Add tests for CoverageInstrumentationPass.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=111556170

src/com/google/javascript/jscomp/CoverageInstrumentationCallback.java

@@ -33,16 +33,17 @@
 class CoverageInstrumentationCallback extends
     NodeTraversal.AbstractPostOrderCallback {
 
+  private final AbstractCompiler compiler;
   private final Map<String, FileInstrumentationData> instrumentationData;
-
-  private CoverageReach reach;
+  private final CoverageReach reach;
 
   static final String ARRAY_NAME_PREFIX = "JSCompiler_lcov_data_";
 
-
   public CoverageInstrumentationCallback(
+      AbstractCompiler compiler,
       Map<String, FileInstrumentationData> instrumentationData,
       CoverageReach reach) {
+    this.compiler = compiler;
     this.instrumentationData = instrumentationData;
     this.reach = reach;
   }
@@ -61,8 +62,8 @@ private static String getFileName(NodeTraversal traversal) {
    * source filename of the AST node.
    */
   private String createArrayName(NodeTraversal traversal) {
-    return ARRAY_NAME_PREFIX +
-        CoverageUtil.createIdentifierFromText(getFileName(traversal));
+    return ARRAY_NAME_PREFIX
+        + CoverageUtil.createIdentifierFromText(getFileName(traversal));
   }
 
   /**
@@ -78,27 +79,25 @@ private String createArrayName(NodeTraversal traversal) {
    *  node is needed
    * @return an instrumentation node corresponding to the line number
    */
-  private Node newInstrumentationNode(NodeTraversal traversal, int lineNumber) {
-    String fileName = getFileName(traversal);
+  private Node newInstrumentationNode(NodeTraversal traversal, Node node) {
+    int lineNumber = node.getLineno();
     String arrayName = createArrayName(traversal);
 
     // Create instrumentation Node
-    //   arr[line] = true;
-    Node nameNode = IR.name(arrayName);
-    Node numNode = IR.number(lineNumber - 1);  // Make line number 0-based
-    Node getElemNode = IR.getelem(nameNode, numNode);
-    Node trueNode = IR.trueNode();
-    Node assignNode = IR.assign(getElemNode, trueNode);
-    Node exprNode = IR.exprResult(assignNode);
+    Node getElemNode = IR.getelem(
+        IR.name(arrayName),
+        IR.number(lineNumber - 1));  // Make line number 0-based
+    Node exprNode = IR.exprResult(IR.assign(getElemNode, IR.trueNode()));
 
     // Note line as instrumented
+    String fileName = getFileName(traversal);
     if (!instrumentationData.containsKey(fileName)) {
       instrumentationData.put(fileName,
                               new FileInstrumentationData(fileName, arrayName));
     }
     instrumentationData.get(fileName).setLineAsInstrumented(lineNumber);
 
-    return exprNode;
+    return exprNode.useSourceInfoIfMissingFromForTree(node);
   }
 
   /**
@@ -107,17 +106,15 @@ private Node newInstrumentationNode(NodeTraversal traversal, int lineNumber) {
    * "var arrayNameUsedInFile = [];"
    */
   private Node newArrayDeclarationNode(NodeTraversal traversal) {
-    Node arraylitNode = IR.arraylit();
-    Node nameNode = IR.name(createArrayName(traversal));
-    nameNode.addChildToFront(arraylitNode);
-    Node varNode = IR.var(nameNode);
-    return varNode;
+    return IR.var(
+        IR.name(createArrayName(traversal)),
+        IR.arraylit());
   }
 
   /**
    * @return a Node containing file specific setup logic.
    */
-  private Node newHeaderNode(NodeTraversal traversal) {
+  private Node newHeaderNode(NodeTraversal traversal, Node srcref) {
     String fileName = getFileName(traversal);
     String arrayName = createArrayName(traversal);
     FileInstrumentationData data = instrumentationData.get(fileName);
@@ -139,7 +136,7 @@ private Node newHeaderNode(NodeTraversal traversal) {
           IR.getprop(
               IR.name("JSCompiler_lcov_fileNames"),
               IR.string("push")),
-          IR.string(fileName))));
+          IR.string(fileName)))).useSourceInfoIfMissingFromForTree(srcref);
   }
 
   /**
@@ -153,8 +150,9 @@ public void visit(NodeTraversal traversal, Node node, Node parent) {
     if (node.isScript()) {
       String fileName = getFileName(traversal);
       if (instrumentationData.get(fileName) != null) {
-        node.addChildToFront(newHeaderNode(traversal));
+        node.addChildToFront(newHeaderNode(traversal, node));
       }
+      compiler.reportCodeChange();
       return;
     }
 
@@ -166,29 +164,33 @@ public void visit(NodeTraversal traversal, Node node, Node parent) {
 
     // Add instrumentation code just before a function block.
     // Similarly before other constructs: 'with', 'case', 'default', 'catch'
-    if (node.isFunction() ||
-        node.isWith() ||
-        node.isCase() ||
-        node.isDefaultCase() ||
-        node.isCatch()) {
+    if (node.isFunction()
+        || node.isWith()
+        || node.isCase()
+        || node.isDefaultCase()
+        || node.isCatch()) {
       Node codeBlock = node.getLastChild();
       codeBlock.addChildToFront(
-          newInstrumentationNode(traversal, node.getLineno()));
+          newInstrumentationNode(traversal, node));
+      compiler.reportCodeChange();
       return;
     }
 
     // Add instrumentation code as the first child of a 'try' block.
     if (node.isTry()) {
       Node firstChild = node.getFirstChild();
       firstChild.addChildToFront(
-          newInstrumentationNode(traversal, node.getLineno()));
+          newInstrumentationNode(traversal, node));
+      compiler.reportCodeChange();
       return;
     }
 
     // For any other statement, add instrumentation code just before it.
     if (parent != null && NodeUtil.isStatementBlock(parent)) {
       parent.addChildBefore(
-          newInstrumentationNode(traversal, node.getLineno()), node);
+          newInstrumentationNode(traversal, node),
+          node);
+      compiler.reportCodeChange();
       return;
     }
   }

src/com/google/javascript/jscomp/CoverageInstrumentationPass.java

@@ -39,10 +39,10 @@ class CoverageInstrumentationPass implements CompilerPass {
   private Map<String, FileInstrumentationData> instrumentationData;
   private CoverageReach reach;
 
-  private static final String JS_INSTRUMENTATION_EXTERNS_CODE =
-      "var JSCompiler_lcov_executedLines;\n" +
-      "var JSCompiler_lcov_instrumentedLines;\n" +
-      "var JSCompiler_lcov_fileNames;\n";
+  private static final String JS_INSTRUMENTATION_EXTERNS_CODE = ""
+      + "var JSCompiler_lcov_executedLines;\n"
+      + "var JSCompiler_lcov_instrumentedLines;\n"
+      + "var JSCompiler_lcov_fileNames;\n";
 
   public enum CoverageReach {
     ALL,
@@ -66,11 +66,11 @@ public CoverageInstrumentationPass(AbstractCompiler compiler,
    */
   private void addHeaderCode(Node script) {
     script.addChildToFront(
-        createConditionalVarDecl("JSCompiler_lcov_executedLines"));
+        createConditionalVarDecl("JSCompiler_lcov_executedLines", script));
     script.addChildToFront(
-        createConditionalVarDecl("JSCompiler_lcov_instrumentedLines"));
+        createConditionalVarDecl("JSCompiler_lcov_instrumentedLines", script));
     script.addChildToFront(
-        createConditionalVarDecl("JSCompiler_lcov_fileNames"));
+        createConditionalVarDecl("JSCompiler_lcov_fileNames", script));
   }
 
   /**
@@ -89,7 +89,8 @@ private Node getInstrumentationExternsNode() {
   public void process(Node externsNode, Node rootNode) {
     if (rootNode.hasChildren()) {
       NodeTraversal.traverseEs6(compiler, rootNode,
-          new CoverageInstrumentationCallback(instrumentationData, reach));
+          new CoverageInstrumentationCallback(
+              compiler, instrumentationData, reach));
 
       Node firstScript = rootNode.getFirstChild();
       Preconditions.checkState(firstScript.isScript());
@@ -99,7 +100,7 @@ public void process(Node externsNode, Node rootNode) {
     externsNode.addChildToBack(getInstrumentationExternsNode());
   }
 
-  private static Node createConditionalVarDecl(String name) {
+  private static Node createConditionalVarDecl(String name, Node srcref) {
     Node var = IR.var(
         IR.name(name),
         IR.or(
@@ -109,6 +110,6 @@ private static Node createConditionalVarDecl(String name) {
     JSDocInfoBuilder builder = new JSDocInfoBuilder(false);
     builder.recordSuppressions(ImmutableSet.of("duplicate"));
     var.setJSDocInfo(builder.build());
-    return var;
+    return var.useSourceInfoIfMissingFromForTree(srcref);
   }
 }

src/com/google/javascript/jscomp/FileInstrumentationData.java

@@ -82,9 +82,8 @@ String getInstrumentedLinesAsHexString() {
    * @param lineNumber the line number which was instrumented
    */
   void setLineAsInstrumented(int lineNumber) {
-    Preconditions.checkArgument(lineNumber > 0,
-                                "Expected non-zero positive integer as line " +
-                                "number.");
+    Preconditions.checkArgument(
+        lineNumber > 0, "Expected non-zero positive integer as line number: %s", lineNumber);
 
     // Map the 1-based line number to 0-based bit position
     instrumentedBits.set(lineNumber - 1);

test/com/google/javascript/jscomp/CoverageInstrumentationPassTest.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright 2016 The Closure Compiler Authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.javascript.jscomp;
+
+/**
+ * Tests for {@link CoverageInstrumentationPass}.
+ */
+public final class CoverageInstrumentationPassTest extends CompilerTestCase {
+  @Override
+  protected CompilerPass getProcessor(Compiler compiler) {
+    return new CoverageInstrumentationPass(compiler, CoverageInstrumentationPass.CoverageReach.ALL);
+  }
+
+  @Override
+  public void setUp() {
+//     enableLineNumberCheck(false);
+    allowExternsChanges(true);
+  }
+
+  public void testFunction() {
+    test(
+        "function f() { console.log('hi'); }",
+        LINE_JOINER.join(
+            "/** @suppress {duplicate} */",
+            "var JSCompiler_lcov_fileNames = JSCompiler_lcov_fileNames || [];",
+            "/** @suppress {duplicate} */",
+            "var JSCompiler_lcov_instrumentedLines = JSCompiler_lcov_instrumentedLines||[];",
+            "/** @suppress {duplicate} */",
+            "var JSCompiler_lcov_executedLines = JSCompiler_lcov_executedLines||[];",
+            "{",
+            "  var JSCompiler_lcov_data_testcode = [];",
+            "  JSCompiler_lcov_executedLines.push(JSCompiler_lcov_data_testcode);",
+            "  JSCompiler_lcov_instrumentedLines.push('01');",
+            "  JSCompiler_lcov_fileNames.push('testcode');",
+            "}",
+            "JSCompiler_lcov_data_testcode[0] = true;",
+            "/** @suppress {duplicate} */",
+            "var JSCompiler_lcov_fileNames = JSCompiler_lcov_fileNames||[];",
+            "JSCompiler_lcov_data_testcode[0] = true;",
+            "/** @suppress {duplicate} */",
+            "var JSCompiler_lcov_instrumentedLines = JSCompiler_lcov_instrumentedLines||[];",
+            "JSCompiler_lcov_data_testcode[0] = true;",
+            "/** @suppress {duplicate} */",
+            "var JSCompiler_lcov_executedLines = JSCompiler_lcov_executedLines||[];",
+            "JSCompiler_lcov_data_testcode[0] = true;",
+            "{",
+            "  JSCompiler_lcov_data_testcode[0] = true;",
+            "  var JSCompiler_lcov_data_testcode=[];",
+            "  JSCompiler_lcov_data_testcode[0] = true;",
+            "  JSCompiler_lcov_executedLines.push(JSCompiler_lcov_data_testcode);",
+            "  JSCompiler_lcov_data_testcode[0] = true;",
+            "  JSCompiler_lcov_instrumentedLines.push('01');",
+            "  JSCompiler_lcov_data_testcode[0] = true;",
+            "  JSCompiler_lcov_fileNames.push('testcode');",
+            "}",
+            "function f() {",
+            "  JSCompiler_lcov_data_testcode[0] = true;",
+            "  JSCompiler_lcov_data_testcode[0] = true;",
+            "  JSCompiler_lcov_data_testcode[0] = true;",
+            "  JSCompiler_lcov_data_testcode[0] = true;",
+            "  JSCompiler_lcov_data_testcode[0] = true;",
+            "  JSCompiler_lcov_data_testcode[0] = true;",
+            "  console.log('hi');",
+            "}"));
+  }
+}