Infer parameter types on overrides

Fixes #105

This overlaps with brian's recent CL moving override inference logic.  If this looks good, we'll need to move it over as well.

[email protected], [email protected]

Review URL: https://codereview.chromium.org/1311863005 .

Author: vsmenon

pkg/dev_compiler/lib/runtime/dart/js.js

@@ -201,15 +201,15 @@ dart_library.library('dart/js', null, /* Imports */[
         }
       }
       get(index) {
-        if (dart.is(index, core.num) && dart.equals(index, dart.dsend(index, 'toInt'))) {
-          this[_checkIndex](dart.as(index, core.int));
+        if (dart.is(index, core.num) && index == index[dartx.toInt]()) {
+          this[_checkIndex](index);
         }
         return dart.as(super.get(index), E);
       }
       set(index, value) {
         dart.as(value, E);
-        if (dart.is(index, core.num) && dart.equals(index, dart.dsend(index, 'toInt'))) {
-          this[_checkIndex](dart.as(index, core.int));
+        if (dart.is(index, core.num) && index == index[dartx.toInt]()) {
+          this[_checkIndex](index);
         }
         super.set(index, value);
       }
@@ -282,8 +282,8 @@ dart_library.library('dart/js', null, /* Imports */[
       methods: () => ({
         [_checkIndex]: [dart.dynamic, [core.int]],
         [_checkInsertIndex]: [dart.dynamic, [core.int]],
-        get: [E, [dart.dynamic]],
-        set: [dart.void, [dart.dynamic, E]],
+        get: [E, [core.int]],
+        set: [dart.void, [core.int, E]],
         add: [dart.void, [E]],
         addAll: [dart.void, [core.Iterable$(E)]],
         insert: [dart.void, [core.int, E]],

pkg/dev_compiler/lib/src/checker/resolver.dart

@@ -168,10 +168,10 @@ class LibraryResolverWithInference extends LibraryResolver {
             .forEach((f) => _inferFieldTypeFromOverride(f, pending));
         if (pending.isNotEmpty) _inferVariableFromInitializer(pending);
 
-        // Infer return-types from overrides
+        // Infer return-types and param-types from overrides
         cls.members
             .where((m) => m is MethodDeclaration && !m.isStatic)
-            .forEach(_inferMethodReturnTypeFromOverride);
+            .forEach(_inferMethodTypesFromOverride);
       } else {
         _inferVariableFromInitializer(cls.members
             .where(_isInstanceField)
@@ -231,18 +231,38 @@ class LibraryResolverWithInference extends LibraryResolver {
     }
   }
 
-  void _inferMethodReturnTypeFromOverride(MethodDeclaration method) {
+  void _inferMethodTypesFromOverride(MethodDeclaration method) {
     var methodElement = method.element;
-    if ((methodElement is MethodElement ||
-            methodElement is PropertyAccessorElement) &&
-        methodElement.returnType.isDynamic &&
-        method.returnType == null) {
-      var enclosingElement = methodElement.enclosingElement as ClassElement;
-      var type = searchTypeFor(enclosingElement.type, methodElement);
-      if (type != null && !type.returnType.isDynamic) {
+    if (methodElement is! MethodElement &&
+        methodElement is! PropertyAccessorElement) return;
+
+    var enclosingElement = methodElement.enclosingElement as ClassElement;
+    FunctionType type = null;
+
+    // Infer the return type if omitted
+    if (methodElement.returnType.isDynamic && method.returnType == null) {
+      type = searchTypeFor(enclosingElement.type, methodElement);
+      if (type == null) return;
+      if (!type.returnType.isDynamic) {
         methodElement.returnType = type.returnType;
       }
     }
+
+    // Infer parameter types if omitted
+    if (method.parameters == null) return;
+    var parameters = method.parameters.parameters;
+    var length = parameters.length;
+    for (int i = 0; i < length; ++i) {
+      var parameter = parameters[i];
+      if (parameter is DefaultFormalParameter) parameter = parameter.parameter;
+      if (parameter is SimpleFormalParameter && parameter.type == null) {
+        type = type ?? searchTypeFor(enclosingElement.type, methodElement);
+        if (type == null) return;
+        if (type.parameters.length > i && !type.parameters[i].type.isDynamic) {
+          parameter.element.type = type.parameters[i].type;
+        }
+      }
+    }
   }
 
   void _inferVariableFromInitializer(Iterable<VariableDeclaration> variables) {

pkg/dev_compiler/test/checker/checker_test.dart

@@ -1488,7 +1488,7 @@ void main() {
           class Child extends Base {
             void set f1(A value) {}
             /*severe:InvalidMethodOverride*/void set f2(C value) {}
-            /*severe:InvalidMethodOverride*/void set f3(value) {}
+            void set f3(value) {}
             /*severe:InvalidMethodOverride*/void set f4(dynamic value) {}
             set f5(B value) {}
           }
@@ -1518,7 +1518,7 @@ void main() {
 
             void set f1(A value) {}
             /*severe:InvalidMethodOverride*/void set f2(C value) {}
-            /*severe:InvalidMethodOverride*/void set f3(value) {}
+            void set f3(value) {}
             /*severe:InvalidMethodOverride*/void set f4(dynamic value) {}
             set f5(B value) {}
           }
@@ -1547,7 +1547,7 @@ void main() {
             /*severe:InvalidMethodOverride*/C m2(C value) {}
             /*severe:InvalidMethodOverride*/A m3(C value) {}
             C m4(A value) {}
-            /*severe:InvalidMethodOverride*/m5(value) {}
+            m5(value) {}
             /*severe:InvalidMethodOverride*/dynamic m6(dynamic value) {}
           }
        '''
@@ -2025,14 +2025,14 @@ void main() {
                 implements I1 {}
 
             class T2 extends Base implements I1 {
-                /*severe:InvalidMethodOverride,severe:InvalidMethodOverride*/m(a) {}
+                /*severe:InvalidMethodOverride*/m(a) {}
             }
 
             class T3 extends Object with /*severe:InvalidMethodOverride*/Base
                 implements I1 {}
 
             class T4 extends Object with Base implements I1 {
-                /*severe:InvalidMethodOverride,severe:InvalidMethodOverride*/m(a) {}
+                /*severe:InvalidMethodOverride*/m(a) {}
             }
          '''
     });

pkg/dev_compiler/tool/sdk_expected_errors.txt

@@ -3,23 +3,23 @@ severe: [AnalyzerMessage] Classes cannot implement 'num' (dart:_interceptors/js_
 severe: [AnalyzerMessage] The return type 'JSNumber' is not a 'double', as defined by the method 'toDouble' (dart:_interceptors/js_number.dart, line 110, col 17)
 severe: [StaticTypeError] Type check failed: this (JSNumber) is not of type double (dart:_interceptors/js_number.dart, line 110, col 17)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.sign (() → num) is not a subtype of int.sign (() → int). (dart:_interceptors/js_number.dart, line 349, col 13)
-severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.>> ((num) → num) is not a subtype of int.>> ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
+severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.& ((num) → num) is not a subtype of int.& ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.abs (() → num) is not a subtype of int.abs (() → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.unary- (() → num) is not a subtype of int.unary- (() → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.<< ((num) → num) is not a subtype of int.<< ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
-severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.& ((num) → num) is not a subtype of int.& ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
+severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.>> ((num) → num) is not a subtype of int.>> ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.| ((num) → num) is not a subtype of int.| ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.^ ((num) → num) is not a subtype of int.^ ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [AnalyzerMessage] Classes cannot implement 'int' (dart:_interceptors/js_number.dart, line 349, col 41)
 severe: [AnalyzerMessage] Classes cannot implement 'double' (dart:_interceptors/js_number.dart, line 349, col 46)
-severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.sign (() → num) is not a subtype of double.sign (() → double). (dart:_interceptors/js_number.dart, line 420, col 16)
-severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.% ((num) → num) is not a subtype of double.% ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
-severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.* ((num) → num) is not a subtype of double.* ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
-severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.- ((num) → num) is not a subtype of double.- ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
-severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.+ ((num) → num) is not a subtype of double.+ ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.unary- (() → num) is not a subtype of double.unary- (() → double). (dart:_interceptors/js_number.dart, line 420, col 16)
-severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.abs (() → num) is not a subtype of double.abs (() → double). (dart:_interceptors/js_number.dart, line 420, col 16)
+severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.sign (() → num) is not a subtype of double.sign (() → double). (dart:_interceptors/js_number.dart, line 420, col 16)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.remainder ((num) → num) is not a subtype of double.remainder ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
+severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.abs (() → num) is not a subtype of double.abs (() → double). (dart:_interceptors/js_number.dart, line 420, col 16)
+severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.+ ((num) → num) is not a subtype of double.+ ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
+severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.- ((num) → num) is not a subtype of double.- ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
+severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.* ((num) → num) is not a subtype of double.* ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
+severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.% ((num) → num) is not a subtype of double.% ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
 severe: [AnalyzerMessage] Classes cannot implement 'double' (dart:_interceptors/js_number.dart, line 420, col 44)
 severe: [AnalyzerMessage] Classes cannot implement 'String' (dart:_interceptors/js_string.dart, line 14, col 47)
 severe: [StaticTypeError] Type check failed: s += s (String) is not of type JSString (dart:_interceptors/js_string.dart, line 346, col 7)