issue 1840/S3: look the declared packages up by name in the mirror's integration test, since every node also runs the mesh's own modules and their packages

cmd/mesh-controller/declared_packages_integration_test.go

@@ -35,19 +35,47 @@ func TestTheDeclaredPackagesMirrorNamesWhatEachNodesModulesDeclare(t *testing.T)
 	if err := json.Unmarshal(first["anchor"], &got); err != nil {
 		t.Fatalf("anchor has no value: %v", err)
 	}
-	want := []inventory.PackageDeclared{{Package: "curl", Modules: []string{"fetcher", "viewer"}},
-		{Package: "nano", Modules: []string{"viewer"}, Absent: true}}
-	if len(got.Packages) != len(want) {
-		t.Fatalf("anchor declares %+v, want %+v", got.Packages, want)
+	// Every node also runs the mesh's own modules, which declare packages of their own: curl and nano are looked
+	// up by name, and no package names viewer or fetcher but those they declare.
+	byName := map[string]inventory.PackageDeclared{}
+	for _, p := range got.Packages {
+		byName[p.Package] = p
 	}
-	for i, p := range want {
-		if g := got.Packages[i]; g.Package != p.Package || g.Absent != p.Absent || len(g.Modules) != len(p.Modules) ||
-			(len(p.Modules) > 0 && g.Modules[0] != p.Modules[0]) {
-			t.Errorf("package %d is %+v, want %+v", i, g, p)
+	same := func(a, b []string) bool {
+		if len(a) != len(b) {
+			return false
+		}
+		for i := range a {
+			if a[i] != b[i] {
+				return false
+			}
+		}
+		return true
+	}
+	for _, p := range []inventory.PackageDeclared{{Package: "curl", Modules: []string{"fetcher", "viewer"}},
+		{Package: "nano", Modules: []string{"viewer"}, Absent: true}} {
+		if g, ok := byName[p.Package]; !ok || g.Absent != p.Absent || !same(g.Modules, p.Modules) {
+			t.Errorf("anchor declares %s as %+v, want %+v (all: %+v)", p.Package, g, p, got.Packages)
 		}
 	}
-	if string(first["laptop"]) != `{"node":"laptop","packages":[]}` {
-		t.Errorf("a node declaring none is %s", first["laptop"])
+	for _, p := range got.Packages {
+		if p.Package == "curl" || p.Package == "nano" {
+			continue
+		}
+		for _, m := range p.Modules {
+			if m == "viewer" || m == "fetcher" {
+				t.Errorf("%s is said to be declared by %s, which does not declare it", p.Package, m)
+			}
+		}
+	}
+	var laptop inventory.DeclaredPackagesMirrored
+	if err := json.Unmarshal(first["laptop"], &laptop); err != nil || laptop.Node != "laptop" || laptop.Packages == nil {
+		t.Errorf("a node assigned neither module has no value of its own: %s (%v)", first["laptop"], err)
+	}
+	for _, p := range laptop.Packages {
+		if p.Package == "curl" || p.Package == "nano" {
+			t.Errorf("laptop is assigned neither module and declares %+v", p)
+		}
 	}
 	second, err := source(ctx)
 	if err != nil {