Add test for overloads.

Author: DanielRosenwasser

internal/fourslash/tests/codeLensOverloads01_test.go

@@ -0,0 +1,39 @@
+package fourslash_test
+
+import (
+	"testing"
+
+	"github.com/microsoft/typescript-go/internal/fourslash"
+	"github.com/microsoft/typescript-go/internal/ls/lsutil"
+	"github.com/microsoft/typescript-go/internal/testutil"
+)
+
+func TestCodeLensOverloads01(t *testing.T) {
+	t.Parallel()
+	defer testutil.RecoverAndFail(t, "Panic on fourslash test")
+
+	const content = `
+export function foo(x: number): number;
+export function foo(x: string): string;
+export function foo(x: string | number): string | number {
+	return x;
+}
+
+foo(1);
+
+foo("hello");
+
+// This one isn't expected to match any overload,
+// but is really just here to test how it affects how code lens.
+foo(Math.random() ? 1 : "hello");
+`
+	f := fourslash.NewFourslash(t, nil /*capabilities*/, content)
+	f.VerifyBaselineCodeLens(t, &lsutil.UserPreferences{
+		ReferencesCodeLensEnabled:            true,
+		ReferencesCodeLensShowOnAllFunctions: true,
+
+		ImplementationsCodeLensEnabled:                true,
+		ImplementationsCodeLensShowOnInterfaceMethods: true,
+		ImplementationsCodeLensShowOnAllClassMethods:  true,
+	})
+}