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>
diff --git a/attr.c b/attr.c
index 8d778f1..1293993 100644
--- a/attr.c
+++ b/attr.c
@@ -336,13 +336,70 @@
 	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 0625112..fc3a506 100644
--- a/entry.c
+++ b/entry.c
@@ -112,6 +112,16 @@
 		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 @@
 				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 fe1dfd0..0807d9f 100755
--- a/t/t0020-crlf.sh
+++ b/t/t0020-crlf.sh
@@ -290,4 +290,85 @@
 	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