8201817: Taglet.init should be called with the "primary" doclet

Reviewed-by: ksrini

src/jdk.javadoc/share/classes/jdk/javadoc/doclet/StandardDoclet.java

@@ -44,7 +44,7 @@ public class StandardDoclet implements Doclet {
     private final HtmlDoclet htmlDoclet;
 
     public StandardDoclet() {
-        htmlDoclet = new HtmlDoclet();
+        htmlDoclet = new HtmlDoclet(this);
     }
 
     @Override

src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/formats/html/HtmlDoclet.java

@@ -31,6 +31,7 @@ import javax.lang.model.element.ModuleElement;
 import javax.lang.model.element.PackageElement;
 import javax.lang.model.element.TypeElement;
 
+import jdk.javadoc.doclet.Doclet;
 import jdk.javadoc.doclet.DocletEnvironment;
 import jdk.javadoc.doclet.Reporter;
 import jdk.javadoc.internal.doclets.toolkit.AbstractDoclet;
@@ -59,8 +60,8 @@ import jdk.javadoc.internal.doclets.toolkit.util.IndexBuilder;
  */
 public class HtmlDoclet extends AbstractDoclet {
 
-    public HtmlDoclet() {
+    public HtmlDoclet(Doclet parent) {
-        configuration = new HtmlConfiguration(this);
+        configuration = new HtmlConfiguration(parent);
     }
 
     @Override // defined by Doclet

src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/toolkit/BaseConfiguration.java

@@ -42,6 +42,9 @@ import com.sun.tools.javac.util.DefinedBy.Api;
 import jdk.javadoc.doclet.Doclet;
 import jdk.javadoc.doclet.DocletEnvironment;
 import jdk.javadoc.doclet.Reporter;
+import jdk.javadoc.doclet.StandardDoclet;
+import jdk.javadoc.doclet.Taglet;
+import jdk.javadoc.internal.doclets.formats.html.HtmlDoclet;
 import jdk.javadoc.internal.doclets.toolkit.builders.BuilderFactory;
 import jdk.javadoc.internal.doclets.toolkit.taglets.TagletManager;
 import jdk.javadoc.internal.doclets.toolkit.util.DocFile;
@@ -356,7 +359,15 @@ public abstract class BaseConfiguration {
     /**
      * Constructs the configurations needed by the doclet.
      *
-     * @param doclet the doclet that created this configuration
+     * @apiNote
+     * The {@code doclet} parameter is used when {@link Taglet#init(DocletEnvironment, Doclet)
+     * initializing tags}.
+     * Some doclets (such as the {@link StandardDoclet), may delegate to another
+     * (such as the {@link HtmlDoclet}).  In such cases, the primary doclet (i.e
+     * {@code StandardDoclet}) should be provided here, and not any internal
+     * class like {@code HtmlDoclet}.
+     *
+     * @param doclet the doclet for this run of javadoc
      */
     public BaseConfiguration(Doclet doclet) {
         this.doclet = doclet;

test/langtools/jdk/javadoc/doclet/testUserTaglet/TestUserTaglet.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2017, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -23,7 +23,7 @@
 
 /*
  * @test
- * @bug      8176836
+ * @bug      8176836 8201817
  * @summary  Provide Taglet with context
  * @library  ../lib
  * @modules jdk.javadoc/jdk.javadoc.internal.tool
@@ -52,7 +52,7 @@ public class TestUserTaglet extends JavadocTester {
         checkOutput("pkg/C.html", true,
             "<li>Element: CLASS C",
             "<li>Element supertypes: [java.lang.Object]",
-            "<li>Doclet: class jdk.javadoc.internal.doclets.formats.html.HtmlDoclet"
+            "<li>Doclet: class jdk.javadoc.doclet.StandardDoclet"
         );
     }
 }