Convert into/from => function syntax

editor/tools/plugins/com.google.dart.tools.ui/src/com/google/dart/tools/ui/internal/text/correction/QuickAssistProcessor.java

Index: editor/tools/plugins/com.google.dart.tools.ui/src/com/google/dart/tools/ui/internal/text/correction/QuickAssistProcessor.java
diff --git a/editor/tools/plugins/com.google.dart.tools.ui/src/com/google/dart/tools/ui/internal/text/correction/QuickAssistProcessor.java b/editor/tools/plugins/com.google.dart.tools.ui/src/com/google/dart/tools/ui/internal/text/correction/QuickAssistProcessor.java
index a3e5b70028c6ecb01409a08e538c65372cbaa378..1bc8065aef69be2c788c41ba3fbe29ebc21da9f7 100644
--- a/editor/tools/plugins/com.google.dart.tools.ui/src/com/google/dart/tools/ui/internal/text/correction/QuickAssistProcessor.java
+++ b/editor/tools/plugins/com.google.dart.tools.ui/src/com/google/dart/tools/ui/internal/text/correction/QuickAssistProcessor.java
@@ -13,6 +13,10 @@
  */
 package com.google.dart.tools.ui.internal.text.correction;
 
+import static com.google.dart.tools.core.dom.PropertyDescriptorHelper.DART_BINARY_EXPRESSION_LEFT_OPERAND;
+import static com.google.dart.tools.core.dom.PropertyDescriptorHelper.DART_VARIABLE_NAME;
+import static com.google.dart.tools.core.dom.PropertyDescriptorHelper.getLocationInParent;
+
 import com.google.common.collect.Lists;
 import com.google.dart.compiler.ast.DartBinaryExpression;
 import com.google.dart.compiler.ast.DartBlock;
@@ -20,8 +24,12 @@ import com.google.dart.compiler.ast.DartExprStmt;
 import com.google.dart.compiler.ast.DartExpression;
 import com.google.dart.compiler.ast.DartField;
 import com.google.dart.compiler.ast.DartFieldDefinition;
+import com.google.dart.compiler.ast.DartFunction;
 import com.google.dart.compiler.ast.DartIdentifier;
+import com.google.dart.compiler.ast.DartMethodDefinition;
 import com.google.dart.compiler.ast.DartNode;
+import com.google.dart.compiler.ast.DartReturnBlock;
+import com.google.dart.compiler.ast.DartReturnStatement;
 import com.google.dart.compiler.ast.DartStatement;
 import com.google.dart.compiler.ast.DartUnit;
 import com.google.dart.compiler.ast.DartVariable;
@@ -46,10 +54,6 @@ import com.google.dart.tools.ui.text.dart.IInvocationContext;
 import com.google.dart.tools.ui.text.dart.IProblemLocation;
 import com.google.dart.tools.ui.text.dart.IQuickAssistProcessor;
 
-import static com.google.dart.tools.core.dom.PropertyDescriptorHelper.DART_BINARY_EXPRESSION_LEFT_OPERAND;
-import static com.google.dart.tools.core.dom.PropertyDescriptorHelper.DART_VARIABLE_NAME;
-import static com.google.dart.tools.core.dom.PropertyDescriptorHelper.getLocationInParent;
-
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.swt.graphics.Image;
 import org.eclipse.text.edits.MultiTextEdit;
@@ -193,6 +197,62 @@ public class QuickAssistProcessor implements IQuickAssistProcessor {
     return true;
   }
 
+  boolean addProposal_convertToBlockFunctionBody() throws Exception {
+    // prepare enclosing function
+    DartFunction function = getEnclosingFunctionOrMethodFunction();
+    if (function == null) {
+      return false;
+    }
+    // prepare return statement
+    if (!(function.getBody() instanceof DartReturnBlock)) {
+      return false;
+    }
+    DartReturnBlock returnBlock = (DartReturnBlock) function.getBody();
+    DartExpression returnValue = returnBlock.getValue();
+    // add change
+    String eol = utils.getEndOfLine();
+    String prefix = utils.getNodePrefix(function) + utils.getIndent(1);
+    String newBodySource = "{" + eol + prefix + "return " + getSource(returnValue) + ";" + eol
+        + "}";
+    textEdits.add(createReplaceEdit(SourceRangeFactory.create(returnBlock), newBodySource));
+    // add proposal
+    addUnitCorrectionProposal(
+        CorrectionMessages.QuickAssistProcessor_convertToBlockBody,
+        DartPluginImages.get(DartPluginImages.IMG_CORRECTION_CHANGE));
+    return true;
+  }
+
+  boolean addProposal_convertToExpressionFunctionBody() throws Exception {
+    // prepare enclosing function
+    DartFunction function = getEnclosingFunctionOrMethodFunction();
+    if (function == null) {
+      return false;
+    }
+    // prepare return statement
+    DartBlock body = function.getBody();
+    List<DartStatement> statements = body.getStatements();
+    if (statements.size() != 1) {
+      return false;
+    }
+    if (!(statements.get(0) instanceof DartReturnStatement)) {
+      return false;
+    }
+    DartReturnStatement returnStatement = (DartReturnStatement) statements.get(0);
+    // prepare returned value
+    DartExpression returnValue = returnStatement.getValue();
+    if (returnValue == null) {
+      return false;
+    }
+    // add change
+    String newBodySource = "=> " + getSource(returnValue) + ";";
+    textEdits.add(createReplaceEdit(SourceRangeFactory.create(body), newBodySource));
+    // add proposal
+    addUnitCorrectionProposal(
+        CorrectionMessages.QuickAssistProcessor_convertToExpressionBody,
+        DartPluginImages.get(DartPluginImages.IMG_CORRECTION_CHANGE));
+    return true;
+  }
+
   boolean addProposal_exchangeOperands() throws Exception {
     // check that user invokes quick assist on binary expression
     if (!(node instanceof DartBinaryExpression)) {
@@ -364,6 +424,29 @@ public class QuickAssistProcessor implements IQuickAssistProcessor {
   }
 
   /**
+   * @return the enclosing {@link DartFunction} for {@link #node}, or is part of enclosing
+   *         {@link DartMethodDefinition}. May be <code>null</code>.
+   */
+  private DartFunction getEnclosingFunctionOrMethodFunction() {
+    DartFunction function = ASTNodes.getAncestor(node, DartFunction.class);
+    if (function == null) {
+      DartMethodDefinition method = ASTNodes.getAncestor(node, DartMethodDefinition.class);
+      if (method != null) {
+        function = method.getFunction();
+      }
+    }
+    return function;
+  }
+
+  /**
+   * @return the part of {@link #unit} source.
+   */
+  private String getSource(HasSourceInfo hasSourceInfo) throws Exception {
+    SourceRange range = SourceRangeFactory.create(hasSourceInfo);
+    return getSource(range);
+  }
+
+  /**
    * @return the part of {@link #unit} source.
    */
   private String getSource(int offset, int length) throws Exception {