sapling/scripts/unit.py

#!/usr/bin/env python

"""run a subset of tests that related to the current change

Optionally write result using JSON format. The JSON format can be parsed
by MercurialTestEngine.php
"""

import json
import optparse
import os
import re
import subprocess
import sys

sys.path.insert(0, os.path.dirname(__file__))
import utils

reporoot = utils.reporoot

def info(message):
    """print message to stderr"""
    sys.stderr.write(message)

def checkoutput(*args, **kwds):
    """like subprocess.checked_output, but raise RuntimeError and return
    stderr as a second value.
    """
    proc = subprocess.Popen(*args, stdout=subprocess.PIPE,
                            stderr=subprocess.PIPE, **kwds)
    out, err = proc.communicate()
    retcode = proc.poll()
    if retcode:
        raise RuntimeError('%r exits with %d' % (args, retcode))
    return out, err

def changedfiles(rev='wdir() + .'):
    """return a list of paths (relative to repo root) that rev touches.
    by default, check the working directory and its parent.
    """
    cmd = ['hg', 'log', '-T', '{join(files,"\\0")}\\0', '-r', rev]
    out, err = checkoutput(cmd, cwd=reporoot)
    return set(out.rstrip('\0').split('\0'))

def words(path):
    """strip extension and split it to words.
    for example, 'a/b-c.txt' -> ['a', 'b', 'c']
    """
    return re.split('[^\w]+', os.path.splitext(path)[0])

def interestingtests(changed_files):
    """return a list of interesting test filenames"""
    tests = [p for p in os.listdir(os.path.join(reporoot, 'tests'))
             if p.startswith('test-') and p[-2:] in ['py', '.t']]

    result = set()

    # Build a dictionary mapping words to the relevant tests
    # (tests whose name contains that word)
    testwords = {}
    for t in tests:
        # Include all tests starting with test-check*,
        if t.startswith('test-check'):
            result.add(t)
            continue

        for word in words(t)[1:]:
            test_set = testwords.setdefault(word, set())
            test_set.add(t)

    # A test is interesting if there is a common word in both the path of the
    # changed source file and the name of the test file. For example:
    # - test-githelp.t is interesting if githelp.py is changed
    # - test-remotefilelog-sparse.t is interesting if sparse.py is changed
    # - test-remotefilelog-foo.t is interesting if remotefilelog/* is changed
    for path in changed_files:
        if path.startswith('tests/test-'):
            # for a test file, do not enable other tests but only itself
            result.add(os.path.basename(path))
            continue
        for w in words(path):
            result.update(testwords.get(w, []))

    return result

def runtests(tests=None):
    """run given tests

    Returns a tuple of (exitcode, report)
    exitcode will be 0 on success, and non-zero on failure
    report is a dictionary of test results.
    """
    args = ['-l', '--json']
    if tests:
        args += tests

    # Run the tests.
    #
    # We ignore KeyboardInterrupt while running the tests: when the user hits
    # Ctrl-C the interrupt will also be delivered to the test runner, which
    # should cause it to exit soon.  We want to wait for the test runner to
    # exit before we quit.  Otherwise may keep printing data even after we have
    # exited and returned control of the terminal to the user's shell.
    proc = utils.spawnruntests(args)
    interruptcount = 0
    maxinterrupts = 3
    while True:
        try:
            exitcode = proc.wait()
            break
        except KeyboardInterrupt:
            interruptcount += 1
            if interruptcount >= maxinterrupts:
                sys.stderr.write('Warning: test runner has not exited after '
                                 'multiple interrupts.  Giving up on it and '
                                 'quiting anyway.\n')
                raise

    try:
        reportpath = os.path.join(reporoot, 'tests', 'report.json')
        with open(reportpath) as rf:
            report_contents = rf.read()

        # strip the "testreport =" header which makes the JSON illegal
        report = json.loads(re.sub('^testreport =', '', report_contents))
        os.unlink(reportpath)
    except (EnvironmentError, ValueError) as ex:
        # If anything goes wrong parsing the report.json file, build our own
        # fake failure report, and make sure we have non-zero exit code.
        sys.stderr.write('warning: error reading results: %s\n' % (ex,))
        report = {'run-tests': {'result': 'failure'}}
        if exitcode == 0:
            exitcode = 1

    return exitcode, report

def main():
    op = optparse.OptionParser()
    op.add_option('-j', '--json',
                  metavar='FILE',
                  help='Write a JSON result file at the specified location')
    opts, args = op.parse_args()

    if args:
        changed_files = args
    else:
        changed_files = changedfiles()

    tests = interestingtests(changed_files)
    if tests:
        info('%d test%s to run: %s\n'
             % (len(tests), ('' if len(tests) == 1 else 's'), ' '.join(tests)))
        exitcode, report = runtests(tests)
    else:
        info('no tests to run\n')
        exitcode = 0
        report = {}

    if opts.json:
        with open(opts.json, 'w') as fp:
            json.dump(report, fp)
    return exitcode

if __name__ == '__main__':
    exitcode = main()
    sys.exit(exitcode)