[analyzer] Dot shorthand: Update constant verification for default parameter values.

The constant visitor was missing an extra check that we had for instance creation expressions, but not for dot shorthand constructor invocations. It's definitely a little funky because of how we've chained up the ConstantVisitor + ConstantVerifier, but this is how we currently handle this error.

Added a unit test.

Fixes: #60962
Bug: #59835
Change-Id: I76489a425c5e01c4d9edb34ac6dc62f109e6a32a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/436821
Commit-Queue: Kallen Tu <[email protected]>
Reviewed-by: Chloe Stefantsova <[email protected]>

Author: kallentu

pkg/analyzer/lib/src/dart/constant/evaluation.dart

@@ -896,6 +896,14 @@ class ConstantVisitor extends UnifyingAstVisitor<Constant> {
   Constant visitDotShorthandConstructorInvocation(
     covariant DotShorthandConstructorInvocationImpl node,
   ) {
+    // This check is used by the [ConstantVerifier] to check for constant
+    // default parameters and other instances where the invocation must be
+    // constant.
+    if (!node.isConst) {
+      // TODO(kallentu): Use a specific error code.
+      // https://github.com/dart-lang/sdk/issues/47061
+      return InvalidConstant.genericError(node: node);
+    }
     var constructor = node.constructorName.element;
     if (constructor is ConstructorElementMixin2) {
       return _evaluationEngine.evaluateAndFormatErrorsInConstructorCall(

pkg/analyzer/test/src/diagnostics/non_constant_default_value_test.dart

@@ -39,6 +39,19 @@ class A {
     );
   }
 
+  test_dotShorthand_issue60962() async {
+    await assertErrorsInCode(
+      r'''
+class A {
+  const A();
+}
+
+void f([A a = .new()]) {}
+''',
+      [error(CompileTimeErrorCode.NON_CONSTANT_DEFAULT_VALUE, 40, 6)],
+    );
+  }
+
   test_enum_issue49097() async {
     newFile('$testPackageLibPath/a.dart', r'''
 class A {