view tests/pdiff @ 51833:6388fd855f66 stable

setup: handle removal of old MSVC compiler from setuptools 65.0 (issue6910)

It was removed a few years ago[1].  When trying to reproduce locally using a
clean py3.12 as called out in the bug report, `setuptools` wasn't installed at
all, and needed a `pip install` to fix a `ModuleNotFoundError` when building
locally.  Maybe that needs to be in the requirements clause now.

It looks like this "private" module was added in setuptools 48.0.[2]  I can't
find a changelog of what version was included in which version of python, and
the changelog for pip has a huge gap between when it called out 67.6.1 in `pip`
23.1 (2023-04-15), and 41.4.0 in `pip` 19.3 (2019-10-14).[3]  So, we'll just add
to the existing code instead of replacing it, for safety.

[1] https://github.com/pypa/setuptools/commit/cc017c77948737d131f683e0c25cd37bc639b8fc
[2] https://github.com/pypa/setuptools/commit/d034a5ec7f707499139f90eb846b9e720923124c
[3] https://pip.pypa.io/en/stable/news/

#!/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