gogio: deduplicate Android jars

gogio/androidbuild_test.go

@@ -50,6 +50,48 @@ func TestAndroidExtraJarsIncludesModuleRootAndroidSubdirectory(t *testing.T) {
 	}
 }
 
+func TestAndroidExtraJarsDoesNotRepeatSharedModuleJarWhenCollectedAcrossPackages(t *testing.T) {
+	t.Parallel()
+
+	root := t.TempDir()
+	moduleAndroidJar := filepath.Join(root, "android", "keepassgo-android.jar")
+	writeTestFile(t, filepath.Join(root, "go.mod"), "module example.invalid/crew\n")
+	writeTestFile(t, moduleAndroidJar, "module-android")
+
+	dirs := []string{
+		filepath.Join(root, "cmd", "keepassgo"),
+		filepath.Join(root, "internal", "appui"),
+	}
+	seen := make(map[string]bool)
+	var collected []string
+	for _, dir := range dirs {
+		if err := os.MkdirAll(dir, 0o755); err != nil {
+			t.Fatalf("MkdirAll(%q) error = %v", dir, err)
+		}
+		jars, err := androidExtraJars(dir, root)
+		if err != nil {
+			t.Fatalf("androidExtraJars(%q) error = %v", dir, err)
+		}
+		for _, jar := range jars {
+			if seen[jar] {
+				continue
+			}
+			seen[jar] = true
+			collected = append(collected, jar)
+		}
+	}
+
+	count := 0
+	for _, jar := range collected {
+		if jar == moduleAndroidJar {
+			count++
+		}
+	}
+	if count != 1 {
+		t.Fatalf("collected module jar count = %d, want 1 in %v", count, collected)
+	}
+}
+
 func TestRenderAndroidManifestIncludesOptionalSnippets(t *testing.T) {
 	t.Parallel()