Handle use of fromEnvironment from serialized data.

This CL removes the [intEnvironment], [boolEnvironment] and [stringEnvironment]
from [Compiler] and instead determine .fromEnvironment directly from the
constructor element itself.

R=sigmund@google.com

Review URL: https://codereview.chromium.org/2033383002 .

pkg/compiler/lib/src/compile_time_constants.dart

@@ -927,10 +927,7 @@ class CompileTimeConstantEvaluator extends Visitor<AstConstant> {
       assert(normalizedArguments != null);
       concreteArguments = normalizedArguments;
     }
-
-    if (constructor == compiler.intEnvironment ||
-        constructor == compiler.boolEnvironment ||
-        constructor == compiler.stringEnvironment) {
+    if (constructor.isFromEnvironmentConstructor) {
       return createFromEnvironmentConstant(node, constructedType, constructor,
           callStructure, normalizedArguments, concreteArguments);
     } else {
@@ -974,7 +971,7 @@ class CompileTimeConstantEvaluator extends Visitor<AstConstant> {
       return null;
     }
 
-    if (constructor == compiler.intEnvironment &&
+    if (constructor.isIntFromEnvironmentConstructor &&
         !(defaultValue.isNull || defaultValue.isInt)) {
       DartType type = defaultValue.getType(coreTypes);
       reporter.reportErrorMessage(
@@ -984,7 +981,7 @@ class CompileTimeConstantEvaluator extends Visitor<AstConstant> {
       return null;
     }
 
-    if (constructor == compiler.boolEnvironment &&
+    if (constructor.isBoolFromEnvironmentConstructor &&
         !(defaultValue.isNull || defaultValue.isBool)) {
       DartType type = defaultValue.getType(coreTypes);
       reporter.reportErrorMessage(
@@ -994,7 +991,7 @@ class CompileTimeConstantEvaluator extends Visitor<AstConstant> {
       return null;
     }
 
-    if (constructor == compiler.stringEnvironment &&
+    if (constructor.isStringFromEnvironmentConstructor &&
         !(defaultValue.isNull || defaultValue.isString)) {
       DartType type = defaultValue.getType(coreTypes);
       reporter.reportErrorMessage(
@@ -1014,13 +1011,13 @@ class CompileTimeConstantEvaluator extends Visitor<AstConstant> {
       if (concreteArguments.length > 1) {
         defaultValue = concreteArguments[1].expression;
       }
-      if (constructor == compiler.intEnvironment) {
+      if (constructor.isIntFromEnvironmentConstructor) {
         expression =
             new IntFromEnvironmentConstantExpression(name, defaultValue);
-      } else if (constructor == compiler.boolEnvironment) {
+      } else if (constructor.isBoolFromEnvironmentConstructor) {
         expression =
             new BoolFromEnvironmentConstantExpression(name, defaultValue);
-      } else if (constructor == compiler.stringEnvironment) {
+      } else if (constructor.isStringFromEnvironmentConstructor) {
         expression =
             new StringFromEnvironmentConstantExpression(name, defaultValue);
       }
@@ -1030,11 +1027,11 @@ class CompileTimeConstantEvaluator extends Visitor<AstConstant> {
 
     if (value == null) {
       return createEvaluatedConstant(defaultValue);
-    } else if (constructor == compiler.intEnvironment) {
+    } else if (constructor.isIntFromEnvironmentConstructor) {
       int number = int.parse(value, onError: (_) => null);
       return createEvaluatedConstant(
           (number == null) ? defaultValue : constantSystem.createInt(number));
-    } else if (constructor == compiler.boolEnvironment) {
+    } else if (constructor.isBoolFromEnvironmentConstructor) {
       if (value == 'true') {
         return createEvaluatedConstant(constantSystem.createBool(true));
       } else if (value == 'false') {
@@ -1043,7 +1040,7 @@ class CompileTimeConstantEvaluator extends Visitor<AstConstant> {
         return createEvaluatedConstant(defaultValue);
       }
     } else {
-      assert(constructor == compiler.stringEnvironment);
+      assert(constructor.isStringFromEnvironmentConstructor);
       return createEvaluatedConstant(
           constantSystem.createString(new DartString.literal(value)));
     }

pkg/compiler/lib/src/compiler.dart

@@ -209,15 +209,6 @@ abstract class Compiler implements LibraryLoaderListener {
   Element loadLibraryFunction;
   Element functionApplyMethod;
 
-  /// The [int.fromEnvironment] constructor.
-  ConstructorElement intEnvironment;
-
-  /// The [bool.fromEnvironment] constructor.
-  ConstructorElement boolEnvironment;
-
-  /// The [String.fromEnvironment] constructor.
-  ConstructorElement stringEnvironment;
-
   // TODO(zarah): Remove this map and incorporate compile-time errors
   // in the model.
   /// Tracks elements with compile-time errors.
@@ -623,12 +614,6 @@ abstract class Compiler implements LibraryLoaderListener {
       mirrorSystemGetNameFunction = cls.lookupLocalMember('getName');
     } else if (mirrorsUsedClass == cls) {
       mirrorsUsedConstructor = cls.constructors.head;
-    } else if (coreClasses.intClass == cls) {
-      intEnvironment = cls.lookupConstructor(Identifiers.fromEnvironment);
-    } else if (coreClasses.stringClass == cls) {
-      stringEnvironment = cls.lookupConstructor(Identifiers.fromEnvironment);
-    } else if (coreClasses.boolClass == cls) {
-      boolEnvironment = cls.lookupConstructor(Identifiers.fromEnvironment);
     }
   }
 

pkg/compiler/lib/src/elements/common.dart

@@ -6,7 +6,7 @@
 
 library elements.common;
 
-import '../common/names.dart' show Names, Uris;
+import '../common/names.dart' show Identifiers, Names, Uris;
 import '../core_types.dart' show CoreClasses;
 import '../dart_types.dart' show DartType, InterfaceType, FunctionType;
 import '../util/util.dart' show Link;
@@ -607,3 +607,35 @@ abstract class AbstractFieldElementCommon implements AbstractFieldElement {
         setter != null && setter.isAbstract;
   }
 }
+
+abstract class ConstructorElementCommon implements ConstructorElement {
+  @override
+  bool get isFromEnvironmentConstructor {
+    return name == Identifiers.fromEnvironment &&
+        library.isDartCore &&
+        (enclosingClass.name == 'bool' ||
+            enclosingClass.name == 'int' ||
+            enclosingClass.name == 'String');
+  }
+
+  @override
+  bool get isIntFromEnvironmentConstructor {
+    return name == Identifiers.fromEnvironment &&
+        library.isDartCore &&
+        enclosingClass.name == 'int';
+  }
+
+  @override
+  bool get isBoolFromEnvironmentConstructor {
+    return name == Identifiers.fromEnvironment &&
+        library.isDartCore &&
+        enclosingClass.name == 'bool';
+  }
+
+  @override
+  bool get isStringFromEnvironmentConstructor {
+    return name == Identifiers.fromEnvironment &&
+        library.isDartCore &&
+        enclosingClass.name == 'String';
+  }
+}

pkg/compiler/lib/src/elements/elements.dart

@@ -1324,6 +1324,15 @@ abstract class ConstructorElement extends FunctionElement
   /// `int.fromEnvironment`, or `String.fromEnvironment`.
   bool get isFromEnvironmentConstructor;
 
+  /// `true` if this constructor is `int.fromEnvironment`.
+  bool get isIntFromEnvironmentConstructor;
+
+  /// `true` if this constructor is `bool.fromEnvironment`.
+  bool get isBoolFromEnvironmentConstructor;
+
+  /// `true` if this constructor is `String.fromEnvironment`.
+  bool get isStringFromEnvironmentConstructor;
+
   /// Use [enclosingClass] instead.
   @deprecated
   get enclosingElement;

pkg/compiler/lib/src/elements/modelx.dart

@@ -206,7 +206,9 @@ abstract class ElementX extends Element with ElementCommon {
   }
 }
 
-class ErroneousElementX extends ElementX implements ErroneousElement {
+class ErroneousElementX extends ElementX
+    with ConstructorElementCommon
+    implements ErroneousElement {
   final MessageKind messageKind;
   final Map messageArguments;
 
@@ -283,9 +285,6 @@ class ErroneousElementX extends ElementX implements ErroneousElement {
     throw new UnsupportedError("isEffectiveTargetMalformed");
   }
 
-  @override
-  bool get isFromEnvironmentConstructor => false;
-
   @override
   List<DartType> get typeVariables => unsupported();
 }
@@ -2167,21 +2166,13 @@ abstract class ConstantConstructorMixin implements ConstructorElement {
     }
   }
 
-  bool get isFromEnvironmentConstructor {
-    return name == 'fromEnvironment' &&
-        library.isDartCore &&
-        (enclosingClass.name == 'bool' ||
-            enclosingClass.name == 'int' ||
-            enclosingClass.name == 'String');
-  }
-
   /// Returns the empty list of type variables by default.
   @override
   List<DartType> get typeVariables => functionSignature.typeVariables;
 }
 
 abstract class ConstructorElementX extends FunctionElementX
-    with ConstantConstructorMixin
+    with ConstantConstructorMixin, ConstructorElementCommon
     implements ConstructorElement {
   bool isRedirectingGenerative = false;
 

pkg/compiler/lib/src/inferrer/type_graph_nodes.dart

@@ -494,15 +494,18 @@ class MemberTypeInformation extends ElementTypeInformation
     }
 
     Compiler compiler = inferrer.compiler;
-    if (element.declaration == compiler.intEnvironment) {
-      giveUp(inferrer);
-      return compiler.typesTask.intType.nullable();
-    } else if (element.declaration == compiler.boolEnvironment) {
-      giveUp(inferrer);
-      return compiler.typesTask.boolType.nullable();
-    } else if (element.declaration == compiler.stringEnvironment) {
-      giveUp(inferrer);
-      return compiler.typesTask.stringType.nullable();
+    if (element.isConstructor) {
+      ConstructorElement constructor = element;
+      if (constructor.isIntFromEnvironmentConstructor) {
+        giveUp(inferrer);
+        return compiler.typesTask.intType.nullable();
+      } else if (constructor.isBoolFromEnvironmentConstructor) {
+        giveUp(inferrer);
+        return compiler.typesTask.boolType.nullable();
+      } else if (constructor.isStringFromEnvironmentConstructor) {
+        giveUp(inferrer);
+        return compiler.typesTask.stringType.nullable();
+      }
     }
     return null;
   }

pkg/compiler/lib/src/serialization/modelz.dart

@@ -1157,7 +1157,8 @@ abstract class ConstructorElementZ extends DeserializedElementZ
         FunctionTypedElementMixin,
         ParametersMixin,
         TypedElementMixin,
-        MemberElementMixin
+        MemberElementMixin,
+        ConstructorElementCommon
     implements
         ConstructorElement,
         // TODO(johnniwinther): Sort out whether a constructor is a method.
@@ -1177,14 +1178,6 @@ abstract class ConstructorElementZ extends DeserializedElementZ
   @override
   bool get isExternal => _decoder.getBool(Key.IS_EXTERNAL);
 
-  bool get isFromEnvironmentConstructor {
-    return name == 'fromEnvironment' &&
-        library.isDartCore &&
-        (enclosingClass.name == 'bool' ||
-            enclosingClass.name == 'int' ||
-            enclosingClass.name == 'String');
-  }
-
   ConstantConstructor get constantConstructor {
     if (isConst && _constantConstructor == null) {
       ObjectDecoder data =
@@ -1412,6 +1405,15 @@ class ForwardingConstructorElementZ extends ElementZ
   @override
   bool get isFromEnvironmentConstructor => false;
 
+  @override
+  bool get isIntFromEnvironmentConstructor => false;
+
+  @override
+  bool get isBoolFromEnvironmentConstructor => false;
+
+  @override
+  bool get isStringFromEnvironmentConstructor => false;
+
   @override
   bool get isRedirectingFactory => false;
 

tests/compiler/dart2js/serialization/test_data.dart

@@ -367,6 +367,12 @@ main() {
 ''',
     'a.dart': '''
 void foo() {}
+''',
+  }),
+
+  const Test('fromEnvironment constants', const {
+    'main.dart': '''
+main() => const String.fromEnvironment("foo");
 ''',
   }),
 ];