Introduces Util.$getDefine for J2CL to get @define properties.

------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=123171684
google · May 25, 2016 · 467c5b7 · 467c5b7
1 parent 016769e
commit 467c5b7
Show file tree

Hide file tree

Showing 3 changed files with 95 additions and 16 deletions.
diff --git a/src/com/google/javascript/jscomp/J2clPass.java b/src/com/google/javascript/jscomp/J2clPass.java
@@ -21,6 +21,7 @@
 import com.google.javascript.jscomp.FunctionInjector.Reference;
 import com.google.javascript.jscomp.NodeTraversal.AbstractPostOrderCallback;
 import com.google.javascript.jscomp.NodeTraversal.Callback;
+import com.google.javascript.rhino.IR;
 import com.google.javascript.rhino.Node;
 
 import java.util.HashMap;
@@ -29,20 +30,62 @@
 
 /**
  * Rewrites/inlines some J2CL constructs to be more optimizable.
- *
- * <p>Inlines Arrays.$create(), Arrays.$init(), Arrays.$instanceIsOfType(), Arrays.$castTo() and
- * Casts.to() so that all references to Object.$isInstance() functions will be fully qualified
- * and easy to strip.
- *
- * <p>Inlines all Interface.$markImplementor(FooClass) metaclass calls so that FooClass and others
- * like it are not unnecessarily retained and so that static analysis of interface instanceof calls
- * becomes possible.
  */
 public class J2clPass implements CompilerPass {
   private static final String ALL_CLASS_FILE_NAMES = "*";
   private final AbstractCompiler compiler;
   private final Supplier<String> safeNameIdSupplier;
 
+  private class GetDefineRewriter extends AbstractPostOrderCallback {
+    private Set<String> defines;
+
+    GetDefineRewriter(Set<String> defines) {
+      this.defines = defines;
+    }
+
+    @Override
+    public void visit(NodeTraversal t, Node n, Node parent) {
+      if (isUtilGetDefineCall(n)) {
+        substituteUtilGetDefine(n);
+      }
+    }
+
+    private void substituteUtilGetDefine(Node callNode) {
+      Node firstExpr = callNode.getSecondChild();
+      Node secondExpr = callNode.getLastChild();
+
+      if (secondExpr != firstExpr) {
+        secondExpr.detachFromParent();
+      } else {
+        // There is no secondExpr; default to null.
+        secondExpr = IR.nullNode();
+      }
+
+      Node replacement = getDefineReplacement(firstExpr, secondExpr);
+      replacement.useSourceInfoIfMissingFromForTree(callNode);
+      callNode.getParent().replaceChild(callNode, replacement);
+      compiler.reportCodeChange();
+    }
+
+    private Node getDefineReplacement(Node firstExpr, Node secondExpr) {
+      if (defines.contains(firstExpr.getString())) {
+        Node define = NodeUtil.newQName(compiler, firstExpr.getString());
+        Node defineStringValue = NodeUtil.newCallNode(IR.name("String"), define);
+        return IR.comma(secondExpr, defineStringValue);
+      } else {
+        return secondExpr;
+      }
+    }
+
+    private boolean isUtilGetDefineCall(Node n) {
+      return n.isCall() && isUtilGetDefineMethodName(n.getFirstChild().getQualifiedName());
+    }
+
+    private boolean isUtilGetDefineMethodName(String fnName) {
+      return fnName != null && fnName.endsWith("Util.$getDefine");
+    }
+  }
+
   /**
    * Collects references to certain function definitions in a certain class and then inlines fully
    * qualified static method calls to those functions anywhere in the program.
@@ -146,6 +189,17 @@ public J2clPass(AbstractCompiler compiler) {
 
   @Override
   public void process(Node externs, Node root) {
+    /*
+     * Re-writes Util.getDefine to make it work for compiled mode.
+     */
+    Set<String> defines = new ProcessDefines(compiler, null).collectDefines(root).keySet();
+    NodeTraversal.traverseEs6(compiler, root, new GetDefineRewriter(defines));
+
+    /*
+     * Inlines Arrays.$create(), Arrays.$init(), Arrays.$instanceIsOfType(), Arrays.$castTo() and
+     * Casts.to() so that all references to Object.$isInstance() functions will be fully qualified
+     * and easy to strip.
+     */
     inlineFunctionsInFile(
         root,
         "vmbootstrap/Arrays.impl.js",
@@ -156,6 +210,18 @@ public void process(Node externs, Node root) {
         "vmbootstrap/Casts.impl.js",
         ImmutableSet.of("to"),
         InliningMode.DIRECT);
+
+    /*
+     * Inlines all Interface.$markImplementor(FooClass) metaclass calls so that FooClass and others
+     * like it are not unnecessarily retained and so that static analysis of interface instanceof
+     * calls becomes possible.
+     */
+    inlineFunctionsInFile(
+        root, ALL_CLASS_FILE_NAMES, ImmutableSet.of("$markImplementor"), InliningMode.BLOCK);
+
+    /*
+     * Inlines class metadata calls so they become optimizable and avoids escaping of constructor.
+     */
     inlineFunctionsInFile(
         root,
         "nativebootstrap/Util.impl.js",
@@ -165,8 +231,6 @@ public void process(Node externs, Node root) {
             "$setClassMetadataForEnum",
             "$setClassMetadataForPrimitive"),
         InliningMode.BLOCK);
-    inlineFunctionsInFile(
-        root, ALL_CLASS_FILE_NAMES, ImmutableSet.of("$markImplementor"), InliningMode.BLOCK);
   }
 
   private void inlineFunctionsInFile(

diff --git a/src/com/google/javascript/jscomp/ProcessDefines.java b/src/com/google/javascript/jscomp/ProcessDefines.java
@@ -116,10 +116,7 @@ ProcessDefines injectNamespace(GlobalNamespace namespace) {
 
   @Override
   public void process(Node externs, Node root) {
-    if (namespace == null) {
-      namespace = new GlobalNamespace(compiler, root);
-    }
-    overrideDefines(collectDefines(root, namespace));
+    overrideDefines(collectDefines(root));
   }
 
   private void overrideDefines(Map<String, DefineInfo> allDefines) {
@@ -171,8 +168,11 @@ private boolean isValidDefineType(JSTypeExpression expression) {
    * each one.
    * @return A map of {@link DefineInfo} structures, keyed by name.
    */
-  private Map<String, DefineInfo> collectDefines(Node root,
-      GlobalNamespace namespace) {
+  Map<String, DefineInfo> collectDefines(Node root) {
+    if (namespace == null) {
+      namespace = new GlobalNamespace(compiler, root);
+    }
+
     // Find all the global names with a @define annotation
     List<Name> allDefines = new ArrayList<>();
     for (Name name : namespace.getNameIndex().values()) {

diff --git a/test/com/google/javascript/jscomp/J2clPassTest.java b/test/com/google/javascript/jscomp/J2clPassTest.java
@@ -37,6 +37,21 @@ protected CompilerPass getProcessor(final Compiler compiler) {
     return new J2clPass(compiler);
   }
 
+  public void testUtilGetDefine() {
+    String defineAbc = "var a={}; a.b={}; /** @define {boolean} */ a.b.c = true;\n";
+    test(
+        defineAbc + "nativebootstrap.Util.$getDefine('a.b.c', 'def');",
+        defineAbc + "('def', String(a.b.c));");
+    test(
+        defineAbc + "nativebootstrap.Util.$getDefine('a.b.c');",
+        defineAbc + "(null, String(a.b.c));");
+  }
+
+  public void testUtilGetDefine_notDefined() {
+    test("nativebootstrap.Util.$getDefine('not.defined');", "null;");
+    test("nativebootstrap.Util.$getDefine('not.defined', 'def');", "'def';");
+  }
+
   public void testQualifiedInlines() {
     // Arrays functions.
     test(