built-in diff: assorted updates.

"git diff(n)" without --base, --ours, etc. defaults to --cc,
which usually is the same as -p unless you are in the middle of
a conflicted merge, just like the shell script version.

"git diff(n) blobA blobB path" complains and dies.

"git diff(n) tree0 tree1 tree2...treeN" does combined diff that
shows a merge of tree1..treeN to result in tree0.

Giving "-c" option to any command that defaults to "--cc" turns
off dense-combined flag.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/builtin-diff.c b/builtin-diff.c
index 1968212..c543105 100644 (file)
--- a/builtin-diff.c
+++ b/builtin-diff.c
@@ -47,13 +47,17 @@ static int builtin_diff_files(struct rev_info *revs,
        }
        /*
         * Make sure there are NO revision (i.e. pending object) parameter,
-        * rev.max_count is reasonable (0 <= n <= 3),
-        * there is no other revision filtering parameters.
+        * specified rev.max_count is reasonable (0 <= n <= 3), and
+        * there is no other revision filtering parameter.
         */
        if (revs->pending_objects ||
            revs->min_age != -1 ||
-           revs->max_age != -1)
+           revs->max_age != -1 ||
+           3 < revs->max_count)
                usage(builtin_diff_usage);
+       if (revs->max_count < 0 &&
+           (revs->diffopt.output_format == DIFF_FORMAT_PATCH))
+               revs->combine_merges = revs->dense_combined_merges = 1;
        /*
         * Backward compatibility wart - "diff-files -s" used to
         * defeat the common diff option "-s" which asked for
@@ -178,9 +182,6 @@ static int builtin_diff_tree(struct rev_info *revs,
                             int argc, const char **argv,
                             struct object_list *ent)
 {
-       /* We saw two trees, ent[0] and ent[1].
-        * unless ent[0] is unintesting, they are swapped
-        */
        const unsigned char *(sha1[2]);
        int swap = 1;
        while (1 < argc) {
@@ -191,6 +192,10 @@ static int builtin_diff_tree(struct rev_info *revs,
                        usage(builtin_diff_usage);
                argv++; argc--;
        }
+
+       /* We saw two trees, ent[0] and ent[1].
+        * unless ent[0] is unintesting, they are swapped
+        */
        if (ent[0].item->flags & UNINTERESTING)
                swap = 0;
        sha1[swap] = ent[0].item->sha1;
@@ -200,6 +205,33 @@ static int builtin_diff_tree(struct rev_info *revs,
        return 0;
 }
 
+static int builtin_diff_combined(struct rev_info *revs,
+                                int argc, const char **argv,
+                                struct object_list *ent,
+                                int ents)
+{
+       const unsigned char (*parent)[20];
+       int i;
+
+       while (1 < argc) {
+               const char *arg = argv[1];
+               if (!strcmp(arg, "--raw"))
+                       revs->diffopt.output_format = DIFF_FORMAT_RAW;
+               else
+                       usage(builtin_diff_usage);
+               argv++; argc--;
+       }
+       if (!revs->dense_combined_merges && !revs->combine_merges)
+               revs->dense_combined_merges = revs->combine_merges = 1;
+       parent = xmalloc(ents * sizeof(*parent));
+       /* Again, the revs are all reverse */
+       for (i = 0; i < ents; i++)
+               memcpy(parent + i, ent[ents - 1 - i].item->sha1, 20);
+       diff_tree_combined(parent[0], parent + 1, ents - 1,
+                          revs->dense_combined_merges, revs);
+       return 0;
+}
+
 static void add_head(struct rev_info *revs)
 {
        unsigned char sha1[20];
@@ -215,7 +247,7 @@ static void add_head(struct rev_info *revs)
 int cmd_diff(int argc, const char **argv, char **envp)
 {
        struct rev_info rev;
-       struct object_list *list, ent[2];
+       struct object_list *list, ent[100];
        int ents = 0, blobs = 0, paths = 0;
        const char *path = NULL;
        struct blobinfo blob[2];
@@ -273,8 +305,9 @@ int cmd_diff(int argc, const char **argv, char **envp)
                if (!strcmp(obj->type, commit_type))
                        obj = &((struct commit *)obj)->tree->object;
                if (!strcmp(obj->type, tree_type)) {
-                       if (2 <= ents)
-                               die("more than two trees given: '%s'", name);
+                       if (ARRAY_SIZE(ent) <= ents)
+                               die("more than %d trees given: '%s'",
+                                   ARRAY_SIZE(ent), name);
                        obj->flags |= flags;
                        ent[ents].item = obj;
                        ent[ents].name = name;
@@ -316,6 +349,8 @@ int cmd_diff(int argc, const char **argv, char **envp)
                        return builtin_diff_b_f(&rev, argc, argv, blob, path);
                        break;
                case 2:
+                       if (paths)
+                               usage(builtin_diff_usage);
                        return builtin_diff_blobs(&rev, argc, argv, blob);
                        break;
                default:
@@ -328,5 +363,7 @@ int cmd_diff(int argc, const char **argv, char **envp)
                return builtin_diff_index(&rev, argc, argv);
        else if (ents == 2)
                return builtin_diff_tree(&rev, argc, argv, ent);
+       else
+               return builtin_diff_combined(&rev, argc, argv, ent, ents);
        usage(builtin_diff_usage);
 }

diff --git a/combine-diff.c b/combine-diff.c
index ca36f5d..8a8fe38 100644 (file)
--- a/combine-diff.c
+++ b/combine-diff.c
@@ -831,15 +831,16 @@ void show_combined_diff(struct combine_diff_path *p,
        }
 }
 
-void diff_tree_combined_merge(const unsigned char *sha1,
-                            int dense, struct rev_info *rev)
+void diff_tree_combined(const unsigned char *sha1,
+                       const unsigned char parent[][20],
+                       int num_parent,
+                       int dense,
+                       struct rev_info *rev)
 {
        struct diff_options *opt = &rev->diffopt;
-       struct commit *commit = lookup_commit(sha1);
        struct diff_options diffopts;
-       struct commit_list *parents;
        struct combine_diff_path *p, *paths = NULL;
-       int num_parent, i, num_paths;
+       int i, num_paths;
        int do_diffstat;
 
        do_diffstat = (opt->output_format == DIFF_FORMAT_DIFFSTAT ||
@@ -849,17 +850,8 @@ void diff_tree_combined_merge(const unsigned char *sha1,
        diffopts.with_stat = 0;
        diffopts.recursive = 1;
 
-       /* count parents */
-       for (parents = commit->parents, num_parent = 0;
-            parents;
-            parents = parents->next, num_parent++)
-               ; /* nothing */
-
        /* find set of paths that everybody touches */
-       for (parents = commit->parents, i = 0;
-            parents;
-            parents = parents->next, i++) {
-               struct commit *parent = parents->item;
+       for (i = 0; i < num_parent; i++) {
                /* show stat against the first parent even
                 * when doing combined diff.
                 */
@@ -867,8 +859,7 @@ void diff_tree_combined_merge(const unsigned char *sha1,
                        diffopts.output_format = DIFF_FORMAT_DIFFSTAT;
                else
                        diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
-               diff_tree_sha1(parent->object.sha1, commit->object.sha1, "",
-                              &diffopts);
+               diff_tree_sha1(parent[i], sha1, "", &diffopts);
                diffcore_std(&diffopts);
                paths = intersect_paths(paths, i, num_parent);
 
@@ -907,3 +898,25 @@ void diff_tree_combined_merge(const unsigned char *sha1,
                free(tmp);
        }
 }
+
+void diff_tree_combined_merge(const unsigned char *sha1,
+                            int dense, struct rev_info *rev)
+{
+       int num_parent;
+       const unsigned char (*parent)[20];
+       struct commit *commit = lookup_commit(sha1);
+       struct commit_list *parents;
+
+       /* count parents */
+       for (parents = commit->parents, num_parent = 0;
+            parents;
+            parents = parents->next, num_parent++)
+               ; /* nothing */
+
+       parent = xmalloc(num_parent * sizeof(*parent));
+       for (parents = commit->parents, num_parent = 0;
+            parents;
+            parents = parents->next, num_parent++)
+               memcpy(parent + num_parent, parents->item->object.sha1, 20);
+       diff_tree_combined(sha1, parent, num_parent, dense, rev);
+}

diff --git a/diff.h b/diff.h
index 7150b90..b3b2c4d 100644 (file)
--- a/diff.h
+++ b/diff.h
@@ -75,6 +75,8 @@ struct combine_diff_path {
 extern void show_combined_diff(struct combine_diff_path *elem, int num_parent,
                              int dense, struct rev_info *);
 
+extern void diff_tree_combined(const unsigned char *sha1, const unsigned char parent[][20], int num_parent, int dense, struct rev_info *rev);
+
 extern void diff_tree_combined_merge(const unsigned char *sha1, int, struct rev_info *);
 
 extern void diff_addremove(struct diff_options *,

diff --git a/revision.c b/revision.c
index f2a9f25..4381d45 100644 (file)
--- a/revision.c
+++ b/revision.c
@@ -664,6 +664,7 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
                        }
                        if (!strcmp(arg, "-c")) {
                                revs->diff = 1;
+                               revs->dense_combined_merges = 0;
                                revs->combine_merges = 1;
                                continue;
                        }