Pass base branch to module validator on delegate.

test/runner/lib/delegation.py

@@ -15,6 +15,7 @@ from lib.executor import (
     SubprocessError,
     ShellConfig,
     TestConfig,
+    SanityConfig,
     create_shell_command,
 )
 
@@ -354,6 +355,9 @@ def generate_command(args, path, options, exclude, require):
 
     if isinstance(args, ShellConfig):
         cmd = create_shell_command(cmd)
+    elif isinstance(args, SanityConfig):
+        if args.base_branch:
+            cmd += ['--base-branch', args.base_branch]
 
     return cmd
 
@@ -382,6 +386,10 @@ def filter_options(args, argv, options, exclude, require):
             '--changed-from': 1,
             '--changed-path': 1,
         })
+    elif isinstance(args, SanityConfig):
+        options.update({
+            '--base-branch': 1,
+        })
 
     remaining = 0
 

test/runner/lib/executor.py

@@ -35,6 +35,7 @@ from lib.util import (
     ApplicationWarning,
     ApplicationError,
     SubprocessError,
+    MissingEnvironmentVariable,
     display,
     run_command,
     deepest_path,
@@ -796,12 +797,12 @@ def command_sanity_validate_modules(args, targets):
     if skip_paths:
         cmd += ['--exclude', '^(%s)' % '|'.join(skip_paths)]
 
-    if is_shippable():
+    if args.base_branch:
         cmd.extend([
-            '--base-branch', os.environ['BASE_BRANCH']
+            '--base-branch', args.base_branch,
         ])
     else:
-        display.warning("Cannot perform module comparison against the base branch when running locally")
+        display.warning('Cannot perform module comparison against the base branch. Base branch not detected when running locally.')
 
     run_command(args, cmd, env=env)
 
@@ -1378,6 +1379,16 @@ class SanityConfig(TestConfig):
         self.skip_test = args.skip_test  # type: list [str]
         self.list_tests = args.list_tests  # type: bool
 
+        if args.base_branch:
+            self.base_branch = args.base_branch  # str
+        elif is_shippable():
+            try:
+                self.base_branch = os.environ['BASE_BRANCH']  # str
+            except KeyError as ex:
+                raise MissingEnvironmentVariable(name=ex.args[0])
+        else:
+            self.base_branch = ''
+
 
 class IntegrationConfig(TestConfig):
     """Configuration for the integration command."""

test/runner/test.py

@@ -285,6 +285,9 @@ def parse_args():
                         choices=SUPPORTED_PYTHON_VERSIONS,
                         help='python version: %s' % ', '.join(SUPPORTED_PYTHON_VERSIONS))
 
+    sanity.add_argument('--base-branch',
+                        help=argparse.SUPPRESS)
+
     add_extra_docker_options(sanity, integration=False)
 
     shell = subparsers.add_parser('shell',