Generate all runtime files from dart.

lib/src/codegen/js_codegen.dart

Index: lib/src/codegen/js_codegen.dart
diff --git a/lib/src/codegen/js_codegen.dart b/lib/src/codegen/js_codegen.dart
index 0ff3baadbffb8904081d3144b30bb3d788b64e54..ffd51b990e2be43035873b6a9fa0a90638c22925 100644
--- a/lib/src/codegen/js_codegen.dart
+++ b/lib/src/codegen/js_codegen.dart
@@ -94,6 +94,9 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
   final _dartxVar = new JS.Identifier('dartx');
   final _exportsVar = new JS.TemporaryId('exports');
   final _runtimeLibVar = new JS.Identifier('dart');
+  final _utilsLibVar = new JS.TemporaryId('utils');
+  final _classesLibVar = new JS.TemporaryId('classes');
+  final _rttiLibVar = new JS.TemporaryId('rtti');
   final _namedArgTemp = new JS.TemporaryId('opts');
 
   final TypeProvider _types;
@@ -108,7 +111,7 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
   /// The default value of the module object. See [visitLibraryDirective].
   String _jsModuleValue;
 
-  bool _isDartUtils;
+  bool _isDartRuntime;
 
   Map<String, DartType> _objectMembers;
 
@@ -123,10 +126,24 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
     var src = context.sourceFactory.forUri('dart:_interceptors');
     var interceptors = context.computeLibraryElement(src);
     _jsArray = interceptors.getType('JSArray');
-    _isDartUtils = currentLibrary.source.uri.toString() == 'dart:_utils';
+
+    _isDartRuntime = _runtimeLibUris.contains(_getLibUri(currentLibrary));
 
     _objectMembers = getObjectMemberMap(types);
   }
+  String _getLibUri(LibraryElement lib) => lib.source.uri.toString();
+
+  static final _runtimeLibUris = new Set<String>.from([
+    'dart:_utils',
+    'dart:_runtime',
+    'dart:_operations',
+    'dart:_errors',
+    'dart:_classes',
+    'dart:_generators',
+    'dart:_operations',
+    'dart:_types',
+    'dart:_rtti'
+  ]);
 
   TypeProvider get types => rules.provider;
 
@@ -196,39 +213,51 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
     // TODO(jmesserly): it would be great to run the renamer on the body,
     // then figure out if we really need each of these parameters.
     // See ES6 modules: https://github.com/dart-lang/dev_compiler/issues/34
-    var params = [_exportsVar, _runtimeLibVar];
-    var processImport =
-        (LibraryElement library, JS.TemporaryId temp, List list) {
-      params.add(temp);
-      list.add(js.string(compiler.getModuleName(library.source.uri), "'"));
-    };
+    var params = [_exportsVar];
+    var lazyParams = [];
 
-    var needsDartRuntime = !_isDartUtils;
+    var libUri = _getLibUri(currentLibrary);
 
     var imports = <JS.Expression>[];
+    var lazyImports = <JS.Expression>[];
     var moduleStatements = <JS.Statement>[];
-    if (needsDartRuntime) {
-      imports.add(js.string('dart/_runtime'));
+
+    addImport(String name, JS.Expression libVar, {bool eager: true}) {
+      (eager ? imports : lazyImports).add(js.string(name, "'"));
+      (eager ? params : lazyParams).add(libVar);
+    }
+
+    if (!_isDartRuntime) {
+      addImport('dart/_runtime', _runtimeLibVar);
 
       var dartxImport =
           js.statement("let # = #.dartx;", [_dartxVar, _runtimeLibVar]);
       moduleStatements.add(dartxImport);
+    } else {
+      if (libUri == 'dart:_generators') {
+        addImport('dart/_classes', _classesLibVar);
+      }
     }
     moduleStatements.addAll(_moduleItems);
 
-    _imports.forEach((library, temp) {
-      if (_loader.libraryIsLoaded(library)) {
-        processImport(library, temp, imports);
-      }
-    });
+    bool shouldImportEagerly(lib) {
+      var otherLibUri = _getLibUri(lib);
+      if (otherLibUri == 'dart:_utils') return true;
+      if (libUri == 'dart:_types' && otherLibUri == 'dart:_rtti') return true;
+      if (libUri == 'dart:_runtime') return otherLibUri != 'dart:_js_helper';
+      return !_isDartRuntime && _loader.libraryIsLoaded(lib);
+    }
 
-    var lazyImports = <JS.Expression>[];
-    _imports.forEach((library, temp) {
-      if (!_loader.libraryIsLoaded(library)) {
-        processImport(library, temp, lazyImports);
-      }
+    var importsEagerness = new Map<LibraryElement, bool>.fromIterable(
+        _imports.keys, value: shouldImportEagerly);
+
+    _imports.forEach((LibraryElement lib, JS.TemporaryId temp) {
+      bool eager = importsEagerness[lib];
+      addImport(compiler.getModuleName(lib.source.uri), temp, eager: eager);
     });
 
+    params.addAll(lazyParams);
+
     var module =
         js.call("function(#) { 'use strict'; #; }", [params, moduleStatements]);
 
@@ -264,9 +293,12 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
   void visitLibraryDirective(LibraryDirective node) {
     assert(_jsModuleValue == null);
 
-    var jsName = findAnnotation(node.element, isJSAnnotation);
-    _jsModuleValue =
-        getConstantField(jsName, 'name', types.stringType)?.toStringValue();
+    _jsModuleValue = _getJsName(node.element);
+  }
+
+  String _getJsName(Element e) {
+    var jsName = findAnnotation(e, isJSAnnotation);
+    return getConstantField(jsName, 'name', types.stringType)?.toStringValue();
   }
 
   @override
@@ -294,8 +326,12 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
       var hide = node.combinators.firstWhere((c) => c is HideCombinator,
           orElse: () => null) as HideCombinator;
       if (show != null) {
+        var singleName = _getJsName(node.element);
+        if (singleName != null && show.shownNames.length != 1) {
+          throw new StateError('Cannot set js name on more than one name');
+        }
         shownNames.addAll(show.shownNames
-            .map((i) => i.name)
+            .map((i) => singleName ?? i.name)
             .where((s) => !currentLibNames.containsKey(s))
             .map((s) => js.string(s, "'")));
       }
@@ -305,7 +341,10 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
       args.add(new JS.ArrayInitializer(shownNames));
       args.add(new JS.ArrayInitializer(hiddenNames));
     }
-    _moduleItems.add(js.statement('dart.export_(#);', [args]));
+
+    // When we compile _runtime.js, we need to source export_ from _utils.js:
+    _moduleItems.add(js.statement('#.export(#);',
+        [_isDartRuntime ? _utilsLibVar : _runtimeLibVar, args]));
   }
 
   JS.Identifier _initSymbol(JS.Identifier id) {
@@ -579,10 +618,14 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
     var genericName = '$name\$';
     var typeParams = type.typeParameters.map((p) => p.name);
     if (isPublic(name)) _exports.add(genericName);
-    return js.statement('const # = dart.generic(function(#) { #; return #; });',
-        [genericName, typeParams, body, name]);
+
+    return js.statement('const # = #(function(#) { #; return #; });',
+        [genericName, _dartGeneric, typeParams, body, name]);
   }
 
+  get _dartGeneric =>
+      js.call('#.generic', [_isDartRuntime ? _classesLibVar : _runtimeLibVar]);
+
   final _hasDeferredSupertype = new HashSet<ClassElement>();
 
   bool _deferIfNeeded(DartType type, ClassElement current) {
@@ -832,7 +875,7 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
       if (!sigFields.isEmpty || extensions.isNotEmpty) {
         var sig = new JS.ObjectInitializer(sigFields);
         var classExpr = new JS.Identifier(name);
-        body.add(js.statement('dart.setSignature(#, #);', [classExpr, sig]));
+        body.add(js.statement('#(#, #);', [_dartSetSignature, classExpr, sig]));
       }
     }
 
@@ -862,6 +905,9 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
     return _statement(body);
   }
 
+  get _dartSetSignature =>
+      js.call('#.setSignature', [_isDartRuntime ? _classesLibVar : _runtimeLibVar]);
+
   List<ExecutableElement> _extensionsToImplement(ClassElement element) {
     var members = <ExecutableElement>[];
     if (_extensionTypes.contains(element)) return members;
@@ -1302,15 +1348,14 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
     var body = <JS.Statement>[];
     _flushLibraryProperties(body);
 
-    var name = node.name.name;
+    var name = _getJsName(node.element) ?? node.name.name;
 
     var fn = _visit(node.functionExpression);
-    bool needsTagging = true;
+    bool needsTagging = !_isDartRuntime;
 
     if (currentLibrary.source.isInSystemLibrary &&
         _isInlineJSFunction(node.functionExpression)) {
       fn = _simplifyPassThroughArrowFunCallBody(fn);
-      needsTagging = !_isDartUtils;
     }
 
     var id = new JS.Identifier(name);
@@ -1406,16 +1451,18 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
           type.optionalParameterTypes.isEmpty &&
           type.namedParameterTypes.isEmpty &&
           type.normalParameterTypes.every((t) => t.isDynamic)) {
-        return js.call('dart.fn(#)', [clos]);
+        return js.call('#(#)', [_dartFn, clos]);
       }
       if (lazy) {
-        return js.call('dart.fn(#, () => #)', [clos, _emitFunctionRTTI(type)]);
+        return js.call('#(#, () => #)', [_dartFn, clos, _emitFunctionRTTI(type)]);
       }
-      return js.call('dart.fn(#, #)', [clos, _emitFunctionTypeParts(type)]);
+      return js.call('#(#, #)', [_dartFn, clos, _emitFunctionTypeParts(type)]);
     }
     throw 'Function has non function type: $type';
   }
 
+  get _dartFn => js.call('#.fn', _isDartRuntime ? _rttiLibVar : _runtimeLibVar);
+
   @override
   JS.Expression visitFunctionExpression(FunctionExpression node) {
     var params = _visit(node.parameters) as List<JS.Parameter>;
@@ -1566,7 +1613,7 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
 
     _loader.declareBeforeUse(element);
 
-    var name = element.name;
+    var name = _getJsName(element) ?? element.name;
 
     // type literal
     if (element is ClassElement ||
@@ -1578,7 +1625,7 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
 
     // library member
     if (element.enclosingElement is CompilationUnitElement) {
-      return _maybeQualifiedName(element);
+      return _maybeQualifiedName(element, name);
     }
 
     // Unqualified class member. This could mean implicit-this, or implicit
@@ -1881,11 +1928,30 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
       new JS.Block(_visitList(node.statements) as List<JS.Statement>,
           isScope: true);
 
+  /// Return the type constructor `_foolib.Bar$` given `Bar` from lib `_foolib`.
+  JS.Expression _emitGenericTypeConstructor(Expression typeExpression) {
+    var ref = _visit(typeExpression);
+    if (ref is JS.PropertyAccess) {
+      var name = (ref.selector as JS.LiteralString).valueWithoutQuotes;
+      return new JS.PropertyAccess(
+          ref.receiver, new JS.LiteralString("'$name\$'"));
+    } else if (ref is JS.MaybeQualifiedId) {
+      var name = (ref.name as JS.Identifier).name;
+      return new JS.PropertyAccess(
+          ref.qualifier, new JS.Identifier('$name\$'));
+    } else {
+      throw new ArgumentError('Invalid type ref: $ref (${ref?.runtimeType})');
+    }
+  }
+
   @override
   visitMethodInvocation(MethodInvocation node) {
     if (node.operator != null && node.operator.lexeme == '?.') {
       return _emitNullSafe(node);
     }
+    if (isGenericTypeConstructorInvocation(node)) {
+      return _emitGenericTypeConstructor(node.argumentList.arguments.single);
+    }
 
     var target = _getTarget(node);
     var result = _emitForeignJS(node);
@@ -2211,7 +2277,8 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
     var isJSTopLevel = field.isFinal && _isFinalJSDecl(field);
     if (isJSTopLevel) eagerInit = true;
 
-    var fieldName = field.name.name;
+    var fieldName = _getJsName(element) ?? field.name.name;
+
     if ((field.isConst && eagerInit && element is TopLevelVariableElement) ||
         isJSTopLevel) {
       // constant fields don't change, so we can generate them as `let`
@@ -2847,7 +2914,7 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
       } else if (_requiresStaticDispatch(target, memberId.name)) {
         var type = member.type;
         var clos = js.call('dart.#.bind(#)', [name, _visit(target)]);
-        return js.call('dart.fn(#, #)', [clos, _emitFunctionTypeParts(type)]);
+        return js.call('#(#, #)', [_dartFn, clos, _emitFunctionTypeParts(type)]);
       }
       code = 'dart.bind(#, #)';
     } else if (_requiresStaticDispatch(target, memberId.name)) {
@@ -3416,8 +3483,13 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ClosureAnnotator {
   /// declaration) as it doesn't have any meaningful rules enforced.
   JS.Identifier _libraryName(LibraryElement library) {
     if (library == currentLibrary) return _exportsVar;
-    return _imports.putIfAbsent(
-        library, () => new JS.TemporaryId(jsLibraryName(library)));
+    return _imports.putIfAbsent(library, () {
+      var name = library.name;
+      if (name == 'dart._utils') return _utilsLibVar;
+      else if (name == 'dart._classes') return _classesLibVar;
+      else if (name == 'dart._rtti') return _rttiLibVar;
+      else return new JS.TemporaryId(jsLibraryName(library));
+    });
   }
 
   DartType getStaticType(Expression e) => rules.getStaticType(e);