Remove backends.

compiler/java/com/google/dart/compiler/backend/js/Cloner.java

Index: compiler/java/com/google/dart/compiler/backend/js/Cloner.java
diff --git a/compiler/java/com/google/dart/compiler/backend/js/Cloner.java b/compiler/java/com/google/dart/compiler/backend/js/Cloner.java
deleted file mode 100644
index b0dd804410ed9d58c99ed253170bed43a7c8256e..0000000000000000000000000000000000000000
--- a/compiler/java/com/google/dart/compiler/backend/js/Cloner.java
+++ /dev/null
@@ -1,253 +0,0 @@
-// Copyright 2011, the Dart project authors. All rights reserved.
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//  * Redistributions of source code must retain the above copyright
-//    notice, this list of conditions and the following disclaimer.
-//  * Redistributions in binary form must reproduce the above
-//    copyright notice, this list of conditions and the following
-//    disclaimer in the documentation and/or other materials provided
-//    with the distribution.
-//  * Neither the name of Google Inc. nor the names of its
-//    contributors may be used to endorse or promote products derived
-//    from this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-package com.google.dart.compiler.backend.js;
-
-import com.google.dart.compiler.InternalCompilerException;
-import com.google.dart.compiler.backend.js.ast.JsArrayAccess;
-import com.google.dart.compiler.backend.js.ast.JsArrayLiteral;
-import com.google.dart.compiler.backend.js.ast.JsBinaryOperation;
-import com.google.dart.compiler.backend.js.ast.JsBooleanLiteral;
-import com.google.dart.compiler.backend.js.ast.JsConditional;
-import com.google.dart.compiler.backend.js.ast.JsContext;
-import com.google.dart.compiler.backend.js.ast.JsExpression;
-import com.google.dart.compiler.backend.js.ast.JsFunction;
-import com.google.dart.compiler.backend.js.ast.JsInvocation;
-import com.google.dart.compiler.backend.js.ast.JsName;
-import com.google.dart.compiler.backend.js.ast.JsNameRef;
-import com.google.dart.compiler.backend.js.ast.JsNew;
-import com.google.dart.compiler.backend.js.ast.JsNullLiteral;
-import com.google.dart.compiler.backend.js.ast.JsNumberLiteral;
-import com.google.dart.compiler.backend.js.ast.JsObjectLiteral;
-import com.google.dart.compiler.backend.js.ast.JsPostfixOperation;
-import com.google.dart.compiler.backend.js.ast.JsPrefixOperation;
-import com.google.dart.compiler.backend.js.ast.JsPropertyInitializer;
-import com.google.dart.compiler.backend.js.ast.JsRegExp;
-import com.google.dart.compiler.backend.js.ast.JsStringLiteral;
-import com.google.dart.compiler.backend.js.ast.JsThisRef;
-import com.google.dart.compiler.backend.js.ast.JsVisitor;
-
-import java.util.ArrayList;
-import java.util.List;
-import java.util.Stack;
-
-/**
- * Implements actual cloning logic. We rely on the JsExpressions to provide
- * traversal logic. The {@link #stack} field is used to accumulate
- * already-cloned JsExpression instances. One gotcha that falls out of this is
- * that argument lists are on the stack in reverse order, so lists should be
- * constructed via inserts, rather than appends.
- */
-public class Cloner extends JsVisitor {
-  protected final Stack<JsExpression> stack = new Stack<JsExpression>();
-  private boolean successful = true;
-
-  /**
-   * @param expression
-   * @return Return a clone of the expression tree
-   */
-  public static JsExpression clone(JsExpression expression) {
-    Cloner c = new Cloner();
-    c.accept(expression);
-    return c.getExpression();
-  }
-
-  @Override
-  public void endVisit(JsArrayAccess x, JsContext ctx) {
-    JsArrayAccess newExpression = new JsArrayAccess();
-    newExpression.setIndexExpr(stack.pop());
-    newExpression.setArrayExpr(stack.pop());
-    stack.push(newExpression);
-  }
-
-  @Override
-  public void endVisit(JsArrayLiteral x, JsContext ctx) {
-    JsArrayLiteral toReturn = new JsArrayLiteral();
-    List<JsExpression> expressions = toReturn.getExpressions();
-    int size = x.getExpressions().size();
-    while (size-- > 0) {
-      expressions.add(0, stack.pop());
-    }
-    stack.push(toReturn);
-  }
-
-  @Override
-  public void endVisit(JsBinaryOperation x, JsContext ctx) {
-    JsBinaryOperation toReturn = new JsBinaryOperation(x.getOperator());
-    toReturn.setArg2(stack.pop());
-    toReturn.setArg1(stack.pop());
-    stack.push(toReturn);
-  }
-
-  @Override
-  public void endVisit(JsBooleanLiteral x, JsContext ctx) {
-    stack.push(x);
-  }
-
-  @Override
-  public void endVisit(JsConditional x, JsContext ctx) {
-    JsConditional toReturn = new JsConditional();
-    toReturn.setElseExpression(stack.pop());
-    toReturn.setThenExpression(stack.pop());
-    toReturn.setTestExpression(stack.pop());
-    stack.push(toReturn);
-  }
-
-  /**
-   * The only functions that would get be visited are those being used as
-   * first-class objects.
-   */
-  @Override
-  public void endVisit(JsFunction x, JsContext ctx) {
-    // Set a flag to indicate that we cannot continue, and push a null so
-    // we don't run out of elements on the stack.
-    successful = false;
-    stack.push(null);
-  }
-
-  /**
-   * Cloning the invocation allows us to modify it without damaging other call
-   * sites.
-   */
-  @Override
-  public void endVisit(JsInvocation x, JsContext ctx) {
-    JsInvocation toReturn = new JsInvocation();
-    List<JsExpression> params = toReturn.getArguments();
-    int size = x.getArguments().size();
-    while (size-- > 0) {
-      params.add(0, stack.pop());
-    }
-    toReturn.setQualifier(stack.pop());
-    stack.push(toReturn);
-  }
-
-  /**
-   * Do a deep clone of a JsNameRef. Because JsNameRef chains are shared
-   * throughout the AST, you can't just go and change their qualifiers when
-   * re-writing an invocation.
-   */
-  @Override
-  public void endVisit(JsNameRef x, JsContext ctx) {
-    JsNameRef toReturn;
-    JsName name = x.getName();
-    if (name != null) {
-      toReturn = new JsNameRef(name);
-    } else {
-      toReturn = new JsNameRef(x.getIdent());
-    }
-
-    if (x.getQualifier() != null) {
-      toReturn.setQualifier(stack.pop());
-    }
-    stack.push(toReturn);
-  }
-
-  @Override
-  public void endVisit(JsNew x, JsContext ctx) {
-    int size = x.getArguments().size();
-    List<JsExpression> arguments = new ArrayList<JsExpression>(size);
-    while (size-- > 0) {
-      arguments.add(0, stack.pop());
-    }
-    JsNew toReturn = new JsNew(stack.pop());
-    toReturn.getArguments().addAll(arguments);
-    stack.push(toReturn);
-  }
-
-  @Override
-  public void endVisit(JsNullLiteral x, JsContext ctx) {
-    stack.push(x);
-  }
-
-  @Override
-  public void endVisit(JsNumberLiteral x, JsContext ctx) {
-    stack.push(x);
-  }
-
-  @Override
-  public void endVisit(JsObjectLiteral x, JsContext ctx) {
-    JsObjectLiteral toReturn = new JsObjectLiteral();
-    List<JsPropertyInitializer> inits = toReturn.getPropertyInitializers();
-
-    int size = x.getPropertyInitializers().size();
-    while (size-- > 0) {
-      /*
-       * JsPropertyInitializers are the only non-JsExpression objects that we
-       * care about, so we just go ahead and create the objects in the loop,
-       * rather than expecting it to be on the stack and having to perform
-       * narrowing casts at all stack.pop() invocations.
-       */
-      JsPropertyInitializer newInit = new JsPropertyInitializer();
-      newInit.setValueExpr(stack.pop());
-      newInit.setLabelExpr(stack.pop());
-
-      inits.add(0, newInit);
-    }
-    stack.push(toReturn);
-  }
-
-  @Override
-  public void endVisit(JsPostfixOperation x, JsContext ctx) {
-    JsPostfixOperation toReturn = new JsPostfixOperation(x.getOperator());
-    toReturn.setArg(stack.pop());
-    stack.push(toReturn);
-  }
-
-  @Override
-  public void endVisit(JsPrefixOperation x, JsContext ctx) {
-    JsPrefixOperation toReturn = new JsPrefixOperation(x.getOperator());
-    toReturn.setArg(stack.pop());
-    stack.push(toReturn);
-  }
-
-  @Override
-  public void endVisit(JsRegExp x, JsContext ctx) {
-    stack.push(x);
-  }
-
-  @Override
-  public void endVisit(JsStringLiteral x, JsContext ctx) {
-    stack.push(x);
-  }
-
-  @Override
-  public void endVisit(JsThisRef x, JsContext ctx) {
-    stack.push(new JsThisRef());
-  }
-
-  public JsExpression getExpression() {
-    return (successful && checkStack()) ? stack.peek() : null;
-  }
-
-  private boolean checkStack() {
-    if (stack.size() > 1) {
-      throw new InternalCompilerException("Too many expressions on stack");
-    }
-
-    return stack.size() == 1;
-  }
-}
-