Introduces native JsType.

This CL introduces native JsType based on prototype attribute
which will later be replaced by isNative attribute.

The patch doesn't handle static JsMethods/JsProperties, a follow
up patch will fix that.

Change-Id: Ibe5bf89978bb063ad86b003fe296acd02a362ff4
Review-Link: https://gwt-review.googlesource.com/#/c/13520/

dev/core/src/com/google/gwt/dev/javac/JSORestrictionsChecker.java

@@ -18,7 +18,6 @@
 import com.google.gwt.dev.jdt.SafeASTVisitor;
 import com.google.gwt.dev.util.InstalledHelpInfo;
 import com.google.gwt.dev.util.collect.Stack;
-import com.google.gwt.thirdparty.guava.common.base.Strings;
 
 import org.eclipse.jdt.core.compiler.CharOperation;
 import org.eclipse.jdt.internal.compiler.ast.ASTNode;
@@ -29,7 +28,6 @@
 import org.eclipse.jdt.internal.compiler.ast.MethodDeclaration;
 import org.eclipse.jdt.internal.compiler.ast.TypeDeclaration;
 import org.eclipse.jdt.internal.compiler.classfmt.ClassFileConstants;
-import org.eclipse.jdt.internal.compiler.lookup.AnnotationBinding;
 import org.eclipse.jdt.internal.compiler.lookup.BlockScope;
 import org.eclipse.jdt.internal.compiler.lookup.ClassScope;
 import org.eclipse.jdt.internal.compiler.lookup.CompilationUnitScope;
@@ -67,32 +65,28 @@ public class JSORestrictionsChecker {
       "@JsExport and @JsNoExport is not allowed at the same time.";
   public static final String ERR_JSEXPORT_ON_ENUMERATION =
       "@JsExport is not allowed on individual enumerations";
-  public static final String ERR_MUST_EXTEND_MAGIC_PROTOTYPE_CLASS =
-      "Classes implementing @JsType with a prototype must extend that interface's Prototype class";
-  public static final String ERR_CLASS_EXTENDS_MAGIC_PROTOTYPE_BUT_NO_PROTOTYPE_ATTRIBUTE =
-      "Classes implementing a @JsType without a prototype should not extend the Prototype class";
   public static final String ERR_CONSTRUCTOR_WITH_PARAMETERS =
       "Constructors must not have parameters in subclasses of JavaScriptObject";
-  public static final String ERR_INSTANCE_FIELD = "Instance fields cannot be used in subclasses of JavaScriptObject";
+  public static final String ERR_INSTANCE_FIELD =
+      "Instance fields cannot be used in subclasses of JavaScriptObject";
   public static final String ERR_INSTANCE_METHOD_NONFINAL =
       "Instance methods must be 'final' in non-final subclasses of JavaScriptObject";
-  public static final String ERR_IS_NONSTATIC_NESTED = "Nested classes must be 'static' if they extend JavaScriptObject";
+  public static final String ERR_IS_NONSTATIC_NESTED =
+      "Nested classes must be 'static' if they extend JavaScriptObject";
   public static final String ERR_NEW_JSO =
-      "'new' cannot be used to create instances of JavaScriptObject subclasses; instances must originate in JavaScript";
+      "'new' cannot be used to create instances of JavaScriptObject subclasses; "
+      + "instances must originate in JavaScript";
   public static final String ERR_NONEMPTY_CONSTRUCTOR =
       "Constructors must be totally empty in subclasses of JavaScriptObject";
   public static final String ERR_NONPROTECTED_CONSTRUCTOR =
       "Constructors must be 'protected' in subclasses of JavaScriptObject";
   public static final String ERR_OVERRIDDEN_METHOD =
       "Methods cannot be overridden in JavaScriptObject subclasses";
   public static final String JSO_CLASS = "com/google/gwt/core/client/JavaScriptObject";
-  public static final String ERR_FORGOT_TO_MAKE_PROTOTYPE_IMPL_JSTYPE = "@JsType subtype extends magic _Prototype class, but _Prototype class doesn't implement JsType";
-  public static final String ERR_JS_TYPE_WITH_PROTOTYPE_SET_NOT_ALLOWED_ON_CLASS_TYPES = "@JsType with prototype set not allowed on class types";
   public static final String ERR_JS_FUNCTION_ONLY_ALLOWED_ON_FUNCTIONAL_INTERFACE =
       "@JsFunction is only allowed on functional interface";
   public static final String ERR_JS_FUNCTION_CANNOT_HAVE_DEFAULT_METHODS =
       "JsFunction cannot have default methods";
-  static boolean LINT_MODE = false;
 
   private enum ClassState {
     NORMAL, JSO
@@ -247,18 +241,6 @@ private void checkJsFunction(TypeDeclaration type, TypeBinding typeBinding) {
       }
     }
 
-    private void checkJsType(TypeDeclaration type, TypeBinding typeBinding) {
-      ReferenceBinding binding = (ReferenceBinding) typeBinding;
-      if (binding.isClass()) {
-        AnnotationBinding jsinterfaceAnn = JdtUtil.getAnnotation(typeBinding,
-          JsInteropUtil.JSTYPE_CLASS);
-        String jsPrototype = JdtUtil.getAnnotationParameterString(jsinterfaceAnn, "prototype");
-        if (jsPrototype != null && !"".equals(jsPrototype)) {
-          errorOn(type, ERR_JS_TYPE_WITH_PROTOTYPE_SET_NOT_ALLOWED_ON_CLASS_TYPES);
-        }
-      }
-    }
-
     private void checkJsExport(MethodBinding mb) {
       if (JdtUtil.getAnnotation(mb, JsInteropUtil.JSEXPORT_CLASS) != null) {
         boolean isStatic = mb.isConstructor() || mb.isStatic();
@@ -294,14 +276,6 @@ private boolean isEnumConstant(FieldDeclaration fd) {
     private ClassState checkType(TypeDeclaration type) {
       SourceTypeBinding binding = type.binding;
       checkJsFunction(type, binding);
-      if (isJsType(type.binding)) {
-        checkJsType(type, type.binding);
-        return ClassState.NORMAL;
-      }
-
-      if (checkClassImplementingJsType(type)) {
-        return ClassState.NORMAL;
-      }
 
       if (!isJsoSubclass(binding)) {
         return ClassState.NORMAL;
@@ -332,91 +306,6 @@ private ClassState checkType(TypeDeclaration type) {
       return ClassState.JSO;
     }
 
-    private boolean checkClassImplementingJsType(TypeDeclaration type) {
-      ReferenceBinding jsInterface = findNearestJsTypeRecursive(type.binding);
-      if (jsInterface == null) {
-        return false;
-      }
-
-      AnnotationBinding jsinterfaceAnn = JdtUtil.getAnnotation(jsInterface,
-          JsInteropUtil.JSTYPE_CLASS);
-      String jsPrototype = JdtUtil.getAnnotationParameterString(jsinterfaceAnn, "prototype");
-      boolean shouldExtend = !Strings.isNullOrEmpty(jsPrototype);
-      checkClassExtendsMagicPrototype(type, jsInterface, shouldExtend);
-
-      // TODO(cromwellian) add multiple-inheritance checks when ambiguity in spec is resolved
-      return true;
-    }
-
-    private void checkClassExtendsMagicPrototype(TypeDeclaration type, ReferenceBinding jsInterface,
-        boolean shouldExtend) {
-      ReferenceBinding superClass = type.binding.superclass();
-      // if type is the _Prototype stub (implements JsType) exit
-      if (isMagicPrototype(type.binding, jsInterface)) {
-        return;
-      } else if (isMagicPrototypeStub(type)) {
-        errorOn(type, ERR_FORGOT_TO_MAKE_PROTOTYPE_IMPL_JSTYPE);
-      }
-
-      if (shouldExtend) {
-        // super class should be SomeInterface.Prototype, so enclosing type should match the jsInterface
-        if (LINT_MODE && (superClass == null || !isMagicPrototype(superClass, jsInterface))) {
-          errorOn(type, ERR_MUST_EXTEND_MAGIC_PROTOTYPE_CLASS);
-        }
-      } else {
-        if (superClass != null && isMagicPrototype(superClass, jsInterface)) {
-          errorOn(type, ERR_CLASS_EXTENDS_MAGIC_PROTOTYPE_BUT_NO_PROTOTYPE_ATTRIBUTE);
-        }
-      }
-    }
-
-    // Roughly parallels JProgram.isJsTypePrototype()
-    private boolean isMagicPrototype(ReferenceBinding type, ReferenceBinding jsInterface) {
-      if (isMagicPrototypeStub(type)) {
-        for (ReferenceBinding intf : type.superInterfaces()) {
-          if (intf == jsInterface) {
-            return true;
-          }
-        }
-      }
-      return false;
-    }
-
-    private boolean isMagicPrototypeStub(TypeDeclaration type) {
-      return isMagicPrototypeStub(type.binding);
-    }
-
-    private boolean isMagicPrototypeStub(ReferenceBinding binding) {
-      return JdtUtil.getAnnotation(binding, JsInteropUtil.JSTYPEPROTOTYPE_CLASS) != null;
-    }
-
-    /**
-     * Walks up chain of interfaces and superinterfaces to find the first one marked with @JsType.
-     */
-    private ReferenceBinding findNearestJsType(ReferenceBinding binding) {
-      if (isJsType(binding)) {
-        return binding;
-      }
-
-      for (ReferenceBinding intb : binding.superInterfaces()) {
-        ReferenceBinding checkSuperInt = findNearestJsType(intb);
-        if (checkSuperInt != null) {
-          return checkSuperInt;
-        }
-      }
-      return null;
-    }
-
-    private ReferenceBinding findNearestJsTypeRecursive(ReferenceBinding binding) {
-      ReferenceBinding nearest = findNearestJsType(binding);
-      if (nearest != null) {
-        return nearest;
-      } else if (binding.superclass() != null) {
-        return findNearestJsTypeRecursive(binding.superclass());
-      }
-      return null;
-    }
-
     private boolean areAllEnclosingClassesPublic() {
       for (SourceTypeBinding typeBinding : typeBindingStack) {
         if (!typeBinding.isPublic()) {
@@ -469,19 +358,6 @@ public static boolean isJso(TypeBinding typeBinding) {
     return false;
   }
 
-  /**
-   * Returns the first JsType annotation encountered traversing the type hierarchy upwards from the type.
-   */
-  private boolean isJsType(TypeBinding typeBinding) {
-
-    if (!(typeBinding instanceof ReferenceBinding) || !(typeBinding instanceof SourceTypeBinding)) {
-      return false;
-    }
-
-    AnnotationBinding jsInterface = JdtUtil.getAnnotation(typeBinding, JsInteropUtil.JSTYPE_CLASS);
-    return jsInterface != null;
-  }
-
   /**
    * Returns {@code true} if {@code typeBinding} is a subtype of
    * {@code JavaScriptObject}, but not {@code JavaScriptObject} itself.

dev/core/src/com/google/gwt/dev/javac/JsInteropUtil.java

@@ -24,7 +24,6 @@
 import com.google.gwt.thirdparty.guava.common.base.Strings;
 
 import org.eclipse.jdt.internal.compiler.ast.Annotation;
-import org.eclipse.jdt.internal.compiler.ast.TypeDeclaration;
 import org.eclipse.jdt.internal.compiler.lookup.AnnotationBinding;
 
 import java.beans.Introspector;
@@ -40,8 +39,6 @@ public final class JsInteropUtil {
   public static final String JSNOEXPORT_CLASS = "com.google.gwt.core.client.js.JsNoExport";
   public static final String JSPROPERTY_CLASS = "com.google.gwt.core.client.js.JsProperty";
   public static final String JSTYPE_CLASS = "com.google.gwt.core.client.js.JsType";
-  public static final String JSTYPEPROTOTYPE_CLASS =
-      "com.google.gwt.core.client.js.impl.PrototypeOfJsType";
 
   public static void maybeSetJsInteropProperties(JDeclaredType type, Annotation... annotations) {
     AnnotationBinding jsType = JdtUtil.getAnnotation(annotations, JSTYPE_CLASS);
@@ -106,10 +103,6 @@ private static String computeName(JMember member) {
     return member instanceof JConstructor ? "" : member.getName();
   }
 
-  public static boolean isJsPrototypeFlag(TypeDeclaration x) {
-    return JdtUtil.getAnnotation(x.annotations, JSTYPEPROTOTYPE_CLASS) != null;
-  }
-
   private static String maybeGetJsNamespace(Annotation[] annotations) {
     AnnotationBinding jsNamespace = JdtUtil.getAnnotation(annotations, JSNAMESPACE_CLASS);
     return JdtUtil.getAnnotationParameterString(jsNamespace, "value");

dev/core/src/com/google/gwt/dev/javac/JsniMethodCollector.java

@@ -187,10 +187,6 @@ public static JsFunction parseJsniFunction(AbstractMethodDeclaration method,
     int startPos = jsniCode.indexOf("/*-{");
     int endPos = jsniCode.lastIndexOf("}-*/");
     if (startPos < 0 && endPos < 0) {
-      reportJsniError(
-          info,
-          method,
-          "Native methods require a JavaScript implementation enclosed with /*-{ and }-*/");
       return null;
     }
     if (startPos < 0) {

dev/core/src/com/google/gwt/dev/jjs/ast/JClassType.java

@@ -42,7 +42,6 @@ private Object readResolve() {
   private final boolean isFinal;
   private boolean isJso;
   private JClassType superClass;
-  private boolean isJsPrototypeStub;
 
   public JClassType(SourceInfo info, String name, boolean isAbstract, boolean isFinal) {
     super(info, name);
@@ -113,6 +112,11 @@ public boolean isJsFunctionImplementation() {
     return false;
   }
 
+  @Override
+  public boolean canBeImplementedExternally() {
+    return isJsNative();
+  }
+
   /**
    * Sets this type's super class.
    */
@@ -125,14 +129,6 @@ public final void setSuperClass(JClassType superClass) {
     }
   }
 
-  public boolean isJsPrototypeStub() {
-    return isJsPrototypeStub;
-  }
-
-  public void setJsPrototypeStub(boolean isJsPrototype) {
-    this.isJsPrototypeStub = isJsPrototype;
-  }
-
   @Override
   public void traverse(JVisitor visitor, Context ctx) {
     if (visitor.visit(this, ctx)) {

dev/core/src/com/google/gwt/dev/jjs/ast/JDeclaredType.java

@@ -50,12 +50,12 @@
  */
 public abstract class JDeclaredType extends JReferenceType {
 
-  private String jsPrototype;
   private boolean isJsFunction;
   private boolean isJsType;
   private boolean isClassWideExport;
   private String jsNamespace = null;
   private String jsName = null;
+  private String jsPrototype;
 
   /**
    * The types of nested classes, https://docs.oracle.com/javase/tutorial/java/javaOO/nested.html
@@ -380,6 +380,11 @@ public String getJsPrototype() {
     return jsPrototype;
   }
 
+  @Override
+  public boolean isJsNative() {
+    return jsPrototype != null;
+  }
+
   /**
    * Returns this type's super class, or <code>null</code> if this type is
    * {@link Object} or an interface.

dev/core/src/com/google/gwt/dev/jjs/ast/JMethod.java

@@ -91,7 +91,7 @@ public boolean canBeCalledExternally() {
   }
 
   public boolean canBeImplementedExternally() {
-    return isJsFunctionMethod() || isJsInterfaceMethod();
+    return isJsNative() || isJsFunctionMethod() || isJsInterfaceMethod();
   }
 
   private boolean isJsInterfaceMethod() {
@@ -226,6 +226,10 @@ public boolean isOrOverridesJsFunctionMethod() {
     return false;
   }
 
+  public boolean isJsNative() {
+    return enclosingType != null && enclosingType.isJsNative();
+  }
+
   public void setSpecialization(List<JType> paramTypes, JType returnsType, String targetMethod) {
     this.specialization = new Specialization(paramTypes,
         returnsType == null ? this.getOriginalReturnType() : returnsType, targetMethod);

dev/core/src/com/google/gwt/dev/jjs/ast/JProgram.java

@@ -130,13 +130,6 @@ public String getclassName() {
     }
   }
 
-  /**
-   * Returns whether a class is a synthetic Prototype class generated by APT or user.
-   */
-  public boolean isJsTypePrototype(JDeclaredType classType) {
-    return classType instanceof JClassType && ((JClassType) classType).isJsPrototypeStub();
-  }
-
   private static final class TreeStatistics extends JVisitor {
     private int nodeCount = 0;
 
@@ -1177,20 +1170,6 @@ public boolean isStaticImpl(JMethod method) {
     return staticToInstanceMap.containsKey(method);
   }
 
-  public static JInterfaceType maybeGetJsTypeFromPrototype(JDeclaredType classType) {
-    if (classType == null) {
-      return null;
-    }
-    if (classType instanceof JClassType && ((JClassType) classType).isJsPrototypeStub()) {
-      for (JInterfaceType intf : classType.getImplements()) {
-        if (intf.isJsType() && intf.getJsPrototype() != null) {
-          return intf;
-        }
-      }
-    }
-    return null;
-  }
-
   /**
    * If the type is a JSO or an array of JSOs it returns cggcc.JavaScriptObject or an array of
    * cggcc.JavaScriptObject respectively; otherwise returns {@code type}.

dev/core/src/com/google/gwt/dev/jjs/ast/JType.java

@@ -77,6 +77,10 @@ public boolean isJsFunction() {
     return false;
   }
 
+  public boolean isJsNative() {
+    return false;
+  }
+
   public boolean canBeImplementedExternally() {
     return false;
   }