Introduce matchesName as an alternative to matchesQualifiedName. Curr…

…ently, matchesQualifiedName is overused and we would like to start moving away from "QualifiedName" as a key concept. Additionally, matchesName this is more efficient than matchesQualifiedName for the case of matching NAME nodes. A follow up CL will replace the obvious places matchesQualifiedName can be replaced with matchesName.

While we are here add a few missing test cases for "super"

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=258170284

src/com/google/javascript/rhino/Node.java

@@ -2148,6 +2148,35 @@ public final boolean isQualifiedName() {
     }
   }
 
+  /**
+   * Returns whether a node matches a simple name, such as
+   * <code>x</code>, returns false if this is not a NAME node.
+   */
+  public final boolean matchesName(String name) {
+    if (token != token.NAME) {
+      return false;
+    }
+    String internalString = getString();
+    return !internalString.isEmpty() && name.equals(internalString);
+  }
+
+  /**
+   * Check that if two NAME node match, returns false if either node is
+   * not a NAME node. As a empty string is not considered a
+   * valid Name (it is an AST placeholder), empty strings are never
+   * considered to be matches.
+   */
+  @SuppressWarnings("ReferenceEquality")
+  public final boolean matchesName(Node n) {
+    if (token != token.NAME || n.token != Token.NAME) {
+      return false;
+    }
+
+    // ==, rather than equal as it is intern'd in setString
+    String internalString = getString();
+    return internalString != "" && internalString == n.getString();
+  }
+
   /**
    * Returns whether a node matches a simple or a qualified name, such as
    * <code>x</code> or <code>a.b.c</code> or <code>this.a</code>.
@@ -2197,7 +2226,8 @@ public final boolean matchesQualifiedName(Node n) {
     switch (token) {
       case NAME:
         // ==, rather than equal as it is intern'd in setString
-        return !getString().isEmpty() && getString() == n.getString();
+        String internalString = getString();
+        return internalString != "" && internalString == n.getString();
       case THIS:
       case SUPER:
         return true;
@@ -2218,10 +2248,12 @@ public final boolean matchesQualifiedName(Node n) {
    * a "this" reference, such as <code>a.b.c</code>, but not <code>this.a</code>
    * .
    */
+  @SuppressWarnings("ReferenceEquality")
   public final boolean isUnscopedQualifiedName() {
     switch (this.getToken()) {
       case NAME:
-        return !getString().isEmpty();
+        // Both string are intern'd.
+        return getString() != "";
       case GETPROP:
         return getFirstChild().isUnscopedQualifiedName();
       default:

test/com/google/javascript/rhino/NodeTest.java

@@ -251,8 +251,19 @@ public void testMatchesQualifiedName1() {
     assertThat(qname("this.b").matchesQualifiedName("a.b")).isFalse();
     assertThat(qname("this.b").matchesQualifiedName(".b")).isFalse();
     assertThat(qname("this.b").matchesQualifiedName("a.")).isFalse();
+    assertThat(qname("this.b").matchesQualifiedName("super.b")).isFalse();
     assertThat(qname("this.b").matchesQualifiedName("this.b")).isTrue();
 
+    assertThat(qname("super").matchesQualifiedName("super")).isTrue();
+    assertThat(qname("super").matchesQualifiedName("superx")).isFalse();
+
+    assertThat(qname("super.b").matchesQualifiedName("a")).isFalse();
+    assertThat(qname("super.b").matchesQualifiedName("a.b")).isFalse();
+    assertThat(qname("super.b").matchesQualifiedName(".b")).isFalse();
+    assertThat(qname("super.b").matchesQualifiedName("a.")).isFalse();
+    assertThat(qname("super.b").matchesQualifiedName("this.b")).isFalse();
+    assertThat(qname("super.b").matchesQualifiedName("super.b")).isTrue();
+
     assertThat(qname("a.b.c").matchesQualifiedName("a.b.c")).isTrue();
     assertThat(qname("a.b.c").matchesQualifiedName("a.b.c")).isTrue();
 
@@ -293,8 +304,14 @@ public void testMatchesQualifiedName2() {
 
     assertThat(qname("this.b").matchesQualifiedName(qname("a"))).isFalse();
     assertThat(qname("this.b").matchesQualifiedName(qname("a.b"))).isFalse();
+    assertThat(qname("this.b").matchesQualifiedName(qname("super.b"))).isFalse();
     assertThat(qname("this.b").matchesQualifiedName(qname("this.b"))).isTrue();
 
+    assertThat(qname("super.b").matchesQualifiedName(qname("a"))).isFalse();
+    assertThat(qname("super.b").matchesQualifiedName(qname("a.b"))).isFalse();
+    assertThat(qname("super.b").matchesQualifiedName(qname("this.b"))).isFalse();
+    assertThat(qname("super.b").matchesQualifiedName(qname("super.b"))).isTrue();
+
     assertThat(qname("a.b.c").matchesQualifiedName(qname("a.b.c"))).isTrue();
     assertThat(qname("a.b.c").matchesQualifiedName(qname("a.b.c"))).isTrue();
 
@@ -324,6 +341,28 @@ public void testMatchesQualifiedName2() {
     assertThat(new Node(Token.INC, IR.name("x")).matchesQualifiedName(qname("x"))).isFalse();
   }
 
+  @Test
+  public void testMatchesName() {
+    // Empty string are treat as unique.
+    assertThat(IR.name("").matchesName("")).isFalse();
+
+    assertThat(IR.name("a").matchesName("a")).isTrue();
+    assertThat(IR.name("a").matchesName("a.b")).isFalse();
+    assertThat(IR.name("a").matchesName("")).isFalse();
+
+    assertThat(IR.thisNode().matchesName("this")).isFalse();
+    assertThat(IR.superNode().matchesName("super")).isFalse();
+  }
+
+  @Test
+  public void testMatchesNameNodes() {
+    assertThat(IR.name("a").matchesName(qname("a"))).isTrue();
+    assertThat(IR.name("a").matchesName(qname("a.b"))).isFalse();
+
+    assertThat(IR.thisNode().matchesName(qname("this"))).isFalse();
+    assertThat(IR.superNode().matchesName(qname("super"))).isFalse();
+  }
+
   public static Node qname(String name) {
     int endPos = name.indexOf('.');
     if (endPos == -1) {
@@ -333,6 +372,8 @@ public static Node qname(String name) {
     String nodeName = name.substring(0, endPos);
     if ("this".equals(nodeName)) {
       node = IR.thisNode();
+    } else if ("super".equals(nodeName)) {
+      node = IR.superNode();
     } else {
       node = IR.name(nodeName);
     }
@@ -504,8 +545,11 @@ public void testInvalidSourceOffset() {
   public void testQualifiedName() {
     assertThat(IR.name("").getQualifiedName()).isNull();
     assertThat(IR.name("a").getQualifiedName()).isEqualTo("a");
+    assertThat(IR.thisNode().getQualifiedName()).isEqualTo("this");
+    assertThat(IR.superNode().getQualifiedName()).isEqualTo("super");
     assertThat(IR.getprop(IR.name("a"), IR.string("b")).getQualifiedName()).isEqualTo("a.b");
     assertThat(IR.getprop(IR.thisNode(), IR.string("b")).getQualifiedName()).isEqualTo("this.b");
+    assertThat(IR.getprop(IR.superNode(), IR.string("b")).getQualifiedName()).isEqualTo("super.b");
     assertThat(IR.getprop(IR.call(IR.name("a")), IR.string("b")).getQualifiedName()).isNull();
   }