[PATCH] Teach diff-tree to honor grafts
From: Junio C Hamano <hidden>
Date: 2016-06-15 22:42:13
Subsystem:
the rest · Maintainer:
Linus Torvalds
Junio C Hamano [off-list ref] writes:
Santi Béjar [off-list ref] writes:quoted
diff-tree decode directly the commit, so it does not take into account the graft file. Is this the expected behaviour?Expected? Yes, only because I happen to know diff-tree was written way before grafts are invented and nobody bothered to change that behaviour. Desireable? Probably not.
Something like this (only lightly tested) should make it work in one-tree case. The --stdin form does not necessarily need this if you tell rev-list to show the parents, but that case should be covered as well with this patch. -- >8 -- "git-rev-list --parent" piped to "git-diff-tree --stdin" honors grafts because rev-list will explicitly tell diff-tree what base commit to compare each commit against, but a single parameter "git-diff-tree oneEnt" form did its own thing to extract parent information from the commit object by hand, without honoring the grafts the user has. Rewrite that part to use parse_commit() API. ---
diff --git a/diff-tree.c b/diff-tree.c
index 09d16ad..e79a134 100644
--- a/diff-tree.c
+++ b/diff-tree.c@@ -69,52 +69,50 @@ static int diff_root_tree(const unsigned return retval; } -static const char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len) +static const char *generate_header(const char *commit, const char *parent, const char *msg) { static char this_header[16384]; int offset; + unsigned long len; if (!verbose_header) return commit; + len = strlen(msg); offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent); offset += pretty_print_commit(commit_format, msg, len, this_header + offset, sizeof(this_header) - offset); return this_header; } -static int diff_tree_commit(const unsigned char *commit, const char *name) +static int diff_tree_commit(const unsigned char *commit_sha1) { - unsigned long size, offset; - char *buf = read_object_with_reference(commit, "commit", &size, NULL); + struct commit *commit; + struct commit_list *parents; + char name[50]; + unsigned char sha1[20]; - if (!buf) + sprintf(name, "%s^0", sha1_to_hex(commit_sha1)); + if (get_sha1(name, sha1)) return -1; - - if (!name) { - static char commit_name[60]; - strcpy(commit_name, sha1_to_hex(commit)); - name = commit_name; - } - + name[40] = 0; + commit = lookup_commit(sha1); + /* Root commit? */ - if (show_root_diff && memcmp(buf + 46, "parent ", 7)) { - header = generate_header(name, "root", buf, size); - diff_root_tree(commit, ""); + if (show_root_diff && !commit->parents) { + header = generate_header(name, "root", commit->buffer); + diff_root_tree(commit_sha1, ""); } /* More than one parent? */ - if (ignore_merges) { - if (!memcmp(buf + 46 + 48, "parent ", 7)) + if (ignore_merges && commit->parents && commit->parents->next) return 0; - } - offset = 46; - while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) { - unsigned char parent[20]; - if (get_sha1_hex(buf + offset + 7, parent)) - return -1; - header = generate_header(name, sha1_to_hex(parent), buf, size); - diff_tree_sha1_top(parent, commit, ""); + for (parents = commit->parents; parents; parents = parents->next) { + struct commit *parent = parents->item; + header = generate_header(name, + sha1_to_hex(parent->object.sha1), + commit->buffer); + diff_tree_sha1_top(parent->object.sha1, commit_sha1, ""); if (!header && verbose_header) { header_prefix = "\ndiff-tree "; /*
@@ -122,9 +120,7 @@ static int diff_tree_commit(const unsign * don't print the diffs. */ } - offset += 48; } - free(buf); return 0; }
@@ -147,7 +143,7 @@ static int diff_tree_stdin(char *line) return diff_tree_sha1_top(parent, commit, ""); } line[40] = 0; - return diff_tree_commit(commit, line); + return diff_tree_commit(commit); } static const char diff_tree_usage[] =
@@ -250,7 +246,7 @@ int main(int argc, const char **argv) usage(diff_tree_usage); break; case 1: - diff_tree_commit(sha1[0], NULL); + diff_tree_commit(sha1[0]); break; case 2: diff_tree_sha1_top(sha1[0], sha1[1], "");