tests: add test for Python 3 compatibility
Python 3 is inevitable. There have been incremental movements towards
converting the code base to be Python 3 compatible. Unfortunately, we
don't have any tests that look for Python 3 compatibility. This patch
changes that.
We introduce a check-py3-compat.py script whose role is to verify
Python 3 compatibility of the files passed in. We add a test that
calls this script with all .py files from the source checkout.
The script currently only verifies that absolute_import and
print_function are used. These are the low hanging fruits for Python
compatbility. Over time, we can include more checks, including
verifying we're able to load each Python file with Python 3. You
have to start somewhere.
Accepting this patch means that all new .py files must have
absolute_import and print_function (if "print" is used) to avoid
a new warning about Python 3 incompatibility. We've already
converted several files to use absolute_import and print_function
is in the same boat, so I don't think this is such a radical
proposition.
$ cat <<EOF > merge
> import sys, os
> print "merging for", os.path.basename(sys.argv[1])
> EOF
$ HGMERGE="python ../merge"; export HGMERGE
$ hg init A1
$ cd A1
$ echo This is file foo1 > foo
$ echo This is file bar1 > bar
$ hg add foo bar
$ hg commit -m "commit text"
$ cd ..
$ hg clone A1 B1
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd A1
$ rm bar
$ hg remove bar
$ hg commit -m "commit test"
$ cd ../B1
$ echo This is file foo22 > foo
$ hg commit -m "commit test"
$ cd ..
$ hg clone A1 A2
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg clone B1 B2
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd A1
$ hg pull ../B1
pulling from ../B1
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg merge
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m "commit test"
bar should remain deleted.
$ hg manifest --debug
f9b0e817f6a48de3564c6b2957687c5e7297c5a0 644 foo
$ cd ../B2
$ hg pull ../A2
pulling from ../A2
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 0 changes to 0 files (+1 heads)
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg merge
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m "commit test"
bar should remain deleted.
$ hg manifest --debug
f9b0e817f6a48de3564c6b2957687c5e7297c5a0 644 foo
$ cd ..