Checker: a result with skipped tests keeps no verdict, so a skipped pass is run again (issue 890)

modules/mesh-delivery-checker/internal/check/kept.go

@@ -56,9 +56,15 @@ func (k Kept) Keep(ctx context.Context, level, digest string, v delivery.Kept) (
 
 // KeepPasses keeps, for the packages of a test result that passed with tests, a verdict under the digest the build module
 // named for the package at the level. A package that failed, has no tests or has no digest is never kept (ADR 0444 clause
-// 1): it runs every check. It answers the packages it kept now.
+// 1): it runs every check. A result in which any test skipped keeps nothing: the build module counts skips per result,
+// not per package, so no package of it is known to have run whole, and a pass that skipped (a test needing a toolchain the
+// node lacks) would otherwise be reused for its digest and never run anywhere (issue 890). It answers the packages it
+// kept now.
 func (k Kept) KeepPasses(ctx context.Context, repository, level, toolchain string, res Tested, digests map[string]string, at time.Time) ([]string, error) {
 	var kept []string
+	if res.Skipped > 0 {
+		return kept, nil
+	}
 	for _, p := range res.Packages {
 		digest, ok := digests[p.Package]
 		if !ok || !p.Passed || p.NoTests || p.Tests == 0 {

modules/mesh-delivery-checker/internal/check/kept_test.go

@@ -74,6 +74,19 @@ func TestOnlyPassingPackagesWithADigestAreKept(t *testing.T) { // 1287/AC3, AC4
 	}
 }
 
+func TestAResultWithSkippedTestsKeepsNothing(t *testing.T) { // issue 890: a pass that skipped proved nothing
+	ctx, st := context.Background(), newMemKV()
+	k := Kept{Store: st}
+	res := Tested{Level: "integration", Passed: true, Skipped: 2, Packages: []GoPackage{{Package: "m/a", Passed: true, Tests: 4}}}
+	kept, err := k.KeepPasses(ctx, "novox/mesh-catalog", "integration", "go1.26.0", res, map[string]string{"m/a": digA}, at0)
+	if err != nil || len(kept) != 0 {
+		t.Fatalf("kept %v, %v, want nothing", kept, err)
+	}
+	if keys, _ := st.Keys(ctx); len(keys) != 0 {
+		t.Errorf("the bucket holds %v, want none", keys)
+	}
+}
+
 func TestAKeptValueOfAnotherDigestIsNotRead(t *testing.T) { // 1287/AC7
 	ctx, st := context.Background(), newMemKV()
 	k := Kept{Store: st}