Bug 1251790 - Add help for "interface objects", r=terrence

js/src/shell/OSObject.cpp

@@ -756,14 +756,21 @@ DefineOS(JSContext* cx, HandleObject global, bool fuzzingSafe)
             return false;
     }
 
+    if (!GenerateInterfaceHelp(cx, osfile, "os.file"))
+        return false;
+
     RootedObject ospath(cx, JS_NewPlainObject(cx));
     if (!ospath ||
         !JS_DefineFunctionsWithHelp(cx, ospath, ospath_functions) ||
-        !JS_DefineProperty(cx, obj, "path", ospath, 0))
+        !JS_DefineProperty(cx, obj, "path", ospath, 0) ||
+        !GenerateInterfaceHelp(cx, ospath, "os.path"))
     {
         return false;
     }
 
+    if (!GenerateInterfaceHelp(cx, obj, "os"))
+        return false;
+
     // For backwards compatibility, expose various os.file.* functions as
     // direct methods on the global.
     RootedValue val(cx);

js/src/shell/js.cpp

@@ -5650,32 +5650,40 @@ PrintHelp(JSContext* cx, HandleObject obj)
     return PrintHelpString(cx, usage) && PrintHelpString(cx, help);
 }
 
+static bool
+PrintEnumeratedHelp(JSContext* cx, HandleObject obj, bool brief)
+{
+    AutoIdVector idv(cx);
+    if (!GetPropertyKeys(cx, obj, JSITER_OWNONLY | JSITER_HIDDEN, &idv))
+        return false;
+
+    for (size_t i = 0; i < idv.length(); i++) {
+        RootedValue v(cx);
+        RootedId id(cx, idv[i]);
+        if (!JS_GetPropertyById(cx, obj, id, &v))
+            return false;
+        if (v.isObject()) {
+            RootedObject funcObj(cx, &v.toObject());
+            if (!PrintHelp(cx, funcObj))
+                return false;
+        }
+    }
+
+    return true;
+}
+
 static bool
 Help(JSContext* cx, unsigned argc, Value* vp)
 {
     CallArgs args = CallArgsFromVp(argc, vp);
-    fprintf(gOutFile, "%s\n", JS_GetImplementationVersion());
 
     RootedObject obj(cx);
     if (args.length() == 0) {
-        RootedObject global(cx, JS::CurrentGlobalOrNull(cx));
-        Rooted<IdVector> ida(cx, IdVector(cx));
-        if (!JS_Enumerate(cx, global, &ida))
-            return false;
+        fprintf(gOutFile, "%s\n", JS_GetImplementationVersion());
 
-        for (size_t i = 0; i < ida.length(); i++) {
-            RootedValue v(cx);
-            RootedId id(cx, ida[i]);
-            if (!JS_GetPropertyById(cx, global, id, &v))
-                return false;
-            if (v.isPrimitive()) {
-                JS_ReportError(cx, "primitive arg");
-                return false;
-            }
-            obj = v.toObjectOrNull();
-            if (!PrintHelp(cx, obj))
-                return false;
-        }
+        RootedObject global(cx, JS::CurrentGlobalOrNull(cx));
+        if (!PrintEnumeratedHelp(cx, global, false))
+            return false;
     } else {
         for (unsigned i = 0; i < args.length(); i++) {
             if (args[i].isPrimitive()) {

js/src/shell/jsshell.cpp

@@ -0,0 +1,69 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// jsshell.cpp - Utilities for the JS shell
+
+#include "shell/jsshell.h"
+
+#include "jsapi.h"
+
+namespace js {
+namespace shell {
+
+bool
+GenerateInterfaceHelp(JSContext* cx, HandleObject obj, const char* name)
+{
+    AutoIdVector idv(cx);
+    if (!GetPropertyKeys(cx, obj, JSITER_OWNONLY | JSITER_HIDDEN, &idv))
+        return false;
+
+    StringBuffer buf(cx);
+    if (!buf.append(' '))
+        return false;
+
+    for (size_t i = 0; i < idv.length(); i++) {
+        RootedValue v(cx);
+        RootedId id(cx, idv[i]);
+        if (!JS_GetPropertyById(cx, obj, id, &v))
+            return false;
+        if (!v.isObject())
+            continue;
+        bool hasHelp = false;
+        RootedObject prop(cx, &v.toObject());
+        if (!JS_GetProperty(cx, prop, "usage", &v))
+            return false;
+        if (v.isString())
+            hasHelp = true;
+        if (!JS_GetProperty(cx, prop, "help", &v))
+            return false;
+        if (v.isString())
+            hasHelp = true;
+        if (hasHelp) {
+            if (!buf.append(' ') ||
+                !buf.append(name, strlen(name)) ||
+                !buf.append('.') ||
+                !buf.append(JSID_TO_FLAT_STRING(id)))
+            {
+                return false;
+            }
+        }
+    }
+
+    RootedString s(cx, buf.finishString());
+    if (!s || !JS_DefineProperty(cx, obj, "help", s, 0))
+        return false;
+
+    if (!buf.append(name, strlen(name)) || !buf.append(" - interface object", 20))
+        return false;
+    s = buf.finishString();
+    if (!s || !JS_DefineProperty(cx, obj, "usage", s, 0))
+        return false;
+
+    return true;
+}
+
+} // namespace shell
+} // namespace js

js/src/shell/jsshell.h

@@ -26,6 +26,9 @@ my_GetErrorMessage(void* userRef, const unsigned errorNumber);
 void
 my_ErrorReporter(JSContext* cx, const char* message, JSErrorReport* report);
 
+bool
+GenerateInterfaceHelp(JSContext* cx, HandleObject obj, const char* name);
+
 JSString*
 FileAsString(JSContext* cx, const char* pathname);
 

js/src/shell/moz.build

@@ -13,6 +13,7 @@ if CONFIG['JS_SHELL_NAME']:
 UNIFIED_SOURCES += [
     'js.cpp',
     'jsoptparse.cpp',
+    'jsshell.cpp',
     'OSObject.cpp'
 ]