replace IThenable (closure extern) with PromiseLike (lib.d.ts)

Author: rkirov

src/main/java/com/google/javascript/cl2dts/DeclarationGenerator.java

@@ -633,19 +633,24 @@ public Void caseTemplatizedType(TemplatizedType type) {
             emit("[]");
             return null;
           }
-          // Arguments<?> and NodeList<?> in es3 externs are correspondinly
-          // IArguments and NodeList interfaces (not-parametrized) in lib.d.ts.
-          // New* are temporary work-arounds for upstream externs.
-          // TODO(rado): upgrade closure compiler and remove them.
-          if (type.getDisplayName().equals("Arguments") ||
-              type.getDisplayName().equals("NewArguments")) {
-            emit("IArguments");
-            return null;
-          }
-          if (type.getDisplayName().equals("NodeList") ||
-              type.getDisplayName().equals("NewNodeList")) {
-            emit("NodeList");
-            return null;
+          switch(type.getDisplayName()) {
+            // Arguments<?> and NodeList<?> in es3 externs are correspondinly
+            // IArguments and NodeList interfaces (not-parametrized) in lib.d.ts.
+            // New* are temporary work-arounds for upstream externs.
+            // TODO(rado): upgrade closure compiler and remove them.
+            case "Arguments":
+            case "NewArguments":{
+              emit("IArguments");
+              return null;
+            }
+            case "NodeList":
+            case "NewNodeList": {
+              emit("NodeList");
+              return null;
+            }
+            case "IThenable": {
+              templateTypeName = "PromiseLike";
+            }
           }
           Iterator<JSType> it = type.getTemplateTypes().iterator();
           if (typeRegistry.getNativeType(OBJECT_TYPE).equals(referencedType)) {

src/test/java/com/google/javascript/cl2dts/types_with_externs.d.ts

@@ -16,6 +16,8 @@ declare namespace ಠ_ಠ.cl2dts_internal.typesWithExterns {
   var c : NodeList | IArguments | { length : number } ;
   function id (x : NodeList | IArguments | { length : number } ) : NodeList | IArguments | { length : number } ;
   function topLevelFunction ( ...a : any [] ) : any ;
+  interface ExtendsIThenable extends PromiseLike < any > {
+  }
 }
 declare module 'goog:typesWithExterns' {
   import alias = ಠ_ಠ.cl2dts_internal.typesWithExterns;

src/test/java/com/google/javascript/cl2dts/types_with_externs.js

@@ -92,4 +92,10 @@ typesWithExterns.id = function(x) { return x; }
 /**
  * @type {!Function}
  */
-typesWithExterns.topLevelFunction = function() {};
+typesWithExterns.topLevelFunction = function() {};
+
+/**
+ * @interface
+ * @extends {IThenable}
+ */
+typesWithExterns.ExtendsIThenable = function() {};