From 8f358a20881b61cf3256fa1e404b86d5f104932d Mon Sep 17 00:00:00 2001
From: Alex Dvornikov <advornikov@fb.com>
Date: Thu, 11 Jan 2018 14:11:00 -0800
Subject: [PATCH] Report module id as string and as double, in case of invalid
 values are passed to nativeRequire

Differential Revision: D6695769

fbshipit-source-id: b578b9d52ed711fb5a3e51717ac555fa8a232d7a
---
 ReactCommon/cxxreact/JSCUtils.cpp | 24 +++++++++---------------
 ReactCommon/jschelpers/Value.cpp  |  9 +++++++++
 ReactCommon/jschelpers/Value.h    |  9 +++++++++
 3 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/ReactCommon/cxxreact/JSCUtils.cpp b/ReactCommon/cxxreact/JSCUtils.cpp
index 96ede8f6ae7a06..74942bc629b3d6 100644
--- a/ReactCommon/cxxreact/JSCUtils.cpp
+++ b/ReactCommon/cxxreact/JSCUtils.cpp
@@ -2,6 +2,8 @@
 
 #include "JSCUtils.h"
 
+#include <folly/Conv.h>
+
 namespace facebook {
 namespace react {
 
@@ -17,28 +19,20 @@ std::pair<uint32_t, uint32_t> parseNativeRequireParameters(
     const JSGlobalContextRef& context,
     const JSValueRef arguments[],
     size_t argumentCount) {
-  double moduleId = 0, bundleId = 0;
+  uint32_t moduleId = 0, bundleId = 0;
 
+  // use "getNumber" & "folly::to" to throw explicitely in case of an overflow
+  // error during conversion
   if (argumentCount == 1) {
-    moduleId = Value(context, arguments[0]).asNumber();
+    moduleId = folly::to<uint32_t>(Value(context, arguments[0]).getNumberOrThrow());
   } else if (argumentCount == 2) {
-    moduleId = Value(context, arguments[0]).asNumber();
-    bundleId = Value(context, arguments[1]).asNumber();
+    moduleId = folly::to<uint32_t>(Value(context, arguments[0]).getNumberOrThrow());
+    bundleId = folly::to<uint32_t>(Value(context, arguments[1]).getNumberOrThrow());
   } else {
     throw std::invalid_argument("Got wrong number of args");
   }
 
-  if (moduleId < 0) {
-    throw std::invalid_argument(folly::to<std::string>("Received invalid module ID: ",
-                                                       Value(context, arguments[0]).toString().str()));
-  }
-
-  if (bundleId < 0) {
-    throw std::invalid_argument(folly::to<std::string>("Received invalid bundle ID: ",
-                                                       Value(context, arguments[1]).toString().str()));
-  }
-
-  return std::make_pair(static_cast<uint32_t>(bundleId), static_cast<uint32_t>(moduleId));
+  return std::make_pair(bundleId, moduleId);
 }
 
 }
diff --git a/ReactCommon/jschelpers/Value.cpp b/ReactCommon/jschelpers/Value.cpp
index f084335f3032c1..72e303b18a152d 100644
--- a/ReactCommon/jschelpers/Value.cpp
+++ b/ReactCommon/jschelpers/Value.cpp
@@ -191,6 +191,15 @@ Value Value::makeError(JSContextRef ctx, const char *error, const char *stack)
   }
 }
 
+void Value::throwTypeException(const std::string &expectedType) const {
+  std::string wat("TypeError: Expected ");
+  wat += expectedType;
+  wat += ", instead got '";
+  wat += toString().str();
+  wat += "'";
+  throw JSException(wat.c_str());
+}
+
 Object::operator Value() const {
   return Value(m_context, m_obj);
 }
diff --git a/ReactCommon/jschelpers/Value.h b/ReactCommon/jschelpers/Value.h
index d78103a8418482..e7df097096fd40 100644
--- a/ReactCommon/jschelpers/Value.h
+++ b/ReactCommon/jschelpers/Value.h
@@ -302,6 +302,13 @@ class Value : public noncopyable {
     }
   }
 
+  double getNumberOrThrow() const {
+    if (!isNumber()) {
+      throwTypeException("Number");
+    }
+    return JSC_JSValueToNumber(context(), m_value, nullptr);
+  }
+
   int32_t asInteger() const {
     return static_cast<int32_t>(asNumber());
   }
@@ -355,7 +362,9 @@ class Value : public noncopyable {
   JSContextRef m_context;
   JSValueRef m_value;
 
+  void throwTypeException(const std::string &expectedType) const;
   static JSValueRef fromDynamicInner(JSContextRef ctx, const folly::dynamic& obj);
+
 };
 
 } }