *path, int macro_ok)
 {
 	struct attr_stack *res;
+	char *buf, *sp;
+	int lineno = 0;
 
 	res = read_attr_from_file(path, macro_ok);
-	if (!res)
-		res = xcalloc(1, sizeof(*res));
+	if (res)
+		return res;
+
+	res = xcalloc(1, sizeof(*res));
+
+	/*
+	 * There is no checked out .gitattributes file there, but
+	 * we might have it in the index.  We allow operation in a
+	 * sparsely checked out work tree, so read from it.
+	 */
+	buf = read_index_data(path);
+	if (!buf)
+		return res;
+
+	for (sp = buf; *sp; ) {
+		char *ep;
+		int more;
+		for (ep = sp; *ep && *ep != '\n'; ep++)
+			;
+		more = (*ep == '\n');
+		*ep = '\0';
+		handle_attr_line(res, sp, path, ++lineno, macro_ok);
+		sp = ep + more;
+	}
+	free(buf);
 	return res;
 }
 
diff --git a/entry.c b/entry.c
index 0625112339..fc3a506ece 100644
--- a/entry.c
+++ b/entry.c
@@ -112,6 +112,16 @@ static int write_entry(struct cache_entry *ce, char *path, const struct checkout
 		if (!new)
 			return error("git-checkout-index: unable to read sha1 file of %s (%s)",
 				path, sha1_to_hex(ce->sha1));
+
+		/*
+		 * Convert from git internal format to working tree format
+		 */
+		buf = convert_to_working_tree(ce->name, new, &size);
+		if (buf) {
+			free(new);
+			new = buf;
+		}
+
 		if (to_tempfile) {
 			strcpy(path, ".merge_file_XXXXXX");
 			fd = mkstemp(path);
@@ -123,15 +133,6 @@ static int write_entry(struct cache_entry *ce, char *path, const struct checkout
 				path, strerror(errno));
 		}
 
-		/*
-		 * Convert from git internal format to working tree format
-		 */
-		buf = convert_to_working_tree(ce->name, new, &size);
-		if (buf) {
-			free(new);
-			new = buf;
-		}
-
 		wrote = write_in_full(fd, new, size);
 		close(fd);
 		free(new);
diff --git a/t/t0020-crlf.sh b/t/t0020-crlf.sh
index fe1dfd08a0..0807d9f01a 100755
--- a/t/t0020-crlf.sh
+++ b/t/t0020-crlf.sh
@@ -290,4 +290,85 @@ test_expect_success '.gitattributes says two and three are text' '
 	fi
 '
 
+test_expect_success 'in-tree .gitattributes (1)' '
+
+	echo "one -crlf" >>.gitattributes &&
+	git add .gitattributes &&
+	git commit -m "Add .gitattributes" &&
+
+	rm -rf tmp one dir .gitattributes patch.file three &&
+	git read-tree --reset -u HEAD &&
+
+	if remove_cr one >/dev/null
+	then
+		echo "Eh? one should not have CRLF"
+		false
+	else
+		: happy
+	fi &&
+	remove_cr three >/dev/null || {
+		echo "Eh? three should still have CRLF"
+		false
+	}
+'
+
+test_expect_success 'in-tree .gitattributes (2)' '
+
+	rm -rf tmp one dir .gitattributes patch.file three &&
+	git read-tree --reset HEAD &&
+	git checkout-index -f -q -u -a &&
+
+	if remove_cr one >/dev/null
+	then
+		echo "Eh? one should not have CRLF"
+		false
+	else
+		: happy
+	fi &&
+	remove_cr three >/dev/null || {
+		echo "Eh? three should still have CRLF"
+		false
+	}
+'
+
+test_expect_success 'in-tree .gitattributes (3)' '
+
+	rm -rf tmp one dir .gitattributes patch.file three &&
+	git read-tree --reset HEAD &&
+	git checkout-index -u .gitattributes &&
+	git checkout-index -u one dir/two three &&
+
+	if remove_cr one >/dev/null
+	then
+		echo "Eh? one should not have CRLF"
+		false
+	else
+		: happy
+	fi &&
+	remove_cr three >/dev/null || {
+		echo "Eh? three should still have CRLF"
+		false
+	}
+'
+
+test_expect_success 'in-tree .gitattributes (4)' '
+
+	rm -rf tmp one dir .gitattributes patch.file three &&
+	git read-tree --reset HEAD &&
+	git checkout-index -u one dir/two three &&
+	git checkout-index -u .gitattributes &&
+
+	if remove_cr one >/dev/null
+	then
+		echo "Eh? one should not have CRLF"
+		false
+	else
+		: happy
+	fi &&
+	remove_cr three >/dev/null || {
+		echo "Eh? three should still have CRLF"
+		false
+	}
+'
+
 test_done