DAS: check initializers and test generics with convert_class_to_enum

Change-Id: Iefdabed95a8078c58ecfd6b19f5ca99f20710103
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/475500
Commit-Queue: Samuel Rawlins <srawlins@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>

Author: srawlins

pkg/analysis_server/lib/src/services/correction/dart/convert_class_to_enum.dart

@@ -384,6 +384,7 @@ class _EnumDescription {
 
       if (constructor.documentationComment != null) return null;
       if (constructor.metadata.isNotEmpty) return null;
+      if (constructor.initializers.isNotEmpty) return null;
 
       var parameters = constructor.parameters.parameters;
       // If there's only one constructor, then there can only be one entry in the
@@ -402,8 +403,11 @@ class _EnumDescription {
       var name = primaryConstructor.constructorName?.name.lexeme;
       if (name != null && name != 'new') return null;
 
-      if (primaryConstructor.body?.documentationComment != null) return null;
-      if (primaryConstructor.body?.metadata.isNotEmpty ?? false) return null;
+      if (primaryConstructor.body case var body?) {
+        if (body.documentationComment != null) return null;
+        if (body.metadata.isNotEmpty) return null;
+        if (body.initializers.isNotEmpty) return null;
+      }
 
       var parameters = primaryConstructor.formalParameters.parameters;
       // If there's only one constructor, then there can only be one entry in the

pkg/analysis_server/test/src/services/correction/assist/convert_class_to_enum_test.dart

@@ -679,6 +679,23 @@ enum _E {
 ''');
   }
 
+  Future<void> test_minimal_privateClass_constructorHasInitializers() async {
+    await resolveTestCode('''
+class _^E {
+  static const _E c = _E();
+
+  const _E() : assert(1 == 1);
+}
+''');
+    await assertHasAssist('''
+enum _E {
+  c;
+
+  const _E() : assert(1 == 1);
+}
+''');
+  }
+
   Future<void> test_minimal_privateClass_primaryConstructor() async {
     await resolveTestCode('''
 class const _^E() {
@@ -692,6 +709,19 @@ enum _E {
 ''');
   }
 
+  Future<void> test_minimal_privateClass_primaryConstructor_generic() async {
+    await resolveTestCode('''
+class const _^E<T>() {
+  static const _E c = _E();
+}
+''');
+    await assertHasAssist('''
+enum _E<T> {
+  c
+}
+''');
+  }
+
   Future<void>
   test_minimal_privateClass_primaryConstructorHasAnnotation() async {
     await resolveTestCode('''
@@ -795,7 +825,7 @@ enum E {
 ''');
   }
 
-  Future<void> test_noIndex_notInt_primaryClass() async {
+  Future<void> test_noIndex_notInt_primaryConstructor() async {
     await resolveTestCode('''
 class const ^E._(final String name) {
   static const E c0 = E._('c0');