Moves NodeSubject and `TypeSubject into "rhino/testing" so that the…

…y are available to Rhino tests.

This change also simplifies the implementation of the subject methods by better leveraging Truth's extension API.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=206884548

src/com/google/javascript/rhino/testing/NodeSubject.java

@@ -0,0 +1,106 @@
+/*
+ *
+ * ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (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.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Rhino code, released
+ * May 6, 1999.
+ *
+ * The Initial Developer of the Original Code is
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 1997-1999
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Bob Jervis
+ *   Google Inc.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License Version 2 or later (the "GPL"), in which
+ * case the provisions of the GPL are applicable instead of those above. If
+ * you wish to allow use of your version of this file only under the terms of
+ * the GPL and not to allow others to use your version of this file under the
+ * MPL, indicate your decision by deleting the provisions above and replacing
+ * them with the notice and other provisions required by the GPL. If you do
+ * not delete the provisions above, a recipient may use your version of this
+ * file under either the MPL or the GPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+package com.google.javascript.rhino.testing;
+
+import static com.google.common.truth.Truth.assertAbout;
+
+import com.google.common.truth.FailureMetadata;
+import com.google.common.truth.Subject;
+import com.google.javascript.rhino.Node;
+import com.google.javascript.rhino.Token;
+import javax.annotation.CheckReturnValue;
+
+/**
+ * A Truth Subject for the Node class. Usage:
+ *
+ * <pre>
+ *   import static com.google.javascript.rhino.testing.NodeSubject.assertNode;
+ *   ...
+ *   assertNode(node1).isEqualTo(node2);
+ *   assertNode(node1).hasType(Token.FUNCTION);
+ * </pre>
+ */
+public final class NodeSubject extends Subject<NodeSubject, Node> {
+  @CheckReturnValue
+  public static NodeSubject assertNode(Node node) {
+    return assertAbout(nodes()).that(node);
+  }
+
+  public static Subject.Factory<NodeSubject, Node> nodes() {
+    return NodeSubject::new;
+  }
+
+  private NodeSubject(FailureMetadata failureMetadata, Node node) {
+    super(failureMetadata, node);
+  }
+
+  public void isEqualTo(Node node) {
+    check("checkTreeEquals(%s)", node).that(actual().checkTreeEquals(node)).isNull();
+  }
+
+  public void hasType(Token type) {
+    hasToken(type);
+  }
+
+  public void hasToken(Token token) {
+    check("getToken()").that(actual().getToken()).isEqualTo(token);
+  }
+
+  public void isName(String name) {
+    check("isName()").that(actual().isName()).isTrue();
+    check("getString()").that(actual().getString()).isEqualTo(name);
+  }
+
+  public void matchesQualifiedName(String qname) {
+    check("matchesQualifiedName(%s)", qname).that(actual().matchesQualifiedName(qname)).isTrue();
+  }
+
+  public void hasCharno(int charno) {
+    check("getCharno()").that(actual().getCharno()).isEqualTo(charno);
+  }
+
+  public void hasLineno(int lineno) {
+    check("getLineno()").that(actual().getLineno()).isEqualTo(lineno);
+  }
+
+  public void hasLength(int length) {
+    check("getLength()").that(actual().getLength()).isEqualTo(length);
+  }
+}