Many tests didn't change back from subdirectories at the end of the tests ...
and they don't have to. The missing 'cd ..' could always be added when another
test case is added to the test file.
This change do that tests (99.5%) consistently end up in $TESTDIR where they
started, thus making it simpler to extend them or move them around.
When diffing the following documents with --ignore-blank-lines (-B):
$ cat > a <<EOF
>
>
>
> b
> x
> d
> EOF
and:
$ cat > b <<EOF
> b
> y
> d
> EOF
the context lines are taken from the first document, even if the lines differ
(with -w or -b) or if the number of lines differ (with -B). In the second case,
we have to adjust the hunk new lines offsets or we end with inconsistent diffs
like (see the @@ offsets):
diff -r 0e66aa54f318 a
--- a/a
+++ b/a
@@ -1,4 +1,3 @@
b
-x
+y
d
Note that having different context lines in a and b means the diff can be
applied but is not invertible.
Reported by Nicholas Riley <com-selenic@sabi.net>
If a file is deleted (rm, not 'hg rm') from the working dir
an attempt to run 'hg diff -r X', with the file being present in X will
cause an abort.
We didn't check if the file has been deleted from the working dir
and later on tried to open it to compare with the one from X, causing the abort.
This fix adds that check. Consequently, no output will be returned.
