Merge branch 'sg/diff-multiple-identical-renames' into maint

"git diff -M" used to work better when two originally identical
files A and B got renamed to X/A and X/B by pairing A to X/A and B
to X/B, but this was broken in the 2.0 timeframe.

* sg/diff-multiple-identical-renames:
diffcore: fix iteration order of identical files during rename detection

diff --git a/diffcore-rename.c b/diffcore-rename.c
index 3b3c1ed535e7c8b17947d69dbe0bd5c8f115cf2d..7f03eb5a0404d4b44f292fba76433dfec74dcd44 100644 (file)
--- a/diffcore-rename.c
+++ b/diffcore-rename.c
@@ -340,9 +340,11 @@ static int find_exact_renames(struct diff_options *options)
        int i, renames = 0;
        struct hashmap file_table;
 
-       /* Add all sources to the hash table */
+       /* Add all sources to the hash table in reverse order, because
+        * later on they will be retrieved in LIFO order.
+        */
        hashmap_init(&file_table, NULL, rename_src_nr);
-       for (i = 0; i < rename_src_nr; i++)
+       for (i = rename_src_nr-1; i >= 0; i--)
                insert_file_table(&file_table, i, rename_src[i].p->one);
 
        /* Walk the destinations and find best source match */

diff --git a/t/t4001-diff-rename.sh b/t/t4001-diff-rename.sh
index 2f327b749588af7eda57187cba4d365233a25ef9..ed90c6c6f984979bfc250d277486550cb5129e30 100755 (executable)
--- a/t/t4001-diff-rename.sh
+++ b/t/t4001-diff-rename.sh
@@ -77,6 +77,17 @@ test_expect_success 'favour same basenames even with minor differences' '
        git show HEAD:path1 | sed "s/15/16/" > subdir/path1 &&
        git status | test_i18ngrep "renamed: .*path1 -> subdir/path1"'
 
+test_expect_success 'two files with same basename and same content' '
+       git reset --hard &&
+       mkdir -p dir/A dir/B &&
+       cp path1 dir/A/file &&
+       cp path1 dir/B/file &&
+       git add dir &&
+       git commit -m 2 &&
+       git mv dir other-dir &&
+       git status | test_i18ngrep "renamed: .*dir/A/file -> other-dir/A/file"
+'
+
 test_expect_success 'setup for many rename source candidates' '
        git reset --hard &&
        for i in 0 1 2 3 4 5 6 7 8 9;