templates: add filter to reverse list
The filter supports only lists because for lists, it’s straightforward to
implement. Reversing text doesn’t seem very useful and is hard to implement.
Reversing the bytes would break multi-bytes encodings. Reversing the code
points would break characters consisting of multiple code points. Reversing
graphemes is non-trivial without using a library not included in the standard
library.
A script that implements uppercasing all letters in a file.
$ UPPERCASEPY="$TESTTMP/uppercase.py"
$ cat > $UPPERCASEPY <<EOF
> import sys
> from mercurial.utils.procutil import setbinary
> setbinary(sys.stdin)
> setbinary(sys.stdout)
> sys.stdout.write(sys.stdin.read().upper())
> EOF
$ TESTLINES="foo\nbar\nbaz\n"
$ printf $TESTLINES | "$PYTHON" $UPPERCASEPY
FOO
BAR
BAZ
This file attempts to test our workarounds for pickle's lack of
support for short reads.
$ cat >> $HGRCPATH <<EOF
> [extensions]
> fix =
> [fix]
> uppercase-whole-file:command="$PYTHON" $UPPERCASEPY
> uppercase-whole-file:pattern=set:**
> EOF
$ hg init repo
$ cd repo
# Create a file that's large enough that it seems to not fit in
# pickle's buffer, making it use the code path that expects our
# _blockingreader's read() method to return bytes.
$ echo "some stuff" > file
$ for i in $($TESTDIR/seq.py 13); do
> cat file file > tmp
> mv -f tmp file
> done
$ hg commit -Am "add large file"
adding file
Check that we don't get a crash
$ hg fix -r .
saved backup bundle to $TESTTMP/repo/.hg/strip-backup/*-fix.hg (glob)