Skip emitting provided inner classes redundantly in processUnprovidedTypes()

src/main/java/com/google/javascript/clutz/DeclarationGenerator.java

@@ -724,8 +724,7 @@ private void processUnprovidedTypes(Set<String> provides, Set<String> transitive
         }
 
         // skip provided symbols (as default or in an namespace).
-        if (provides.contains(name)
-            || (!transitiveProvides.contains(name) && provides.contains(namespace))) {
+        if (isProvidedSymbol(provides, transitiveProvides, name)) {
           continue;
         }
 
@@ -764,6 +763,35 @@ private void processUnprovidedTypes(Set<String> provides, Set<String> transitive
     }
   }
 
+  /** Returns true if the symbol is already provided as default or in a namespace. */
+  private boolean isProvidedSymbol(
+      Set<String> provides, Set<String> transitiveProvides, String name) {
+    if (provides.contains(name)) {
+      return true;
+    }
+    if (transitiveProvides.contains(name)) {
+      return false;
+    }
+    String namespace = getNamespace(name);
+    Boolean innerClass = false;
+    while (!namespace.isEmpty()) {
+      final TypedVar symbol = this.compiler.getTopScope().getOwnSlot(namespace);
+      if (symbol == null) {
+        return false;
+      }
+      // inner class-like of default export is emitted recursively
+      if (provides.contains(namespace) && (!innerClass || isDefaultExport(symbol))) {
+        return true;
+      }
+      if (!isClassLike(symbol.getType())) {
+        return false;
+      }
+      namespace = getNamespace(namespace);
+      innerClass = true;
+    }
+    return false;
+  }
+
   /**
    * If any inputs declare a legacy namespace, emit aliases for their exports in goog.module style.
    */

src/test/java/com/google/javascript/clutz/double_inner_class_with_referenced_props.d.ts

@@ -0,0 +1,22 @@
+declare namespace ಠ_ಠ.clutz {
+  class module$exports$ns$DoubleInnerClassWithRef {
+    private noStructuralTyping_module$exports$ns$DoubleInnerClassWithRef : any;
+  }
+}
+declare namespace ಠ_ಠ.clutz.module$exports$ns$DoubleInnerClassWithRef {
+  interface Inner {
+    baz (e1 : ಠ_ಠ.clutz.module$exports$ns$DoubleInnerClassWithRef.Inner.Enum1 , e2 : ಠ_ಠ.clutz.module$exports$ns$DoubleInnerClassWithRef.Inner.Enum2 ) : void ;
+  }
+}
+declare namespace ಠ_ಠ.clutz.module$exports$ns$DoubleInnerClassWithRef.Inner {
+  enum Enum1 {
+    FOO = 'foo' ,
+  }
+  enum Enum2 {
+    BAR = 'bar' ,
+  }
+}
+declare module 'goog:ns.DoubleInnerClassWithRef' {
+  import DoubleInnerClassWithRef = ಠ_ಠ.clutz.module$exports$ns$DoubleInnerClassWithRef;
+  export default DoubleInnerClassWithRef;
+}

src/test/java/com/google/javascript/clutz/double_inner_class_with_referenced_props.js

@@ -0,0 +1,30 @@
+goog.module('ns.DoubleInnerClassWithRef');
+
+class A {}
+
+/**
+ * @interface
+ */
+A.Inner = function() {};
+
+/**
+ * @enum {string}
+ */
+A.Inner.Enum1 = {
+  FOO: 'foo'
+};
+
+/**
+ * @enum {string}
+ */
+A.Inner.Enum2 = {
+  BAR: 'bar'
+};
+
+/**
+ * @param {A.Inner.Enum1} e1
+ * @param {A.Inner.Enum2} e2
+ */
+A.Inner.prototype.baz = function(e1, e2) {};
+
+exports = A;

src/test/java/com/google/javascript/clutz/inner_class_of_private_class.d.ts

@@ -0,0 +1,22 @@
+declare namespace ಠ_ಠ.clutz.ns.inner_class_of_private_class {
+  class FooType_ {
+    private noStructuralTyping_ns_inner_class_of_private_class_FooType_ : any;
+    foo (inner : ಠ_ಠ.clutz.ns.inner_class_of_private_class.FooType_.Inner ) : void ;
+  }
+}
+declare module 'goog:ns.inner_class_of_private_class' {
+  import inner_class_of_private_class = ಠ_ಠ.clutz.ns.inner_class_of_private_class;
+  export = inner_class_of_private_class;
+}
+declare namespace ಠ_ಠ.clutz.ns.inner_class_of_private_class {
+  let FooInstance : ಠ_ಠ.clutz.ns.inner_class_of_private_class.FooType_ ;
+}
+declare module 'goog:ns.inner_class_of_private_class.FooInstance' {
+  import FooInstance = ಠ_ಠ.clutz.ns.inner_class_of_private_class.FooInstance;
+  export default FooInstance;
+}
+declare namespace ಠ_ಠ.clutz.ns.inner_class_of_private_class.FooType_ {
+  class Inner {
+    private noStructuralTyping_ns_inner_class_of_private_class_FooType__Inner : any;
+  }
+}

src/test/java/com/google/javascript/clutz/inner_class_of_private_class.js

@@ -0,0 +1,26 @@
+goog.provide('ns.inner_class_of_private_class');
+goog.provide('ns.inner_class_of_private_class.FooInstance');
+
+//!! This is a generalized code of `goog.debug.Trace`.
+//!! https://github.com/google/closure-library/blob/master/closure/goog/debug/tracer.js
+
+/**
+ * @constructor
+ * @private
+ */
+ns.inner_class_of_private_class.FooType_ = function() {};
+
+/**
+ * @param {!ns.inner_class_of_private_class.FooType_.Inner} inner
+ */
+ns.inner_class_of_private_class.FooType_.prototype.foo = function(inner) {};
+
+/**
+ * @constructor
+ */
+ns.inner_class_of_private_class.FooType_.Inner = function() {};
+
+/**
+ * @type {!ns.inner_class_of_private_class.FooType_}
+ */
+ns.inner_class_of_private_class.FooInstance = new ns.inner_class_of_private_class.FooType_();