t7063: mtime-mangling instead of delays in untracked cache testing

The untracked cache test uses an avoid_racy function to deal with
an mtime-resolution challenge in testing: If an untracked cache
entry's mtime falls in the same second as the mtime of the index
the untracked cache was stored in, then it cannot be trusted.

Explicitly delaying tests is a simple effective strategy to
avoid these issues, but should be avoided where possible.

Switch from a delay-based strategy to instead backdating
all file changes using test-tool chmtime, where that is an
option, to shave 9 seconds off the test run time.

Don't update test cases that delay for other reasons, for now at
least (4 seconds).

Signed-off-by: Tao Klerks <tao@klerks.biz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/t/t7063-status-untracked-cache.sh b/t/t7063-status-untracked-cache.sh
index a0c123b0a77a6f99877d4e5cd2fd74cb78e0b96c..ca90ee805e7b3411c6e7c8c5868c3aa2063dba05 100755 (executable)
--- a/t/t7063-status-untracked-cache.sh
+++ b/t/t7063-status-untracked-cache.sh
@@ -90,6 +90,9 @@ test_expect_success 'setup' '
        cd worktree &&
        mkdir done dtwo dthree &&
        touch one two three done/one dtwo/two dthree/three &&
+       test-tool chmtime =-300 one two three done/one dtwo/two dthree/three &&
+       test-tool chmtime =-300 done dtwo dthree &&
+       test-tool chmtime =-300 . &&
        git add one two done/one &&
        : >.git/info/exclude &&
        git update-index --untracked-cache &&
@@ -142,7 +145,6 @@ two
 EOF
 
 test_expect_success 'status first time (empty cache)' '
-       avoid_racy &&
        : >../trace.output &&
        GIT_TRACE2_PERF="$TRASH_DIRECTORY/trace.output" \
        git status --porcelain >../actual &&
@@ -166,7 +168,6 @@ test_expect_success 'untracked cache after first status' '
 '
 
 test_expect_success 'status second time (fully populated cache)' '
-       avoid_racy &&
        : >../trace.output &&
        GIT_TRACE2_PERF="$TRASH_DIRECTORY/trace.output" \
        git status --porcelain >../actual &&
@@ -190,8 +191,8 @@ test_expect_success 'untracked cache after second status' '
 '
 
 test_expect_success 'modify in root directory, one dir invalidation' '
-       avoid_racy &&
        : >four &&
+       test-tool chmtime =-240 four &&
        : >../trace.output &&
        GIT_TRACE2_PERF="$TRASH_DIRECTORY/trace.output" \
        git status --porcelain >../actual &&
@@ -241,7 +242,6 @@ EOF
 '
 
 test_expect_success 'new .gitignore invalidates recursively' '
-       avoid_racy &&
        echo four >.gitignore &&
        : >../trace.output &&
        GIT_TRACE2_PERF="$TRASH_DIRECTORY/trace.output" \
@@ -292,7 +292,6 @@ EOF
 '
 
 test_expect_success 'new info/exclude invalidates everything' '
-       avoid_racy &&
        echo three >>.git/info/exclude &&
        : >../trace.output &&
        GIT_TRACE2_PERF="$TRASH_DIRECTORY/trace.output" \
@@ -520,14 +519,14 @@ test_expect_success 'create/modify files, some of which are gitignored' '
        echo three >done/three && # three is gitignored
        echo four >done/four && # four is gitignored at a higher level
        echo five >done/five && # five is not gitignored
-       echo test >base && #we need to ensure that the root dir is touched
-       rm base &&
+       test-tool chmtime =-180 done/two done/three done/four done/five done &&
+       # we need to ensure that the root dir is touched (in the past);
+       test-tool chmtime =-180 . &&
        sync_mtime
 '
 
 test_expect_success 'test sparse status with untracked cache' '
        : >../trace.output &&
-       avoid_racy &&
        GIT_TRACE2_PERF="$TRASH_DIRECTORY/trace.output" \
        git status --porcelain >../status.actual &&
        iuc status --porcelain >../status.iuc &&
@@ -570,7 +569,6 @@ EOF
 '
 
 test_expect_success 'test sparse status again with untracked cache' '
-       avoid_racy &&
        : >../trace.output &&
        GIT_TRACE2_PERF="$TRASH_DIRECTORY/trace.output" \
        git status --porcelain >../status.actual &&
@@ -597,11 +595,11 @@ EOF
 test_expect_success 'set up for test of subdir and sparse checkouts' '
        mkdir done/sub &&
        mkdir done/sub/sub &&
-       echo "sub" > done/sub/sub/file
+       echo "sub" > done/sub/sub/file &&
+       test-tool chmtime =-120 done/sub/sub/file done/sub/sub done/sub done
 '
 
 test_expect_success 'test sparse status with untracked cache and subdir' '
-       avoid_racy &&
        : >../trace.output &&
        GIT_TRACE2_PERF="$TRASH_DIRECTORY/trace.output" \
        git status --porcelain >../status.actual &&
@@ -651,7 +649,6 @@ EOF
 '
 
 test_expect_success 'test sparse status again with untracked cache and subdir' '
-       avoid_racy &&
        : >../trace.output &&
        GIT_TRACE2_PERF="$TRASH_DIRECTORY/trace.output" \
        git status --porcelain >../status.actual &&