tests/pdiff

resourceutil: force filesystem access to resources when using py2exe

I don't know why it doesn't work, but it avoids this fatal error on startup:

    > hg debugshell
    Traceback (most recent call last):
      File "hg", line 58, in <module>
      File "mercurial\dispatch.pyc", line 143, in run
      File "mercurial\dispatch.pyc", line 232, in dispatch
      File "mercurial\dispatch.pyc", line 254, in _rundispatch
      File "mercurial\ui.pyc", line 316, in load
      File "mercurial\rcutil.pyc", line 98, in rccomponents
      File "mercurial\rcutil.pyc", line 68, in default_rc_resources
      File "mercurial\utils\resourceutil.pyc", line 102, in contents
      File "<frozen zipimport>", line 775, in contents
    AssertionError

I assume the py2 version of py2exe never hit this because `importlib.resources`
failed to import.

Differential Revision: https://phab.mercurial-scm.org/D12554

#!/bin/sh

# Script to get stable diff output on any platform.
#
# Output of this script is almost equivalent to GNU diff with "-Nru".
#
# Use this script as "hg pdiff" via extdiff extension with preparation
# below in test scripts:
#
#   $ cat >> $HGRCPATH <<EOF
#   > [extdiff]
#   > pdiff = sh "$RUNTESTDIR/pdiff"
#   > EOF

filediff(){
    # USAGE: filediff file1 file2 [header]

    # compare with /dev/null if file doesn't exist (as "-N" option)
    file1="$1"
    if test ! -f "$file1"; then
        file1=/dev/null
    fi
    file2="$2"
    if test ! -f "$file2"; then
        file2=/dev/null
    fi

    if cmp -s "$file1" "$file2" 2> /dev/null; then
        # Return immediately, because comparison isn't needed. This
        # also avoids redundant message of diff like "No differences
        # encountered" (on Solaris)
        return
    fi

    if test -n "$3"; then
        # show header only in recursive case
        echo "$3"
    fi

    # replace "/dev/null" by corresponded filename (as "-N" option)
    diff -u "$file1" "$file2" |
    sed "s@^--- /dev/null\(.*\)\$@--- $1\1@" |
    sed "s@^\+\+\+ /dev/null\(.*\)\$@+++ $2\1@"

    # in this case, files differ from each other
    return 1
}

if test -d "$1" -o -d "$2"; then
    # ensure comparison in dictionary order
    (
    if test -d "$1"; then (cd "$1" && find . -type f); fi
    if test -d "$2"; then (cd "$2" && find . -type f); fi
    ) |
    sed 's@^\./@@g' | sort | uniq |
    while read file; do
        filediff "$1/$file" "$2/$file" "diff -Nru $1/$file $2/$file"
    done

    # TODO: there is no portable way for current while-read based
    # implementation to return 1 at detecting changes.
    #
    # On bash and dash, assignment to variable inside while-block
    # doesn't affect outside, because inside while-block is executed
    # in sub-shell. BTW, it affects outside while-block on ksh (as sh
    # on Solaris).
else
    filediff "$1" "$2"
fi