combine-diff: respect textconv attributes

When doing a combined diff, we did not respect textconv attributes at
all. This generally lead to us printing "Binary files differ" when we
could show a combined diff of the converted text.

This patch converts file contents according to textconv attributes. The
implementation is slightly ugly; because the textconv code is tightly
linked with the diff_filespec code, we temporarily create a diff_filespec
during conversion. In practice, though, this should not create a
performance problem.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/combine-diff.c b/combine-diff.c
index 94a207f47783bf37e2fda5281914def3f449c2fd..be67cfcd45469497f81e0c36ed87a11fd409daee 100644 (file)
--- a/combine-diff.c
+++ b/combine-diff.c
@@ -93,7 +93,9 @@ struct sline {
        unsigned long *p_lno;
 };
 
-static char *grab_blob(const unsigned char *sha1, unsigned int mode, unsigned long *size)
+static char *grab_blob(const unsigned char *sha1, unsigned int mode,
+                      unsigned long *size, struct userdiff_driver *textconv,
+                      const char *path)
 {
        char *blob;
        enum object_type type;
@@ -106,6 +108,11 @@ static char *grab_blob(const unsigned char *sha1, unsigned int mode, unsigned lo
                /* deleted blob */
                *size = 0;
                return xcalloc(1, 1);
+       } else if (textconv) {
+               struct diff_filespec *df = alloc_filespec(path);
+               fill_filespec(df, sha1, mode);
+               *size = fill_textconv(textconv, df, &blob);
+               free_filespec(df);
        } else {
                blob = read_sha1_file(sha1, &type, size);
                if (type != OBJ_BLOB)
@@ -205,7 +212,9 @@ static void consume_line(void *state_, char *line, unsigned long len)
 static void combine_diff(const unsigned char *parent, unsigned int mode,
                         mmfile_t *result_file,
                         struct sline *sline, unsigned int cnt, int n,
-                        int num_parent, int result_deleted)
+                        int num_parent, int result_deleted,
+                        struct userdiff_driver *textconv,
+                        const char *path)
 {
        unsigned int p_lno, lno;
        unsigned long nmask = (1UL << n);
@@ -218,7 +227,7 @@ static void combine_diff(const unsigned char *parent, unsigned int mode,
        if (result_deleted)
                return; /* result deleted */
 
-       parent_file.ptr = grab_blob(parent, mode, &sz);
+       parent_file.ptr = grab_blob(parent, mode, &sz, textconv, path);
        parent_file.size = sz;
        memset(&xpp, 0, sizeof(xpp));
        xpp.flags = 0;
@@ -771,16 +780,20 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
        int working_tree_file = is_null_sha1(elem->sha1);
        mmfile_t result_file;
        struct userdiff_driver *userdiff;
+       struct userdiff_driver *textconv = NULL;
        int is_binary;
 
        context = opt->context;
        userdiff = userdiff_find_by_path(elem->path);
        if (!userdiff)
                userdiff = userdiff_find_by_name("default");
+       if (DIFF_OPT_TST(opt, ALLOW_TEXTCONV))
+               textconv = userdiff_get_textconv(userdiff);
 
        /* Read the result of merge first */
        if (!working_tree_file)
-               result = grab_blob(elem->sha1, elem->mode, &result_size);
+               result = grab_blob(elem->sha1, elem->mode, &result_size,
+                                  textconv, elem->path);
        else {
                /* Used by diff-tree to read from the working tree */
                struct stat st;
@@ -803,9 +816,16 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
                } else if (S_ISDIR(st.st_mode)) {
                        unsigned char sha1[20];
                        if (resolve_gitlink_ref(elem->path, "HEAD", sha1) < 0)
-                               result = grab_blob(elem->sha1, elem->mode, &result_size);
+                               result = grab_blob(elem->sha1, elem->mode,
+                                                  &result_size, NULL, NULL);
                        else
-                               result = grab_blob(sha1, elem->mode, &result_size);
+                               result = grab_blob(sha1, elem->mode,
+                                                  &result_size, NULL, NULL);
+               } else if (textconv) {
+                       struct diff_filespec *df = alloc_filespec(elem->path);
+                       fill_filespec(df, null_sha1, st.st_mode);
+                       result_size = fill_textconv(textconv, df, &result);
+                       free_filespec(df);
                } else if (0 <= (fd = open(elem->path, O_RDONLY))) {
                        size_t len = xsize_t(st.st_size);
                        ssize_t done;
@@ -862,7 +882,9 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
                }
        }
 
-       if (userdiff->binary != -1)
+       if (textconv)
+               is_binary = 0;
+       else if (userdiff->binary != -1)
                is_binary = userdiff->binary;
        else {
                is_binary = buffer_is_binary(result, result_size);
@@ -871,7 +893,7 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
                        unsigned long size;
                        buf = grab_blob(elem->parent[i].sha1,
                                        elem->parent[i].mode,
-                                       &size);
+                                       &size, NULL, NULL);
                        if (buffer_is_binary(buf, size))
                                is_binary = 1;
                        free(buf);
@@ -932,7 +954,8 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
                        combine_diff(elem->parent[i].sha1,
                                     elem->parent[i].mode,
                                     &result_file, sline,
-                                    cnt, i, num_parent, result_deleted);
+                                    cnt, i, num_parent, result_deleted,
+                                    textconv, elem->path);
        }
 
        show_hunks = make_hunks(sline, cnt, num_parent, dense);

diff --git a/t/t4048-diff-combined-binary.sh b/t/t4048-diff-combined-binary.sh
index a943994b07e458e6754b39de781ce7c277b60274..87a8949500bbfb450624de27f17f1300761cf20e 100755 (executable)
--- a/t/t4048-diff-combined-binary.sh
+++ b/t/t4048-diff-combined-binary.sh
@@ -110,4 +110,103 @@ test_expect_success 'diff --cc respects binary attribute' '
        test_cmp expect actual
 '
 
+test_expect_success 'setup textconv attribute' '
+       echo "text diff=upcase" >.gitattributes &&
+       git config diff.upcase.textconv "tr a-z A-Z <"
+'
+
+cat >expect <<'EOF'
+resolved
+
+diff --git a/text b/text
+index 2bdf67a..2ab19ae 100644
+--- a/text
++++ b/text
+@@ -1 +1 @@
+-THREE
++RESOLVED
+resolved
+
+diff --git a/text b/text
+index f719efd..2ab19ae 100644
+--- a/text
++++ b/text
+@@ -1 +1 @@
+-TWO
++RESOLVED
+EOF
+test_expect_success 'diff -m respects textconv attribute' '
+       git show --format=%s -m >actual &&
+       test_cmp expect actual
+'
+
+cat >expect <<'EOF'
+resolved
+
+diff --combined text
+index 2bdf67a,f719efd..2ab19ae
+--- a/text
++++ b/text
+@@@ -1,1 -1,1 +1,1 @@@
+- THREE
+ -TWO
+++RESOLVED
+EOF
+test_expect_success 'diff -c respects textconv attribute' '
+       git show --format=%s -c >actual &&
+       test_cmp expect actual
+'
+
+cat >expect <<'EOF'
+resolved
+
+diff --cc text
+index 2bdf67a,f719efd..2ab19ae
+--- a/text
++++ b/text
+@@@ -1,1 -1,1 +1,1 @@@
+- THREE
+ -TWO
+++RESOLVED
+EOF
+test_expect_success 'diff --cc respects textconv attribute' '
+       git show --format=%s --cc >actual &&
+       test_cmp expect actual
+'
+
+cat >expect <<'EOF'
+diff --combined text
+index 2bdf67a,f719efd..2ab19ae
+--- a/text
++++ b/text
+@@@ -1,1 -1,1 +1,1 @@@
+- three
+ -two
+++resolved
+EOF
+test_expect_success 'diff-tree plumbing does not respect textconv' '
+       git diff-tree HEAD -c -p >full &&
+       tail -n +2 full >actual &&
+       test_cmp expect actual
+'
+
+cat >expect <<'EOF'
+diff --cc text
+index 2bdf67a,f719efd..0000000
+--- a/text
++++ b/text
+@@@ -1,1 -1,1 +1,5 @@@
+++<<<<<<< HEAD
+ +THREE
+++=======
++ TWO
+++>>>>>>> MASTER
+EOF
+test_expect_success 'diff --cc respects textconv on worktree file' '
+       git reset --hard HEAD^ &&
+       test_must_fail git merge master &&
+       git diff >actual &&
+       test_cmp expect actual
+'
+
 test_done