Add 'late' as a feature for final variables

lib/src/model/field.dart

@@ -92,6 +92,9 @@ class Field extends ModelElement
     return field.isFinal;
   }
 
+  @override
+  bool get isLate => isFinal && field.isLate;
+
   @override
   bool get isInherited => _isInherited;
 

lib/src/model/model_element.dart

@@ -43,6 +43,7 @@ const Map<String, int> featureOrder = {
   'read / write': 1,
   'covariant': 2,
   'final': 2,
+  'late': 2,
   'inherited': 3,
   'inherited-getter': 3,
   'inherited-setter': 3,
@@ -499,6 +500,7 @@ abstract class ModelElement extends Canonicalization
     // const and static are not needed here because const/static elements get
     // their own sections in the doc.
     if (isFinal) allFeatures.add('final');
+    if (isLate) allFeatures.add('late');
     return allFeatures;
   }
 
@@ -897,6 +899,8 @@ abstract class ModelElement extends Canonicalization
 
   bool get isFinal => false;
 
+  bool get isLate => false;
+
   bool get isLocalElement => element is LocalElement;
 
   bool get isPropertyAccessor => element is PropertyAccessorElement;

lib/src/model/top_level_variable.dart

@@ -65,6 +65,9 @@ class TopLevelVariable extends ModelElement
     return _variable.isFinal;
   }
 
+  @override
+  bool get isLate => isFinal && _variable.isLate;
+
   @override
   String get kind => isConst ? 'top-level constant' : 'top-level property';
 

test/model_special_cases_test.dart

@@ -36,19 +36,42 @@ void main() {
           .firstWhere((lib) => lib.name == 'late_final_without_initializer');
     });
 
-    test('Late finals test', () {
+    test('Late final class member test', () {
       Class c = lateFinalWithoutInitializer.allClasses
           .firstWhere((c) => c.name == 'C');
       Field a = c.allFields.firstWhere((f) => f.name == 'a');
       Field b = c.allFields.firstWhere((f) => f.name == 'b');
       Field cField = c.allFields.firstWhere((f) => f.name == 'cField');
       Field dField = c.allFields.firstWhere((f) => f.name == 'dField');
-      // If nnbd isn't enabled, fields named 'late' come back from the analyzer.
+
+      // If nnbd isn't enabled, fields named 'late' come back from the analyzer
+      // instead of setting up 'isLate'.
       expect(c.allFields.any((f) => f.name == 'late'), isFalse);
+
       expect(a.modelType.returnType.name, equals('dynamic'));
+      expect(a.isLate, isTrue);
+      expect(a.features, contains('late'));
+
       expect(b.modelType.returnType.name, equals('int'));
+      expect(b.isLate, isTrue);
+      expect(b.features, contains('late'));
+
       expect(cField.modelType.returnType.name, equals('dynamic'));
+      expect(cField.isLate, isTrue);
+      expect(cField.features, contains('late'));
+
       expect(dField.modelType.returnType.name, equals('double'));
+      expect(dField.isLate, isTrue);
+      expect(dField.features, contains('late'));
+    });
+
+    test('Late final top level variables', () {
+      TopLevelVariable initializeMe = lateFinalWithoutInitializer
+          .publicProperties
+          .firstWhere((v) => v.name == 'initializeMe');
+      expect(initializeMe.modelType.returnType.name, equals('String'));
+      expect(initializeMe.isLate, isTrue);
+      expect(initializeMe.features, contains('late'));
     });
   });
 

test/model_test.dart

@@ -2513,6 +2513,7 @@ String topLevelFunction(int param1, bool param2, Cool coolBeans,
     Field explicitGetterSetter;
     Field explicitNonDocumentedInBaseClassGetter;
     Field documentedPartialFieldInSubclassOnly;
+    Field finalProperty;
     Field ExtraSpecialListLength;
     Field aProperty;
     Field covariantField, covariantSetter;
@@ -2539,6 +2540,8 @@ String topLevelFunction(int param1, bool param2, Cool coolBeans,
               (e) => e.name == 'explicitNonDocumentedInBaseClassGetter');
       documentedPartialFieldInSubclassOnly = UnusualProperties.allModelElements
           .firstWhere((e) => e.name == 'documentedPartialFieldInSubclassOnly');
+      finalProperty = UnusualProperties.allModelElements
+          .firstWhere((e) => e.name == 'finalProperty');
 
       isEmpty =
           CatString.allInstanceFields.firstWhere((p) => p.name == 'isEmpty');
@@ -2774,8 +2777,18 @@ String topLevelFunction(int param1, bool param2, Cool coolBeans,
       expect(constField.isConst, isTrue);
     });
 
-    test('is not final', () {
+    test('is final only when appropriate', () {
       expect(f1.isFinal, isFalse);
+      expect(finalProperty.isFinal, isTrue);
+      expect(finalProperty.isLate, isFalse);
+      expect(finalProperty.features, contains('final'));
+      expect(finalProperty.features, isNot(contains('late')));
+      expect(onlySetter.isFinal, isFalse);
+      expect(onlySetter.features, isNot(contains('final')));
+      expect(onlySetter.features, isNot(contains('late')));
+      expect(dynamicGetter.isFinal, isFalse);
+      expect(dynamicGetter.features, isNot(contains('final')));
+      expect(dynamicGetter.features, isNot(contains('late')));
     });
 
     test('is not static', () {
@@ -2885,11 +2898,13 @@ String topLevelFunction(int param1, bool param2, Cool coolBeans,
     TopLevelVariable setAndGet, mapWithDynamicKeys;
     TopLevelVariable nodocGetter, nodocSetter;
     TopLevelVariable complicatedReturn;
-    TopLevelVariable importantComputations;
+    TopLevelVariable meaningOfLife, importantComputations;
 
     setUpAll(() {
       v = exLibrary.properties.firstWhere((p) => p.name == 'number');
       v3 = exLibrary.properties.firstWhere((p) => p.name == 'y');
+      meaningOfLife =
+          fakeLibrary.properties.firstWhere((v) => v.name == 'meaningOfLife');
       importantComputations = fakeLibrary.properties
           .firstWhere((v) => v.name == 'importantComputations');
       complicatedReturn = fakeLibrary.properties
@@ -2908,6 +2923,19 @@ String topLevelFunction(int param1, bool param2, Cool coolBeans,
           .firstWhere((p) => p.name == 'mapWithDynamicKeys');
     });
 
+    test('Verify that final and late show up (or not) appropriately', () {
+      expect(meaningOfLife.isFinal, isTrue);
+      expect(meaningOfLife.isLate, isFalse);
+      expect(meaningOfLife.features, contains('final'));
+      expect(meaningOfLife.features, isNot(contains('late')));
+      expect(justGetter.isFinal, isFalse);
+      expect(justGetter.features, isNot(contains('final')));
+      expect(justGetter.features, isNot(contains('late')));
+      expect(justSetter.isFinal, isFalse);
+      expect(justSetter.features, isNot(contains('final')));
+      expect(justSetter.features, isNot(contains('late')));
+    });
+
     test(
         'Verify that a map containing anonymous functions as values works correctly',
         () {

testing/test_package_experiments/lib/late_final_without_initializer.dart

@@ -4,6 +4,8 @@
 
 import 'dart:math';
 
+late final String initializeMe;
+
 class C {
   late final a;
   late final b = 0;