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authorElijah Newren <newren@gmail.com>2018-04-19 17:58:19 (GMT)
committerJunio C Hamano <gitster@pobox.com>2018-05-08 07:11:00 (GMT)
commitc04ba51739a7771583e31966adb7c472980f3fc3 (patch)
tree44331e6956d5902832d430a1f99ca3411a1118ac /t/t6046-merge-skip-unneeded-updates.sh
parent2f682e21a6dc3b7403fd0162252183fdef019274 (diff)
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t6046: testcases checking whether updates can be skipped in a merge
Add several tests checking whether updates can be skipped in a merge. Also add several similar testcases for where updates cannot be skipped in a merge to make sure that we skip if and only if we should. In particular: * Testcase 1a (particularly 1a-check-L) would have pointed out the problem Linus has been dealing with for year with his merges[1]. * Testcase 2a (particularly 2a-check-L) would have pointed out the problem with my directory-rename-series before it broke master[2]. * Testcases 3[ab] (particularly 3a-check-L) provide a simpler testcase than 12b of t6043 making that one easier to understand. * There are several complementary testcases to make sure we're not just fixing those particular issues while regressing in the opposite direction. * There are also a pair of tests for the special case when a merge results in a skippable update AND the user has dirty modifications to the path. [1] https://public-inbox.org/git/CA+55aFzLZ3UkG5svqZwSnhNk75=fXJRkvU1m_RHBG54NOoaZPA@mail.gmail.com/ [2] https://public-inbox.org/git/xmqqmuya43cs.fsf@gitster-ct.c.googlers.com/ Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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diff --git a/t/t6046-merge-skip-unneeded-updates.sh b/t/t6046-merge-skip-unneeded-updates.sh
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+#!/bin/sh
+
+test_description="merge cases"
+
+# The setup for all of them, pictorially, is:
+#
+# A
+# o
+# / \
+# O o ?
+# \ /
+# o
+# B
+#
+# To help make it easier to follow the flow of tests, they have been
+# divided into sections and each test will start with a quick explanation
+# of what commits O, A, and B contain.
+#
+# Notation:
+# z/{b,c} means files z/b and z/c both exist
+# x/d_1 means file x/d exists with content d1. (Purpose of the
+# underscore notation is to differentiate different
+# files that might be renamed into each other's paths.)
+
+. ./test-lib.sh
+
+
+###########################################################################
+# SECTION 1: Cases involving no renames (one side has subset of changes of
+# the other side)
+###########################################################################
+
+# Testcase 1a, Changes on A, subset of changes on B
+# Commit O: b_1
+# Commit A: b_2
+# Commit B: b_3
+# Expected: b_2
+
+test_expect_success '1a-setup: Modify(A)/Modify(B), change on B subset of A' '
+ test_create_repo 1a &&
+ (
+ cd 1a &&
+
+ test_write_lines 1 2 3 4 5 6 7 8 9 10 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "O" &&
+
+ git branch O &&
+ git branch A &&
+ git branch B &&
+
+ git checkout A &&
+ test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 10.5 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "A" &&
+
+ git checkout B &&
+ test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "B"
+ )
+'
+
+test_expect_failure '1a-check-L: Modify(A)/Modify(B), change on B subset of A' '
+ test_when_finished "git -C 1a reset --hard" &&
+ test_when_finished "git -C 1a clean -fd" &&
+ (
+ cd 1a &&
+
+ git checkout A^0 &&
+
+ test-tool chmtime =31337 b &&
+ test-tool chmtime -v +0 b >expected-mtime &&
+
+ GIT_MERGE_VERBOSITY=3 git merge -s recursive B^0 >out 2>err &&
+
+ test_i18ngrep "Skipped b" out &&
+ test_must_be_empty err &&
+
+ test-tool chmtime -v +0 b >actual-mtime &&
+ test_cmp expected-mtime actual-mtime &&
+
+ git ls-files -s >index_files &&
+ test_line_count = 1 index_files &&
+
+ git rev-parse >actual HEAD:b &&
+ git rev-parse >expect A:b &&
+ test_cmp expect actual &&
+
+ git hash-object b >actual &&
+ git rev-parse A:b >expect &&
+ test_cmp expect actual
+ )
+'
+
+test_expect_success '1a-check-R: Modify(A)/Modify(B), change on B subset of A' '
+ test_when_finished "git -C 1a reset --hard" &&
+ test_when_finished "git -C 1a clean -fd" &&
+ (
+ cd 1a &&
+
+ git checkout B^0 &&
+
+ GIT_MERGE_VERBOSITY=3 git merge -s recursive A^0 >out 2>err &&
+
+ test_i18ngrep "Auto-merging b" out &&
+ test_must_be_empty err &&
+
+ git ls-files -s >index_files &&
+ test_line_count = 1 index_files &&
+
+ git rev-parse >actual HEAD:b &&
+ git rev-parse >expect A:b &&
+ test_cmp expect actual &&
+
+ git hash-object b >actual &&
+ git rev-parse A:b >expect &&
+ test_cmp expect actual
+ )
+'
+
+
+###########################################################################
+# SECTION 2: Cases involving basic renames
+###########################################################################
+
+# Testcase 2a, Changes on A, rename on B
+# Commit O: b_1
+# Commit A: b_2
+# Commit B: c_1
+# Expected: c_2
+
+test_expect_success '2a-setup: Modify(A)/rename(B)' '
+ test_create_repo 2a &&
+ (
+ cd 2a &&
+
+ test_seq 1 10 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "O" &&
+
+ git branch O &&
+ git branch A &&
+ git branch B &&
+
+ git checkout A &&
+ test_seq 1 11 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "A" &&
+
+ git checkout B &&
+ git mv b c &&
+ test_tick &&
+ git commit -m "B"
+ )
+'
+
+test_expect_failure '2a-check-L: Modify/rename, merge into modify side' '
+ test_when_finished "git -C 2a reset --hard" &&
+ test_when_finished "git -C 2a clean -fd" &&
+ (
+ cd 2a &&
+
+ git checkout A^0 &&
+
+ GIT_MERGE_VERBOSITY=3 git merge -s recursive B^0 >out 2>err &&
+
+ test_i18ngrep ! "Skipped c" out &&
+ test_must_be_empty err &&
+
+ git ls-files -s >index_files &&
+ test_line_count = 1 index_files &&
+
+ git rev-parse >actual HEAD:c &&
+ git rev-parse >expect A:b &&
+ test_cmp expect actual &&
+
+ git hash-object c >actual &&
+ git rev-parse A:b >expect &&
+ test_cmp expect actual &&
+
+ test_must_fail git rev-parse HEAD:b &&
+ test_path_is_missing b
+ )
+'
+
+test_expect_success '2a-check-R: Modify/rename, merge into rename side' '
+ test_when_finished "git -C 2a reset --hard" &&
+ test_when_finished "git -C 2a clean -fd" &&
+ (
+ cd 2a &&
+
+ git checkout B^0 &&
+
+ GIT_MERGE_VERBOSITY=3 git merge -s recursive A^0 >out 2>err &&
+
+ test_i18ngrep ! "Skipped c" out &&
+ test_must_be_empty err &&
+
+ git ls-files -s >index_files &&
+ test_line_count = 1 index_files &&
+
+ git rev-parse >actual HEAD:c &&
+ git rev-parse >expect A:b &&
+ test_cmp expect actual &&
+
+ git hash-object c >actual &&
+ git rev-parse A:b >expect &&
+ test_cmp expect actual &&
+
+ test_must_fail git rev-parse HEAD:b &&
+ test_path_is_missing b
+ )
+'
+
+# Testcase 2b, Changed and renamed on A, subset of changes on B
+# Commit O: b_1
+# Commit A: c_2
+# Commit B: b_3
+# Expected: c_2
+
+test_expect_success '2b-setup: Rename+Mod(A)/Mod(B), B mods subset of A' '
+ test_create_repo 2b &&
+ (
+ cd 2b &&
+
+ test_write_lines 1 2 3 4 5 6 7 8 9 10 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "O" &&
+
+ git branch O &&
+ git branch A &&
+ git branch B &&
+
+ git checkout A &&
+ test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 10.5 >b &&
+ git add b &&
+ git mv b c &&
+ test_tick &&
+ git commit -m "A" &&
+
+ git checkout B &&
+ test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "B"
+ )
+'
+
+test_expect_success '2b-check-L: Rename+Mod(A)/Mod(B), B mods subset of A' '
+ test_when_finished "git -C 2b reset --hard" &&
+ test_when_finished "git -C 2b clean -fd" &&
+ (
+ cd 2b &&
+
+ git checkout A^0 &&
+
+ test-tool chmtime =31337 c &&
+ test-tool chmtime -v +0 c >expected-mtime &&
+
+ GIT_MERGE_VERBOSITY=3 git merge -s recursive B^0 >out 2>err &&
+
+ test_i18ngrep "Skipped c" out &&
+ test_must_be_empty err &&
+
+ test-tool chmtime -v +0 c >actual-mtime &&
+ test_cmp expected-mtime actual-mtime &&
+
+ git ls-files -s >index_files &&
+ test_line_count = 1 index_files &&
+
+ git rev-parse >actual HEAD:c &&
+ git rev-parse >expect A:c &&
+ test_cmp expect actual &&
+
+ git hash-object c >actual &&
+ git rev-parse A:c >expect &&
+ test_cmp expect actual &&
+
+ test_must_fail git rev-parse HEAD:b &&
+ test_path_is_missing b
+ )
+'
+
+test_expect_success '2b-check-R: Rename+Mod(A)/Mod(B), B mods subset of A' '
+ test_when_finished "git -C 2b reset --hard" &&
+ test_when_finished "git -C 2b clean -fd" &&
+ (
+ cd 2b &&
+
+ git checkout B^0 &&
+
+ GIT_MERGE_VERBOSITY=3 git merge -s recursive A^0 >out 2>err &&
+
+ test_i18ngrep "Auto-merging c" out &&
+ test_must_be_empty err &&
+
+ git ls-files -s >index_files &&
+ test_line_count = 1 index_files &&
+
+ git rev-parse >actual HEAD:c &&
+ git rev-parse >expect A:c &&
+ test_cmp expect actual &&
+
+ git hash-object c >actual &&
+ git rev-parse A:c >expect &&
+ test_cmp expect actual &&
+
+ test_must_fail git rev-parse HEAD:b &&
+ test_path_is_missing b
+ )
+'
+
+# Testcase 2c, Changes on A, rename on B
+# Commit O: b_1
+# Commit A: b_2, c_3
+# Commit B: c_1
+# Expected: rename/add conflict c_2 vs c_3
+#
+# NOTE: Since A modified b_1->b_2, and B renamed b_1->c_1, the threeway
+# merge of those files should result in c_2. We then should have a
+# rename/add conflict between c_2 and c_3. However, if we note in
+# merge_content() that A had the right contents (b_2 has same
+# contents as c_2, just at a different name), and that A had the
+# right path present (c_3 existed) and thus decides that it can
+# skip the update, then we're in trouble. This test verifies we do
+# not make that particular mistake.
+
+test_expect_success '2c-setup: Modify b & add c VS rename b->c' '
+ test_create_repo 2c &&
+ (
+ cd 2c &&
+
+ test_seq 1 10 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "O" &&
+
+ git branch O &&
+ git branch A &&
+ git branch B &&
+
+ git checkout A &&
+ test_seq 1 11 >b &&
+ echo whatever >c &&
+ git add b c &&
+ test_tick &&
+ git commit -m "A" &&
+
+ git checkout B &&
+ git mv b c &&
+ test_tick &&
+ git commit -m "B"
+ )
+'
+
+test_expect_failure '2c-check: Modify b & add c VS rename b->c' '
+ (
+ cd 2c &&
+
+ git checkout A^0 &&
+
+ GIT_MERGE_VERBOSITY=3 test_must_fail git merge -s recursive B^0 >out 2>err &&
+
+ test_i18ngrep "CONFLICT (rename/add): Rename b->c" out &&
+ test_i18ngrep ! "Skipped c" out &&
+ test_must_be_empty err
+
+ # FIXME: rename/add conflicts are horribly broken right now;
+ # when I get back to my patch series fixing it and
+ # rename/rename(2to1) conflicts to bring them in line with
+ # how add/add conflicts behave, then checks like the below
+ # could be added. But that patch series is waiting until
+ # the rename-directory-detection series lands, which this
+ # is part of. And in the mean time, I do not want to further
+ # enforce broken behavior. So for now, the main test is the
+ # one above that err is an empty file.
+
+ #git ls-files -s >index_files &&
+ #test_line_count = 2 index_files &&
+
+ #git rev-parse >actual :2:c :3:c &&
+ #git rev-parse >expect A:b A:c &&
+ #test_cmp expect actual &&
+
+ #git cat-file -p A:b >>merged &&
+ #git cat-file -p A:c >>merge-me &&
+ #>empty &&
+ #test_must_fail git merge-file \
+ # -L "Temporary merge branch 1" \
+ # -L "" \
+ # -L "Temporary merge branch 2" \
+ # merged empty merge-me &&
+ #sed -e "s/^\([<=>]\)/\1\1\1/" merged >merged-internal &&
+
+ #git hash-object c >actual &&
+ #git hash-object merged-internal >expect &&
+ #test_cmp expect actual &&
+
+ #test_path_is_missing b
+ )
+'
+
+
+###########################################################################
+# SECTION 3: Cases involving directory renames
+#
+# NOTE:
+# Directory renames only apply when one side renames a directory, and the
+# other side adds or renames a path into that directory. Applying the
+# directory rename to that new path creates a new pathname that didn't
+# exist on either side of history. Thus, it is impossible for the
+# merge contents to already be at the right path, so all of these checks
+# exist just to make sure that updates are not skipped.
+###########################################################################
+
+# Testcase 3a, Change + rename into dir foo on A, dir rename foo->bar on B
+# Commit O: bq_1, foo/whatever
+# Commit A: foo/{bq_2, whatever}
+# Commit B: bq_1, bar/whatever
+# Expected: bar/{bq_2, whatever}
+
+test_expect_success '3a-setup: bq_1->foo/bq_2 on A, foo/->bar/ on B' '
+ test_create_repo 3a &&
+ (
+ cd 3a &&
+
+ mkdir foo &&
+ test_seq 1 10 >bq &&
+ test_write_lines a b c d e f g h i j k >foo/whatever &&
+ git add bq foo/whatever &&
+ test_tick &&
+ git commit -m "O" &&
+
+ git branch O &&
+ git branch A &&
+ git branch B &&
+
+ git checkout A &&
+ test_seq 1 11 >bq &&
+ git add bq &&
+ git mv bq foo/ &&
+ test_tick &&
+ git commit -m "A" &&
+
+ git checkout B &&
+ git mv foo/ bar/ &&
+ test_tick &&
+ git commit -m "B"
+ )
+'
+
+test_expect_failure '3a-check-L: bq_1->foo/bq_2 on A, foo/->bar/ on B' '
+ test_when_finished "git -C 3a reset --hard" &&
+ test_when_finished "git -C 3a clean -fd" &&
+ (
+ cd 3a &&
+
+ git checkout A^0 &&
+
+ GIT_MERGE_VERBOSITY=3 git merge -s recursive B^0 >out 2>err &&
+
+ test_i18ngrep ! "Skipped bar/bq" out &&
+ test_must_be_empty err &&
+
+ git ls-files -s >index_files &&
+ test_line_count = 2 index_files &&
+
+ git rev-parse >actual HEAD:bar/bq HEAD:bar/whatever &&
+ git rev-parse >expect A:foo/bq A:foo/whatever &&
+ test_cmp expect actual &&
+
+ git hash-object bar/bq bar/whatever >actual &&
+ git rev-parse A:foo/bq A:foo/whatever >expect &&
+ test_cmp expect actual &&
+
+ test_must_fail git rev-parse HEAD:bq HEAD:foo/bq &&
+ test_path_is_missing bq foo/bq foo/whatever
+ )
+'
+
+test_expect_success '3a-check-R: bq_1->foo/bq_2 on A, foo/->bar/ on B' '
+ test_when_finished "git -C 3a reset --hard" &&
+ test_when_finished "git -C 3a clean -fd" &&
+ (
+ cd 3a &&
+
+ git checkout B^0 &&
+
+ GIT_MERGE_VERBOSITY=3 git merge -s recursive A^0 >out 2>err &&
+
+ test_i18ngrep ! "Skipped bar/bq" out &&
+ test_must_be_empty err &&
+
+ git ls-files -s >index_files &&
+ test_line_count = 2 index_files &&
+
+ git rev-parse >actual HEAD:bar/bq HEAD:bar/whatever &&
+ git rev-parse >expect A:foo/bq A:foo/whatever &&
+ test_cmp expect actual &&
+
+ git hash-object bar/bq bar/whatever >actual &&
+ git rev-parse A:foo/bq A:foo/whatever >expect &&
+ test_cmp expect actual &&
+
+ test_must_fail git rev-parse HEAD:bq HEAD:foo/bq &&
+ test_path_is_missing bq foo/bq foo/whatever
+ )
+'
+
+# Testcase 3b, rename into dir foo on A, dir rename foo->bar + change on B
+# Commit O: bq_1, foo/whatever
+# Commit A: foo/{bq_1, whatever}
+# Commit B: bq_2, bar/whatever
+# Expected: bar/{bq_2, whatever}
+
+test_expect_success '3b-setup: bq_1->foo/bq_2 on A, foo/->bar/ on B' '
+ test_create_repo 3b &&
+ (
+ cd 3b &&
+
+ mkdir foo &&
+ test_seq 1 10 >bq &&
+ test_write_lines a b c d e f g h i j k >foo/whatever &&
+ git add bq foo/whatever &&
+ test_tick &&
+ git commit -m "O" &&
+
+ git branch O &&
+ git branch A &&
+ git branch B &&
+
+ git checkout A &&
+ git mv bq foo/ &&
+ test_tick &&
+ git commit -m "A" &&
+
+ git checkout B &&
+ test_seq 1 11 >bq &&
+ git add bq &&
+ git mv foo/ bar/ &&
+ test_tick &&
+ git commit -m "B"
+ )
+'
+
+test_expect_success '3b-check-L: bq_1->foo/bq_2 on A, foo/->bar/ on B' '
+ test_when_finished "git -C 3b reset --hard" &&
+ test_when_finished "git -C 3b clean -fd" &&
+ (
+ cd 3b &&
+
+ git checkout A^0 &&
+
+ GIT_MERGE_VERBOSITY=3 git merge -s recursive B^0 >out 2>err &&
+
+ test_i18ngrep ! "Skipped bar/bq" out &&
+ test_must_be_empty err &&
+
+ git ls-files -s >index_files &&
+ test_line_count = 2 index_files &&
+
+ git rev-parse >actual HEAD:bar/bq HEAD:bar/whatever &&
+ git rev-parse >expect B:bq A:foo/whatever &&
+ test_cmp expect actual &&
+
+ git hash-object bar/bq bar/whatever >actual &&
+ git rev-parse B:bq A:foo/whatever >expect &&
+ test_cmp expect actual &&
+
+ test_must_fail git rev-parse HEAD:bq HEAD:foo/bq &&
+ test_path_is_missing bq foo/bq foo/whatever
+ )
+'
+
+test_expect_failure '3b-check-R: bq_1->foo/bq_2 on A, foo/->bar/ on B' '
+ test_when_finished "git -C 3b reset --hard" &&
+ test_when_finished "git -C 3b clean -fd" &&
+ (
+ cd 3b &&
+
+ git checkout B^0 &&
+
+ GIT_MERGE_VERBOSITY=3 git merge -s recursive A^0 >out 2>err &&
+
+ test_i18ngrep ! "Skipped bar/bq" out &&
+ test_must_be_empty err &&
+
+ git ls-files -s >index_files &&
+ test_line_count = 2 index_files &&
+
+ git rev-parse >actual HEAD:bar/bq HEAD:bar/whatever &&
+ git rev-parse >expect B:bq A:foo/whatever &&
+ test_cmp expect actual &&
+
+ git hash-object bar/bq bar/whatever >actual &&
+ git rev-parse B:bq A:foo/whatever >expect &&
+ test_cmp expect actual &&
+
+ test_must_fail git rev-parse HEAD:bq HEAD:foo/bq &&
+ test_path_is_missing bq foo/bq foo/whatever
+ )
+'
+
+###########################################################################
+# SECTION 4: Cases involving dirty changes
+###########################################################################
+
+# Testcase 4a, Changed on A, subset of changes on B, locally modified
+# Commit O: b_1
+# Commit A: b_2
+# Commit B: b_3
+# Working copy: b_4
+# Expected: b_2 for merge, b_4 in working copy
+
+test_expect_success '4a-setup: Change on A, change on B subset of A, dirty mods present' '
+ test_create_repo 4a &&
+ (
+ cd 4a &&
+
+ test_write_lines 1 2 3 4 5 6 7 8 9 10 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "O" &&
+
+ git branch O &&
+ git branch A &&
+ git branch B &&
+
+ git checkout A &&
+ test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 10.5 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "A" &&
+
+ git checkout B &&
+ test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "B"
+ )
+'
+
+# NOTE: For as long as we continue using unpack_trees() without index_only
+# set to true, it will error out on a case like this claiming the the locally
+# modified file would be overwritten by the merge. Getting this testcase
+# correct requires doing the merge in-memory first, then realizing that no
+# updates to the file are necessary, and thus that we can just leave the path
+# alone.
+test_expect_failure '4a-check: Change on A, change on B subset of A, dirty mods present' '
+ test_when_finished "git -C 4a reset --hard" &&
+ test_when_finished "git -C 4a clean -fd" &&
+ (
+ cd 4a &&
+
+ git checkout A^0 &&
+ echo "File rewritten" >b &&
+
+ test-tool chmtime =31337 b &&
+ test-tool chmtime -v +0 b >expected-mtime &&
+
+ GIT_MERGE_VERBOSITY=3 git merge -s recursive B^0 >out 2>err &&
+
+ test_i18ngrep "Skipped b" out &&
+ test_must_be_empty err &&
+
+ test-tool chmtime -v +0 b >actual-mtime &&
+ test_cmp expected-mtime actual-mtime &&
+
+ git ls-files -s >index_files &&
+ test_line_count = 1 index_files &&
+
+ git rev-parse >actual :0:b &&
+ git rev-parse >expect A:b &&
+ test_cmp expect actual &&
+
+ git hash-object b >actual &&
+ echo "File rewritten" | git hash-object --stdin >expect &&
+ test_cmp expect actual
+ )
+'
+
+# Testcase 4b, Changed+renamed on A, subset of changes on B, locally modified
+# Commit O: b_1
+# Commit A: c_2
+# Commit B: b_3
+# Working copy: c_4
+# Expected: c_2
+
+test_expect_success '4b-setup: Rename+Mod(A)/Mod(B), change on B subset of A, dirty mods present' '
+ test_create_repo 4b &&
+ (
+ cd 4b &&
+
+ test_write_lines 1 2 3 4 5 6 7 8 9 10 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "O" &&
+
+ git branch O &&
+ git branch A &&
+ git branch B &&
+
+ git checkout A &&
+ test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 10.5 >b &&
+ git add b &&
+ git mv b c &&
+ test_tick &&
+ git commit -m "A" &&
+
+ git checkout B &&
+ test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 >b &&
+ git add b &&
+ test_tick &&
+ git commit -m "B"
+ )
+'
+
+test_expect_success '4b-check: Rename+Mod(A)/Mod(B), change on B subset of A, dirty mods present' '
+ test_when_finished "git -C 4b reset --hard" &&
+ test_when_finished "git -C 4b clean -fd" &&
+ (
+ cd 4b &&
+
+ git checkout A^0 &&
+ echo "File rewritten" >c &&
+
+ test-tool chmtime =31337 c &&
+ test-tool chmtime -v +0 c >expected-mtime &&
+
+ GIT_MERGE_VERBOSITY=3 git merge -s recursive B^0 >out 2>err &&
+
+ test_i18ngrep "Skipped c" out &&
+ test_must_be_empty err &&
+
+ test-tool chmtime -v +0 c >actual-mtime &&
+ test_cmp expected-mtime actual-mtime &&
+
+ git ls-files -s >index_files &&
+ test_line_count = 1 index_files &&
+
+ git rev-parse >actual :0:c &&
+ git rev-parse >expect A:c &&
+ test_cmp expect actual &&
+
+ git hash-object c >actual &&
+ echo "File rewritten" | git hash-object --stdin >expect &&
+ test_cmp expect actual &&
+
+ test_must_fail git rev-parse HEAD:b &&
+ test_path_is_missing b
+ )
+'
+
+test_done