Bug 1369787 - [mozlint] Add a test for vcs operations, r=bc

Create a test for version control related functionality.

MozReview-Commit-ID: GXd27O69GNg

python/mozlint/test/test_vcs.py

@@ -0,0 +1,117 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import os
+import subprocess
+import sys
+
+import pytest
+
+from mozlint.vcs import VCSHelper, vcs_class
+
+
+setup = {
+    'hg': [
+        """
+        echo "foo" > foo
+        echo "bar" > bar
+        hg init
+        hg add *
+        hg commit -m "Initial commit"
+        """,
+        """
+        echo "[paths]\ndefault = ../remoterepo" > .hg/hgrc
+        """,
+        """
+        echo "bar" >> bar
+        echo "baz" > baz
+        hg add baz
+        hg rm foo
+        """,
+        """
+        hg commit -m "Remove foo; modify bar; add baz"
+        """,
+    ],
+    'git': [
+        """
+        echo "foo" > foo
+        echo "bar" > bar
+        git init
+        git add *
+        git commit -am "Initial commit"
+        """,
+        """
+        git remote add upstream ../remoterepo
+        git fetch upstream
+        git branch -u upstream/master
+        """,
+        """
+        echo "bar" >> bar
+        echo "baz" > baz
+        git add baz
+        git rm foo
+        """,
+        """
+        git commit -am "Remove foo; modify bar; add baz"
+        """
+    ]
+}
+
+
+def shell(cmd):
+    subprocess.check_call(cmd, shell=True)
+
+
+@pytest.yield_fixture(params=['git', 'hg'])
+def repo(tmpdir, request):
+    vcs = request.param
+
+    # tmpdir and repo are py.path objects
+    # http://py.readthedocs.io/en/latest/path.html
+    repo = tmpdir.mkdir('repo')
+    repo.vcs = vcs
+
+    # This creates a setup iterator. Each time next() is called
+    # on it, the next set of instructions will be executed.
+    repo.setup = (shell(cmd) for cmd in setup[vcs])
+
+    oldcwd = os.getcwd()
+    os.chdir(repo.strpath)
+
+    next(repo.setup)
+
+    repo.copy(tmpdir.join('remoterepo'))
+
+    next(repo.setup)
+
+    yield repo
+    os.chdir(oldcwd)
+
+
+def assert_files(actual, expected):
+    assert set(map(os.path.basename, actual)) == set(expected)
+
+
+def test_vcs_helper(repo):
+    vcs = VCSHelper.create()
+    assert vcs.__class__ == vcs_class[repo.vcs]
+    assert vcs.root == repo.strpath
+
+    remotepath = '../remoterepo' if repo.vcs == 'hg' else 'upstream/master'
+
+    next(repo.setup)
+
+    assert_files(vcs.by_workdir(), ['bar', 'baz'])
+    assert_files(vcs.by_outgoing(), [])
+    assert_files(vcs.by_outgoing(remotepath), [])
+
+    next(repo.setup)
+
+    assert_files(vcs.by_workdir(), [])
+    assert_files(vcs.by_outgoing(), ['bar', 'baz'])
+    assert_files(vcs.by_outgoing(remotepath), ['bar', 'baz'])
+
+
+if __name__ == '__main__':
+    sys.exit(pytest.main(['--verbose', __file__]))