Bug 1516847 - Update help and remove support for 'mach test' with no arguments; r=ahal

Differential Revision: https://phabricator.services.mozilla.com/D78804

testing/mach_commands.py

@@ -28,9 +28,7 @@ UNKNOWN_TEST = '''
 I was unable to find tests from the given argument(s).
 
 You should specify a test directory, filename, test suite name, or
-abbreviation. If no arguments are given, there must be local file
-changes and corresponding IMPACTED_TESTS annotations in moz.build
-files relevant to those files.
+abbreviation.
 
 It's possible my little brain doesn't know about the type of test you are
 trying to execute. If you suspect this, please request support by filing
@@ -305,11 +303,6 @@ class Test(MachCommandBase):
         * A test suite name
         * An alias to a test suite name (codes used on TreeHerder)
 
-        If no input is provided, tests will be run based on files changed in
-        the local tree. Relevant tests, tags, or flavors are determined by
-        IMPACTED_TESTS annotations in moz.build files relevant to the
-        changed files.
-
         When paths or directories are given, they are first resolved to test
         files known to the build system.
 

testing/mozbase/moztest/moztest/resolve.py

@@ -883,23 +883,4 @@ class TestResolver(MozbuildObject):
             if not tests:
                 print('UNKNOWN TEST: %s' % entry, file=sys.stderr)
 
-        if not what:
-            res = self.get_outgoing_metadata()
-            paths, tags, flavors = (res[key] for key in ('paths', 'tags', 'flavors'))
-
-            # This requires multiple calls to resolve_tests, because the test
-            # resolver returns tests that match every condition, while we want
-            # tests that match any condition. Bug 1210213 tracks implementing
-            # more flexible querying.
-            if tags:
-                run_tests = list(self.resolve_tests(tags=tags))
-            if paths:
-                run_tests += [t for t in self.resolve_tests(paths=paths)
-                              if not (tags & set(t.get('tags', '').split()))]
-            if flavors:
-                run_tests = [
-                    t for t in run_tests if t['flavor'] not in flavors]
-                for flavor in flavors:
-                    run_tests += list(self.resolve_tests(flavor=flavor))
-
         return run_suites, run_tests