Little command to benchmark matchers

nomenklatura/cli.py

@@ -23,6 +23,7 @@
 from nomenklatura.stream import StreamEntity
 from nomenklatura.xref import xref as run_xref
 from nomenklatura.tui import dedupe_ui
+from nomenklatura.matching.bench import bench_matcher
 
 INDEX_SEGMENT = "xref-index"
 
@@ -308,5 +309,13 @@ def statements_aggregate(
             write_entity(outfh, entity)
 
 
+@cli.command("bench", help="Benchmark a matching algorithm")
+@click.argument("name", type=str)
+@click.argument("pairs_file", type=InPath)
+@click.option("-n", "--number", type=int, default=1000)
+def bench(name: str, pairs_file: Path, number: int = 1000) -> None:
+    bench_matcher(name, pairs_file, number)
+
+
 if __name__ == "__main__":
     cli()

nomenklatura/matching/bench.py

@@ -0,0 +1,30 @@
+import datetime
+from timeit import timeit
+from itertools import cycle
+import logging
+
+from nomenklatura.matching import get_algorithm
+from nomenklatura.matching.pairs import read_pairs
+from nomenklatura.util import PathLike
+
+
+log = logging.getLogger(__name__)
+
+
+def bench_matcher(name: str, pairs_file: PathLike, number: int) -> None:
+    log.info("Loading pairs from %s", pairs_file)
+    pairs = list(read_pairs(pairs_file))
+    log.info("Read %d pairs", len(pairs))
+    matcher = get_algorithm(name)
+    if matcher is None:
+        raise ValueError("No matcher named %s", name)
+    log.info("Loaded %s", matcher.NAME)
+    infinite_pairs = cycle(pairs)
+
+    def compare_one_pair() -> None:
+        pair = next(infinite_pairs)
+        matcher.compare(pair.left, pair.right)
+
+    log.info("Running benchmark for %d iterations", number)
+    seconds = timeit(compare_one_pair, number=number)
+    log.info("Total time %s", datetime.timedelta(seconds=seconds))