simplify testing by removing unnecessary reference

The assumption should really be that the HEAD of the repo is the current noise reference. There is therefore no need to store a special reference hash for the tests. This simplifies things quite a bit, in particular by not requiring submitters to update a reference.

This commit drops the reference and modifies the test to just compare the current code against HEAD by default. The option to compare against an arbitrary ref is preserved.

The CI is updated for these simplifications. The "test" job is now simple generation of the budgets. The merge request approval job is renamed 'review:noise_change_approval`, and it's logic remains mostly the same: it compares the current budgets against the head of the MR target branch, and requires the same MR approval to pass. The overall MR approval process therefor doesn't change.

gwinc/test/__main__.py

@@ -42,28 +42,10 @@ def git_ref_resolve_hash(git_ref):
         return subprocess.run(
             ['git', 'show', '-s', '--format=format:%H', git_ref],
             capture_output=True, universal_newlines=True,
+            check=True,
         ).stdout
-    except subprocess.CalledProcessError:
-        return None
-
-
-def write_ref_hash(ref_hash):
-    """Write ref hash to reference file
-
-    """
-    with open(test_path('ref_hash'), 'w') as f:
-        f.write('{}\n'.format(ref_hash))
-
-
-def load_ref_hash():
-    """Load the current reference git hash.
-
-    """
-    try:
-        with open(test_path('ref_hash')) as f:
-            return f.read().strip()
-    except IOError:
-        return None
+    except subprocess.CalledProcessError as e:
+        logging.error(e.stderr.split('\n')[0])
 
 
 def prune_cache_dir():
@@ -79,7 +61,7 @@ def prune_cache_dir():
     )[CACHE_LIMIT:]
     if not expired_paths:
         return
-    logging.info("pruning {} old caches...".format(len(expired_paths)))
+    logging.info("pruning {} old cache...".format(len(expired_paths)))
     for path in expired_paths:
         logging.debug("pruning {}...".format(path))
         shutil.rmtree(path)
@@ -248,12 +230,9 @@ def main():
         '--skip', '-k', metavar='NOISE', action='append',
         help='traces to skip in comparison (multiple may be specified)')
     parser.add_argument(
-        '--git-ref', '-g', metavar='HASH',
+        '--git-ref', '-g', metavar='HASH', default='HEAD',
         help='specify git ref to compare against')
     rgroup = parser.add_mutually_exclusive_group()
-    rgroup.add_argument(
-        '--update-ref', '-u', metavar='HASH', nargs='?', const='HEAD',
-        help="update the stored reference git hash to HASH (or 'HEAD' if not specified) and exit")
     rgroup.add_argument(
         '--plot', '-p', action='store_true',
         help='plot differences')
@@ -265,46 +244,11 @@ def main():
         help='specific ifos to test (default all)')
     args = parser.parse_args()
 
-    # get the current hash of HEAD
-    head_hash = git_ref_resolve_hash('HEAD')
-    if not head_hash:
-        logging.warning("could not determine git HEAD hash.")
-
-    # update the reference if specified
-    if args.update_ref:
-        if args.update_ref == 'HEAD':
-            if not head_hash:
-                sys.exit("Could not update reference to head.")
-            logging.info("updating reference to HEAD...")
-            ref_hash = head_hash
-        else:
-            ref_hash = git_ref_resolve_hash(args.update_ref)
-        logging.info("updating reference git hash: {}".format(ref_hash))
-        write_ref_hash(ref_hash)
-        sys.exit()
-
     # get the reference hash
-    if args.git_ref:
-        ref_hash = git_ref_resolve_hash(args.git_ref)
-    else:
-        ref_hash = load_ref_hash()
-        if not ref_hash:
-            pass
-        try:
-            with open(test_path('ref_hash')) as f:
-                ref_hash = f.read().strip()
-        except IOError:
-            logging.warning("could not open reference")
-            sys.exit("Unspecified reference git hash, could not run test.")
-
-    logging.info("head hash: {}".format(head_hash))
-    logging.info("ref  hash: {}".format(ref_hash))
-
-    # don't bother test if hashes match
-    if ref_hash == head_hash:
-        logging.info("HEAD matches reference, not bothering to calculate.")
-        logging.info("Use --git-ref to compare against an arbitrary git commit.")
-        sys.exit()
+    ref_hash = git_ref_resolve_hash(args.git_ref)
+    if not ref_hash:
+        sys.exit("Could not resolve reference, could not run test.")
+    logging.info("ref hash: {}".format(ref_hash))
 
     # load the cache
     cache_path = test_path('cache', ref_hash)