diff options
| -rw-r--r-- | diffcore-rename.c | 73 |
1 files changed, 63 insertions, 10 deletions
diff --git a/diffcore-rename.c b/diffcore-rename.c index 0a17abd466..8fa29076e0 100644 --- a/diffcore-rename.c +++ b/diffcore-rename.c @@ -407,6 +407,28 @@ static const char *get_highest_rename_path(struct strintmap *counts) return highest_destination_dir; } +static char *UNKNOWN_DIR = "/"; /* placeholder -- short, illegal directory */ + +static int dir_rename_already_determinable(struct strintmap *counts) +{ + struct hashmap_iter iter; + struct strmap_entry *entry; + int first = 0, second = 0, unknown = 0; + strintmap_for_each_entry(counts, &iter, entry) { + const char *destination_dir = entry->key; + intptr_t count = (intptr_t)entry->value; + if (!strcmp(destination_dir, UNKNOWN_DIR)) { + unknown = count; + } else if (count >= first) { + second = first; + first = count; + } else if (count >= second) { + second = count; + } + } + return first > second + unknown; +} + static void increment_count(struct dir_rename_info *info, char *old_dir, char *new_dir) @@ -1096,17 +1118,48 @@ static void handle_early_known_dir_renames(struct dir_rename_info *info, struct strintmap *dirs_removed) { /* - * Not yet implemented; directory renames are determined via an - * aggregate of all renames under them and using a "majority wins" - * rule. The fact that "majority wins", though, means we don't need - * all the renames under the given directory, we only need enough to - * ensure we have a majority. - * - * For now, we don't have enough information to know if we have a - * majority after exact renames and basename-guided rename detection, - * so just return early without doing any extra filtering. + * Directory renames are determined via an aggregate of all renames + * under them and using a "majority wins" rule. The fact that + * "majority wins", though, means we don't need all the renames + * under the given directory, we only need enough to ensure we have + * a majority. */ - return; + + struct hashmap_iter iter; + struct strmap_entry *entry; + + if (!dirs_removed || !relevant_sources) + return; /* nothing to cull */ + if (break_idx) + return; /* culling incompatbile with break detection */ + + /* + * FIXME: Supplement dir_rename_count with number of potential + * renames, marking all potential rename sources as mapping to + * UNKNOWN_DIR. + */ + + /* + * For any directory which we need a potential rename detected for + * (i.e. those marked as RELEVANT_FOR_SELF in dirs_removed), check + * whether we have enough renames to satisfy the "majority rules" + * requirement such that detecting any more renames of files under + * it won't change the result. For any such directory, mark that + * we no longer need to detect a rename for it. However, since we + * might need to still detect renames for an ancestor of that + * directory, use RELEVANT_FOR_ANCESTOR. + */ + strmap_for_each_entry(info->dir_rename_count, &iter, entry) { + /* entry->key is source_dir */ + struct strintmap *counts = entry->value; + + if (strintmap_get(dirs_removed, entry->key) == + RELEVANT_FOR_SELF && + dir_rename_already_determinable(counts)) { + strintmap_set(dirs_removed, entry->key, + RELEVANT_FOR_ANCESTOR); + } + } } void diffcore_rename_extended(struct diff_options *options, |