init: respect --repo-rev changes

We respect this option when running the first `repo init`, but then
silently ignore it once the initial sync is done.  Make sure users
are able to change things on the fly.

We refactor the wrapper API to allow reuse between the two init's.

Bug: https://crbug.com/gerrit/11045
Change-Id: Icb89a8cddca32f39a760a6283152457810b2392d
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/260032
Tested-by: Mike Frysinger <vapier@google.com>
Reviewed-by: Jonathan Nieder <jrn@google.com>

3 files changed, 195 insertions, 22 deletions

diff --git a/repo b/repo
index c78fcacd..66a2a07d 100755
--- a/repo
+++ b/repo
@@ -463,6 +463,34 @@ class CloneFailure(Exception):
   """
 
 
+def check_repo_verify(repo_verify, quiet=False):
+  """Check the --repo-verify state."""
+  if not repo_verify:
+    print('repo: warning: verification of repo code has been disabled;\n'
+          'repo will not be able to verify the integrity of itself.\n',
+          file=sys.stderr)
+    return False
+
+  if NeedSetupGnuPG():
+    return SetupGnuPG(quiet)
+
+  return True
+
+
+def check_repo_rev(dst, rev, repo_verify=True, quiet=False):
+  """Check that |rev| is valid."""
+  do_verify = check_repo_verify(repo_verify, quiet=quiet)
+  remote_ref, local_rev = resolve_repo_rev(dst, rev)
+  if not quiet and not remote_ref.startswith('refs/heads/'):
+    print('warning: repo is not tracking a remote branch, so it will not '
+          'receive updates', file=sys.stderr)
+  if do_verify:
+    rev = verify_rev(dst, remote_ref, local_rev, quiet)
+  else:
+    rev = local_rev
+  return (remote_ref, rev)
+
+
 def _Init(args, gitc_init=False):
   """Installs repo by cloning it over the network.
   """
@@ -510,30 +538,12 @@ def _Init(args, gitc_init=False):
 
   _CheckGitVersion()
   try:
-    if not opt.repo_verify:
-      do_verify = False
-      print('repo: warning: verification of repo code has been disabled;\n'
-            'repo will not be able to verify the integrity of itself.\n',
-            file=sys.stderr)
-    else:
-      if NeedSetupGnuPG():
-        do_verify = SetupGnuPG(opt.quiet)
-      else:
-        do_verify = True
-
     if not opt.quiet:
       print('Downloading Repo source from', url)
     dst = os.path.abspath(os.path.join(repodir, S_repo))
     _Clone(url, dst, opt.clone_bundle, opt.quiet, opt.verbose)
 
-    remote_ref, local_rev = resolve_repo_rev(dst, rev)
-    if not opt.quiet and not remote_ref.startswith('refs/heads/'):
-      print('warning: repo is not tracking a remote branch, so it will not '
-            'receive updates', file=sys.stderr)
-    if do_verify:
-      rev = _Verify(dst, remote_ref, local_rev, opt.quiet)
-    else:
-      rev = local_rev
+    remote_ref, rev = check_repo_rev(dst, rev, opt.repo_verify, quiet=opt.quiet)
     _Checkout(dst, remote_ref, rev, opt.quiet)
 
     if not os.path.isfile(os.path.join(dst, 'repo')):
@@ -907,7 +917,7 @@ def resolve_repo_rev(cwd, committish):
   raise CloneFailure()
 
 
-def _Verify(cwd, remote_ref, rev, quiet):
+def verify_rev(cwd, remote_ref, rev, quiet):
   """Verify the commit has been signed by a tag."""
   ret = run_git('describe', rev, cwd=cwd)
   cur = ret.stdout.strip()
diff --git a/subcmds/init.py b/subcmds/init.py
index 431165d4..ce8b0187 100644
--- a/subcmds/init.py
+++ b/subcmds/init.py
@@ -38,6 +38,7 @@ from project import SyncBuffer
 from git_config import GitConfig
 from git_command import git_require, MIN_GIT_VERSION_SOFT, MIN_GIT_VERSION_HARD
 import platform_utils
+from wrapper import Wrapper
 
 
 class Init(InteractiveCommand, MirrorSafeCommand):
@@ -499,6 +500,16 @@ to update the working directory files.
       remote.url = opt.repo_url
       remote.Save()
 
+    # Handle new --repo-rev requests.
+    if opt.repo_rev:
+      wrapper = Wrapper()
+      remote_ref, rev = wrapper.check_repo_rev(
+          rp.gitdir, opt.repo_rev, repo_verify=opt.repo_verify, quiet=opt.quiet)
+      branch = rp.GetBranch('default')
+      branch.merge = remote_ref
+      rp.work_git.update_ref('refs/heads/default', rev)
+      branch.Save()
+
     if opt.worktree:
       # Older versions of git supported worktree, but had dangerous gc bugs.
       git_require((2, 15, 0), fail=True, msg='git gc worktree corruption')
diff --git a/tests/test_wrapper.py b/tests/test_wrapper.py
index 73c62cc1..136f7f11 100644
--- a/tests/test_wrapper.py
+++ b/tests/test_wrapper.py
@@ -18,12 +18,14 @@
 
 from __future__ import print_function
 
+import contextlib
 import os
 import re
 import shutil
 import tempfile
 import unittest
 
+import platform_utils
 from pyversion import is_python3
 import wrapper
 
@@ -36,6 +38,18 @@ else:
   from StringIO import StringIO
 
 
+@contextlib.contextmanager
+def TemporaryDirectory():
+  """Create a new empty git checkout for testing."""
+  # TODO(vapier): Convert this to tempfile.TemporaryDirectory once we drop
+  # Python 2 support entirely.
+  try:
+    tempdir = tempfile.mkdtemp(prefix='repo-tests')
+    yield tempdir
+  finally:
+    platform_utils.rmtree(tempdir)
+
+
 def fixture(*paths):
   """Return a path relative to tests/fixtures.
   """
@@ -243,8 +257,93 @@ class CheckGitVersion(RepoWrapperTestCase):
       self.wrapper._CheckGitVersion()
 
 
-class ResolveRepoRev(RepoWrapperTestCase):
-  """Check resolve_repo_rev behavior."""
+class NeedSetupGnuPG(RepoWrapperTestCase):
+  """Check NeedSetupGnuPG behavior."""
+
+  def test_missing_dir(self):
+    """The ~/.repoconfig tree doesn't exist yet."""
+    with TemporaryDirectory() as tempdir:
+      self.wrapper.home_dot_repo = os.path.join(tempdir, 'foo')
+      self.assertTrue(self.wrapper.NeedSetupGnuPG())
+
+  def test_missing_keyring(self):
+    """The keyring-version file doesn't exist yet."""
+    with TemporaryDirectory() as tempdir:
+      self.wrapper.home_dot_repo = tempdir
+      self.assertTrue(self.wrapper.NeedSetupGnuPG())
+
+  def test_empty_keyring(self):
+    """The keyring-version file exists, but is empty."""
+    with TemporaryDirectory() as tempdir:
+      self.wrapper.home_dot_repo = tempdir
+      with open(os.path.join(tempdir, 'keyring-version'), 'w'):
+        pass
+      self.assertTrue(self.wrapper.NeedSetupGnuPG())
+
+  def test_old_keyring(self):
+    """The keyring-version file exists, but it's old."""
+    with TemporaryDirectory() as tempdir:
+      self.wrapper.home_dot_repo = tempdir
+      with open(os.path.join(tempdir, 'keyring-version'), 'w') as fp:
+        fp.write('1.0\n')
+      self.assertTrue(self.wrapper.NeedSetupGnuPG())
+
+  def test_new_keyring(self):
+    """The keyring-version file exists, and is up-to-date."""
+    with TemporaryDirectory() as tempdir:
+      self.wrapper.home_dot_repo = tempdir
+      with open(os.path.join(tempdir, 'keyring-version'), 'w') as fp:
+        fp.write('1000.0\n')
+      self.assertFalse(self.wrapper.NeedSetupGnuPG())
+
+
+class SetupGnuPG(RepoWrapperTestCase):
+  """Check SetupGnuPG behavior."""
+
+  def test_full(self):
+    """Make sure it works completely."""
+    with TemporaryDirectory() as tempdir:
+      self.wrapper.home_dot_repo = tempdir
+      self.assertTrue(self.wrapper.SetupGnuPG(True))
+      with open(os.path.join(tempdir, 'keyring-version'), 'r') as fp:
+        data = fp.read()
+      self.assertEqual('.'.join(str(x) for x in self.wrapper.KEYRING_VERSION),
+                       data.strip())
+
+
+class VerifyRev(RepoWrapperTestCase):
+  """Check verify_rev behavior."""
+
+  def test_verify_passes(self):
+    """Check when we have a valid signed tag."""
+    desc_result = self.wrapper.RunResult(0, 'v1.0\n', '')
+    gpg_result = self.wrapper.RunResult(0, '', '')
+    with mock.patch.object(self.wrapper, 'run_git',
+                           side_effect=(desc_result, gpg_result)):
+      ret = self.wrapper.verify_rev('/', 'refs/heads/stable', '1234', True)
+      self.assertEqual('v1.0^0', ret)
+
+  def test_unsigned_commit(self):
+    """Check we fall back to signed tag when we have an unsigned commit."""
+    desc_result = self.wrapper.RunResult(0, 'v1.0-10-g1234\n', '')
+    gpg_result = self.wrapper.RunResult(0, '', '')
+    with mock.patch.object(self.wrapper, 'run_git',
+                           side_effect=(desc_result, gpg_result)):
+      ret = self.wrapper.verify_rev('/', 'refs/heads/stable', '1234', True)
+      self.assertEqual('v1.0^0', ret)
+
+  def test_verify_fails(self):
+    """Check we fall back to signed tag when we have an unsigned commit."""
+    desc_result = self.wrapper.RunResult(0, 'v1.0-10-g1234\n', '')
+    gpg_result = Exception
+    with mock.patch.object(self.wrapper, 'run_git',
+                           side_effect=(desc_result, gpg_result)):
+      with self.assertRaises(Exception):
+        self.wrapper.verify_rev('/', 'refs/heads/stable', '1234', True)
+
+
+class GitCheckoutTestCase(RepoWrapperTestCase):
+  """Tests that use a real/small git checkout."""
 
   GIT_DIR = None
   REV_LIST = None
@@ -274,6 +373,10 @@ class ResolveRepoRev(RepoWrapperTestCase):
 
     shutil.rmtree(cls.GIT_DIR)
 
+
+class ResolveRepoRev(GitCheckoutTestCase):
+  """Check resolve_repo_rev behavior."""
+
   def test_explicit_branch(self):
     """Check refs/heads/branch argument."""
     rrev, lrev = self.wrapper.resolve_repo_rev(self.GIT_DIR, 'refs/heads/stable')
@@ -328,5 +431,54 @@ class ResolveRepoRev(RepoWrapperTestCase):
       self.wrapper.resolve_repo_rev(self.GIT_DIR, 'boooooooya')
 
 
+class CheckRepoVerify(RepoWrapperTestCase):
+  """Check check_repo_verify behavior."""
+
+  def test_no_verify(self):
+    """Always fail with --no-repo-verify."""
+    self.assertFalse(self.wrapper.check_repo_verify(False))
+
+  def test_gpg_initialized(self):
+    """Should pass if gpg is setup already."""
+    with mock.patch.object(self.wrapper, 'NeedSetupGnuPG', return_value=False):
+      self.assertTrue(self.wrapper.check_repo_verify(True))
+
+  def test_need_gpg_setup(self):
+    """Should pass/fail based on gpg setup."""
+    with mock.patch.object(self.wrapper, 'NeedSetupGnuPG', return_value=True):
+      with mock.patch.object(self.wrapper, 'SetupGnuPG') as m:
+        m.return_value = True
+        self.assertTrue(self.wrapper.check_repo_verify(True))
+
+        m.return_value = False
+        self.assertFalse(self.wrapper.check_repo_verify(True))
+
+
+class CheckRepoRev(GitCheckoutTestCase):
+  """Check check_repo_rev behavior."""
+
+  def test_verify_works(self):
+    """Should pass when verification passes."""
+    with mock.patch.object(self.wrapper, 'check_repo_verify', return_value=True):
+      with mock.patch.object(self.wrapper, 'verify_rev', return_value='12345'):
+        rrev, lrev = self.wrapper.check_repo_rev(self.GIT_DIR, 'stable')
+    self.assertEqual('refs/heads/stable', rrev)
+    self.assertEqual('12345', lrev)
+
+  def test_verify_fails(self):
+    """Should fail when verification fails."""
+    with mock.patch.object(self.wrapper, 'check_repo_verify', return_value=True):
+      with mock.patch.object(self.wrapper, 'verify_rev', side_effect=Exception):
+        with self.assertRaises(Exception):
+          self.wrapper.check_repo_rev(self.GIT_DIR, 'stable')
+
+  def test_verify_ignore(self):
+    """Should pass when verification is disabled."""
+    with mock.patch.object(self.wrapper, 'verify_rev', side_effect=Exception):
+      rrev, lrev = self.wrapper.check_repo_rev(self.GIT_DIR, 'stable', repo_verify=False)
+    self.assertEqual('refs/heads/stable', rrev)
+    self.assertEqual(self.REV_LIST[1], lrev)
+
+
 if __name__ == '__main__':
   unittest.main()