test-grep: document that trivially moved lines might not be detected
I'm not going to fix this. I just learned "grep --diff" does clever thing
than a simple grep(patch.diff(context=0)), and I think it's better to
document how things work.
--- a/tests/test-grep.t Wed Sep 09 11:51:51 2020 +0900
+++ b/tests/test-grep.t Tue Sep 08 21:38:10 2020 +0900
@@ -640,6 +640,49 @@
$ cd ..
+Moved line may not be collected by "grep --diff" since it first filters
+the contents to be diffed by the pattern. (i.e.
+"diff <(grep pat a) <(grep pat b)", not "diff a b | grep pat".)
+This is much faster than generating full diff per revision.
+
+ $ hg init moved-line
+ $ cd moved-line
+ $ cat <<'EOF' > a
+ > foo
+ > bar
+ > baz
+ > EOF
+ $ hg ci -Am initial
+ adding a
+ $ cat <<'EOF' > a
+ > bar
+ > baz
+ > foo
+ > EOF
+ $ hg ci -m reorder
+
+ $ hg diff -c 1
+ diff -r a593cc55e81b -r 69789a3b6e80 a
+ --- a/a Thu Jan 01 00:00:00 1970 +0000
+ +++ b/a Thu Jan 01 00:00:00 1970 +0000
+ @@ -1,3 +1,3 @@
+ -foo
+ bar
+ baz
+ +foo
+
+ can't find the move of "foo" at the revision 1:
+
+ $ hg grep --diff foo -r1
+ [1]
+
+ "bar" isn't moved at the revisoin 1:
+
+ $ hg grep --diff bar -r1
+ [1]
+
+ $ cd ..
+
Test for showing working of allfiles flag
$ hg init sng