[PATCH] tree-walk.c: fix overoptimistic inclusion in :(exclude) matching
- From
Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
- Date
- Nov 3, 2018, 15:30 UTC
- Message-ID
- <20181103153049.22850-1-pclouds@gmail.com>
- In-Reply-To
- <CAGOLd-5Gbt6fQTvm+7018uX+8WF7NUWpa1sFWAg3-5bxtmOt-Q@mail.gmail.com>
tree_entry_interesting() is used for matching pathspec on a tree. The interesting thing about this function is that, because the tree entries are known to be sorted, this function can return more than just "yes, matched" and "no, not matched". It can also say "yes, this entry is matched and so is the remaining entries in the tree".
This is where I made a mistake when matching exclude pathspec. For exclude pathspec, we do matching twice, one with positive patterns and one with negative ones, then a rule table is applied to determine the final "include or exclude" result. Note that "matched" does not necessarily mean include. For negative patterns, "matched" means exclude.
This particular rule is too eager to include everything. Rule 8 says that "if all entries are positively matched" and the current entry is not negatively matched (i.e. not excluded), then all entries are positively matched and therefore included. But this is not true. If the _current_ entry is not negatively matched, it does not mean the next one will not be and we cannot conclude right away that all remaining entries are positively matched and can be included.
Rules 8 and 18 are now updated to be less eager. We conclude that the current entry is positively matched and included. But we say nothing about remaining entries. tree_entry_interesting() will be called again for those entries where we will determine entries individually.
Reported-by: Christophe Bliard <christophe.bliard@trux.info> Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> --- t/t6132-pathspec-exclude.sh | 17 +++++++++++++++++ tree-walk.c | 11 ++++++++--- 2 files changed, 25 insertions(+), 3 deletions(-)
diff --git a/t/t6132-pathspec-exclude.sh b/t/t6132-pathspec-exclude.sh index eb829fce97..393b29f205 100755 --- a/t/t6132-pathspec-exclude.sh +++ b/t/t6132-pathspec-exclude.sh @@ -194,4 +194,21 @@ test_expect_success 'multiple exclusions' ' test_cmp expect actual ' +test_expect_success 't_e_i() exclude case #8' ' + git init case8 && + ( + cd case8 && + echo file >file1 && + echo file >file2 && + git add . && + git commit -m twofiles && + git grep -l file HEAD :^file2 >actual && + echo HEAD:file1 >expected && + test_cmp expected actual && + git grep -l file HEAD :^file1 >actual && + echo HEAD:file2 >expected && + test_cmp expected actual + ) +' + test_done diff --git a/tree-walk.c b/tree-walk.c index 77b37f36fa..79bafbd1a2 100644 --- a/tree-walk.c +++ b/tree-walk.c @@ -1107,7 +1107,7 @@ enum interesting tree_entry_interesting(const struct name_entry *entry, * 5 | file | 1 | 1 | 0 * 6 | file | 1 | 2 | 0 * 7 | file | 2 | -1 | 2 - * 8 | file | 2 | 0 | 2 + * 8 | file | 2 | 0 | 1 * 9 | file | 2 | 1 | 0 * 10 | file | 2 | 2 | -1 * -----+-------+----------+----------+------- @@ -1118,7 +1118,7 @@ enum interesting tree_entry_interesting(const struct name_entry *entry, * 15 | dir | 1 | 1 | 1 (*) * 16 | dir | 1 | 2 | 0 * 17 | dir | 2 | -1 | 2 - * 18 | dir | 2 | 0 | 2 + * 18 | dir | 2 | 0 | 1 * 19 | dir | 2 | 1 | 1 (*) * 20 | dir | 2 | 2 | -1 * @@ -1134,7 +1134,12 @@ enum interesting tree_entry_interesting(const struct name_entry *entry, negative = do_match(entry, base, base_offset, ps, 1); - /* #3, #4, #7, #8, #13, #14, #17, #18 */ + /* #8, #18 */ + if (positive == all_entries_interesting && + negative == entry_not_interesting) + return entry_interesting; + + /* #3, #4, #7, #13, #14, #17 */ if (negative <= entry_not_interesting) return positive;
-- 2.19.1.1005.gac84295441