@@ -70,10 +70,7 @@ additional rules:
a) If renames split a directory into two or more others, the directory
with the most renames, "wins".
- b) Avoid directory-rename-detection for a path, if that path is the
- source of a rename on either side of a merge.
-
- c) Only apply implicit directory renames to directories if the other side
+ b) Only apply implicit directory renames to directories if the other side
of history is the one doing the renaming.
Limitations -- support in different commands
@@ -1277,20 +1277,114 @@ test_expect_success '6a: Tricky rename/delete' '
)
'
-# Testcase 6b, Same rename done on both sides
+# Testcase 6b1, Same rename done on both sides
+# (Related to testcase 6b2 and 8e)
+# Commit O: z/{b,c,d,e}
+# Commit A: y/{b,c,d}, x/e
+# Commit B: y/{b,c,d}, z/{e,f}
+# Expected: y/{b,c,d,f}, x/e
+# Note: Directory rename detection says A renamed z/ -> y/ (3 paths renamed
+# to y/ and only 1 renamed to x/), therefore the new file 'z/f' in B
+# should be moved to 'y/f'.
+#
+# This is a bit of an edge case where any behavior might surprise users,
+# whether that is treating A as renaming z/ -> y/, treating A as renaming
+# z/ -> x/, or treating A as not doing any directory rename. However, I
+# think this answer is the least confusing and most consistent with the
+# rules elsewhere.
+#
+# A note about z/ -> x/, since it may not be clear how that could come
+# about: If we were to ignore files renamed by both sides
+# (i.e. z/{b,c,d}), as directory rename detection did in git-2.18 thru
+# at least git-2.28, then we would note there are no renames from z/ to
+# y/ and one rename from z/ to x/ and thus come to the conclusion that
+# A renamed z/ -> x/. This seems more confusing for end users than a
+# rename of z/ to y/, it makes directory rename detection behavior
+# harder for them to predict. As such, we modified the rule, changed
+# the behavior on testcases 6b2 and 8e, and introduced this 6b1 testcase.
+
+test_setup_6b1 () {
+ test_create_repo 6b1 &&
+ (
+ cd 6b1 &&
+
+ mkdir z &&
+ echo b >z/b &&
+ echo c >z/c &&
+ echo d >z/d &&
+ echo e >z/e &&
+ git add z &&
+ test_tick &&
+ git commit -m "O" &&
+
+ git branch O &&
+ git branch A &&
+ git branch B &&
+
+ git checkout A &&
+ git mv z y &&
+ mkdir x &&
+ git mv y/e x/e &&
+ test_tick &&
+ git commit -m "A" &&
+
+ git checkout B &&
+ git mv z y &&
+ mkdir z &&
+ git mv y/e z/e &&
+ echo f >z/f &&
+ git add z/f &&
+ test_tick &&
+ git commit -m "B"
+ )
+}
+
+test_expect_failure '6b1: Same renames done on both sides, plus another rename' '
+ test_setup_6b1 &&
+ (
+ cd 6b1 &&
+
+ git checkout A^0 &&
+
+ git -c merge.directoryRenames=true merge -s recursive B^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 5 out &&
+ git ls-files -u >out &&
+ test_line_count = 0 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >actual \
+ HEAD:y/b HEAD:y/c HEAD:y/d HEAD:x/e HEAD:y/f &&
+ git rev-parse >expect \
+ O:z/b O:z/c O:z/d O:z/e B:z/f &&
+ test_cmp expect actual
+ )
+'
+
+# Testcase 6b2, Same rename done on both sides
# (Related to testcases 6c and 8e)
# Commit O: z/{b,c}
# Commit A: y/{b,c}
# Commit B: y/{b,c}, z/d
-# Expected: y/{b,c}, z/d
-# Note: If we did directory rename detection here, we'd move z/d into y/,
-# but B did that rename and still decided to put the file into z/,
-# so we probably shouldn't apply directory rename detection for it.
-
-test_setup_6b () {
- test_create_repo 6b &&
+# Expected: y/{b,c,d}
+# Alternate: y/{b,c}, z/d
+# Note: Directory rename detection says A renamed z/ -> y/, therefore the new
+# file 'z/d' in B should be moved to 'y/d'.
+#
+# We could potentially ignore the renames of z/{b,c} on side A since
+# those were renamed on both sides. However, it's a bit of a corner
+# case because what if there was also a z/e that side A moved to x/e
+# and side B left alone? If we used the "ignore renames done on both
+# sides" logic, then we'd compute that A renamed z/ -> x/, and move
+# z/d to x/d. That seems more surprising and uglier than allowing
+# the z/ -> y/ rename.
+
+test_setup_6b2 () {
+ test_create_repo 6b2 &&
(
- cd 6b &&
+ cd 6b2 &&
mkdir z &&
echo b >z/b &&
@@ -1318,10 +1412,10 @@ test_setup_6b () {
)
}
-test_expect_success '6b: Same rename done on both sides' '
- test_setup_6b &&
+test_expect_failure '6b2: Same rename done on both sides' '
+ test_setup_6b2 &&
(
- cd 6b &&
+ cd 6b2 &&
git checkout A^0 &&
@@ -1335,7 +1429,7 @@ test_expect_success '6b: Same rename done on both sides' '
test_line_count = 1 out &&
git rev-parse >actual \
- HEAD:y/b HEAD:y/c HEAD:z/d &&
+ HEAD:y/b HEAD:y/c HEAD:y/d &&
git rev-parse >expect \
O:z/b O:z/c B:z/d &&
test_cmp expect actual
@@ -1343,7 +1437,7 @@ test_expect_success '6b: Same rename done on both sides' '
'
# Testcase 6c, Rename only done on same side
-# (Related to testcases 6b and 8e)
+# (Related to testcases 6b1, 6b2, and 8e)
# Commit O: z/{b,c}
# Commit A: z/{b,c} (no change)
# Commit B: y/{b,c}, z/d
@@ -2269,14 +2363,22 @@ test_expect_success '8d: rename/delete...or not?' '
# Notes: In commit A, directory z got renamed to y. In commit B, directory z
# did NOT get renamed; the directory is still present; instead it is
# considered to have just renamed a subset of paths in directory z
-# elsewhere. However, this is much like testcase 6b (where commit B
-# moves all the original paths out of z/ but opted to keep d
-# within z/). This makes it hard to judge where d should end up.
+# elsewhere. This is much like testcase 6b2 (where commit B moves all
+# the original paths out of z/ but opted to keep d within z/).
+#
+# It was not clear in the past what should be done with this testcase;
+# in fact, I noted that I "just picked one" previously. However,
+# following the new logic for testcase 6b2, we should take the rename
+# and move z/d to y/d.
#
-# It's possible that users would get confused about this, but what
-# should we do instead? It's not at all clear to me whether z/d or
-# y/d or something else is a better resolution here, and other cases
-# start getting really tricky, so I just picked one.
+# 6b1, 6b2, and this case are definitely somewhat fuzzy in terms of
+# whether they are optimal for end users, but (a) the default for
+# directory rename detection is to mark these all as conflicts
+# anyway, (b) it feels like this is less prone to higher order corner
+# case confusion, and (c) the current algorithm requires less global
+# knowledge (i.e. less coupling in the algorithm between renames done
+# on both sides) which thus means users are better able to predict
+# the behavior, and predict it without computing as many details.
test_setup_8e () {
test_create_repo 8e &&