test_runner: cache shouldSkipFileCoverage result per URL

Han5991 · aduh95 · commit c048b3afc7ee · 2026-07-21T15:24:52.000+02:00
`shouldSkipFileCoverage(url)` is invoked twice for every covered script (once during source-map mapping and once during merge), and the same script URL is typically reported by every worker. The result depends only on `options.cwd`, `coverageExcludeGlobs`, and `coverageIncludeGlobs`, all of which are fixed for the lifetime of a TestCoverage instance, so the URL -> boolean mapping is deterministic and safe to cache. Add a private `#skipCache` SafeMap and split the method into a thin caching wrapper plus a private `#computeShouldSkipFileCoverage` that holds the original logic. Callers are unchanged. This eliminates redundant glob and URL parsing work proportional to the number of workers x scripts in the coverage report. Refs: #55103 Signed-off-by: sangwook <rewq5991@gmail.com> PR-URL: #63675 Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Moshe Atlow <moshe@atlow.co.il> Reviewed-By: Chemi Atlow <chemi@atlow.co.il>
diff --git a/lib/internal/test_runner/coverage.js b/lib/internal/test_runner/coverage.js
@@ -86,6 +86,7 @@ class TestCoverage {
 
   #sourceLines = new SafeMap();
   #typeScriptLines = new SafeSet();
+  #skipCache = new SafeMap();
 
   getLines(fileUrl, source) {
     // Split the file source into lines. Make sure the lines maintain their
@@ -535,6 +536,14 @@ class TestCoverage {
   }
 
   shouldSkipFileCoverage(url) {
+    const cached = this.#skipCache.get(url);
+    if (cached !== undefined) return cached;
+    const result = this.#computeShouldSkipFileCoverage(url);
+    this.#skipCache.set(url, result);
+    return result;
+  }
+
+  #computeShouldSkipFileCoverage(url) {
     // This check filters out core modules, which start with 'node:' in
     // coverage reports, as well as any invalid coverages which have been
     // observed on Windows.
