From 35ffe7583108ab236dcf81226690388491d9962f Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Thu, 13 Dec 2012 15:51:29 -0800 Subject: [PATCH] merge-tree: fix d/f conflicts The previous commit documented two known breakages revolving around a case where one side flips a tree into a blob (or vice versa), where the original code simply gets confused and feeds a mixture of trees and blobs into either the recursive merge-tree (and recursing into the blob will fail) or three-way merge (and merging tree contents together with blobs will fail). Fix it by feeding trees (and only trees) into the recursive merge-tree machinery and blobs (and only blobs) into the three-way content level merge machinery separately; when this happens, the entire merge has to be marked as conflicting at the structure level. Signed-off-by: Junio C Hamano --- builtin/merge-tree.c | 72 ++++++++++++++++++++++++++++----------------------- t/t4300-merge-tree.sh | 4 +-- 2 files changed, 42 insertions(+), 34 deletions(-) diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c index 5704d51050..e0d0b7d28b 100644 --- a/builtin/merge-tree.c +++ b/builtin/merge-tree.c @@ -25,7 +25,7 @@ static void add_merge_entry(struct merge_list *entry) merge_result_end = &entry->next; } -static void merge_trees(struct tree_desc t[3], const char *base); +static void merge_trees_recursive(struct tree_desc t[3], const char *base, int df_conflict); static const char *explanation(struct merge_list *entry) { @@ -190,41 +190,35 @@ static void resolve(const struct traverse_info *info, struct name_entry *ours, s add_merge_entry(final); } -static int unresolved_directory(const struct traverse_info *info, struct name_entry n[3]) +static void unresolved_directory(const struct traverse_info *info, struct name_entry n[3], + int df_conflict) { char *newbase; struct name_entry *p; struct tree_desc t[3]; void *buf0, *buf1, *buf2; - p = n; - if (!p->mode) { - p++; - if (!p->mode) - p++; + for (p = n; p < n + 3; p++) { + if (p->mode && S_ISDIR(p->mode)) + break; } - if (!S_ISDIR(p->mode)) - return 0; - /* - * NEEDSWORK: this is broken. The path can originally be a file - * and then one side may have turned it into a directory, in which - * case we return and let the three-way merge as if the tree were - * a regular file. If the path that was originally a tree is - * now a file in either branch, fill_tree_descriptor() below will - * die when fed a blob sha1. - */ + if (n + 3 <= p) + return; /* there is no tree here */ newbase = traverse_path(info, p); - buf0 = fill_tree_descriptor(t+0, n[0].sha1); - buf1 = fill_tree_descriptor(t+1, n[1].sha1); - buf2 = fill_tree_descriptor(t+2, n[2].sha1); - merge_trees(t, newbase); + +#define ENTRY_SHA1(e) (((e)->mode && S_ISDIR((e)->mode)) ? (e)->sha1 : NULL) + buf0 = fill_tree_descriptor(t+0, ENTRY_SHA1(n + 0)); + buf1 = fill_tree_descriptor(t+1, ENTRY_SHA1(n + 1)); + buf2 = fill_tree_descriptor(t+2, ENTRY_SHA1(n + 2)); +#undef ENTRY_SHA1 + + merge_trees_recursive(t, newbase, df_conflict); free(buf0); free(buf1); free(buf2); free(newbase); - return 1; } @@ -247,18 +241,26 @@ static struct merge_list *link_entry(unsigned stage, const struct traverse_info static void unresolved(const struct traverse_info *info, struct name_entry n[3]) { struct merge_list *entry = NULL; + int i; + unsigned dirmask = 0, mask = 0; + + for (i = 0; i < 3; i++) { + mask |= (1 << 1); + if (n[i].mode && S_ISDIR(n[i].mode)) + dirmask |= (1 << i); + } + + unresolved_directory(info, n, dirmask && (dirmask != mask)); - if (unresolved_directory(info, n)) + if (dirmask == mask) return; - /* - * Do them in reverse order so that the resulting link - * list has the stages in order - link_entry adds new - * links at the front. - */ - entry = link_entry(3, info, n + 2, entry); - entry = link_entry(2, info, n + 1, entry); - entry = link_entry(1, info, n + 0, entry); + if (n[2].mode && !S_ISDIR(n[2].mode)) + entry = link_entry(3, info, n + 2, entry); + if (n[1].mode && !S_ISDIR(n[1].mode)) + entry = link_entry(2, info, n + 1, entry); + if (n[0].mode && !S_ISDIR(n[0].mode)) + entry = link_entry(1, info, n + 0, entry); add_merge_entry(entry); } @@ -329,15 +331,21 @@ static int threeway_callback(int n, unsigned long mask, unsigned long dirmask, s return mask; } -static void merge_trees(struct tree_desc t[3], const char *base) +static void merge_trees_recursive(struct tree_desc t[3], const char *base, int df_conflict) { struct traverse_info info; setup_traverse_info(&info, base); + info.data = &df_conflict; info.fn = threeway_callback; traverse_trees(3, t, &info); } +static void merge_trees(struct tree_desc t[3], const char *base) +{ + merge_trees_recursive(t, base, 0); +} + static void *get_tree_descriptor(struct tree_desc *desc, const char *rev) { unsigned char sha1[20]; diff --git a/t/t4300-merge-tree.sh b/t/t4300-merge-tree.sh index 03e8fcad35..d0b2a457b8 100755 --- a/t/t4300-merge-tree.sh +++ b/t/t4300-merge-tree.sh @@ -254,7 +254,7 @@ EXPECTED test_cmp expected actual ' -test_expect_failure 'turn file to tree' ' +test_expect_success 'turn file to tree' ' git reset --hard initial && rm initial-file && mkdir initial-file && @@ -274,7 +274,7 @@ test_expect_failure 'turn file to tree' ' test_cmp expect actual ' -test_expect_failure 'turn tree to file' ' +test_expect_success 'turn tree to file' ' git reset --hard initial && mkdir dir && test_commit "add-tree" "dir/path" "AAA" && -- 2.11.4.GIT