fix: handle objects created by Object.create(null) that can throw an error

`TypeError: Cannot convert object to primitive value` in Chromium
`TypeError: can't convert Object to string` in Firefox

Author: piquark6046

userscript/source/index.ts

@@ -24,6 +24,7 @@ export function RunTinyShieldUserscript(BrowserWindow: typeof window, Userscript
   const OriginalArrayMap = BrowserWindow.Array.prototype.map
   const OriginalString = BrowserWindow.String
   const OriginalArrayJoin = BrowserWindow.Array.prototype.join
+  const OriginalObjectGetPrototypeOf = BrowserWindow.Object.getPrototypeOf
 
   const ProtectedFunctionStrings = ['toString', 'get', 'set']
 
@@ -49,7 +50,7 @@ export function RunTinyShieldUserscript(BrowserWindow: typeof window, Userscript
         return Reflect.apply(Target, ThisArg, Args)
       }
 
-      let ArgText = SafeArrayToString(Args, { OriginalArrayMap, OriginalString, OriginalArrayJoin })
+      let ArgText = SafeArrayToString(Args, { OriginalArrayMap, OriginalString, OriginalArrayJoin, OriginalObjectGetPrototypeOf })
       if (ASInitPositiveRegExps.filter(ASInitPositiveRegExp => ASInitPositiveRegExp.filter(Index => OriginalRegExpTest.call(Index, ArgText) as boolean).length >= 2).length === 1) {
         console.debug(`[${UserscriptName}]: Map.prototype.get:`, ThisArg, Args)
         throw new Error()
@@ -71,7 +72,7 @@ export function RunTinyShieldUserscript(BrowserWindow: typeof window, Userscript
   BrowserWindow.Map.prototype.set = new Proxy(BrowserWindow.Map.prototype.set, {
     apply(Target: (key: unknown, value: unknown) => Map<unknown, unknown>, ThisArg: Map<unknown, unknown>, Args: [unknown, unknown]) {
       let ArgText = ''
-      ArgText = SafeArrayToString(Args, { OriginalArrayMap, OriginalString, OriginalArrayJoin })
+      ArgText = SafeArrayToString(Args, { OriginalArrayMap, OriginalString, OriginalArrayJoin, OriginalObjectGetPrototypeOf })
       if (ASReinsertedAdvInvenPositiveRegExps.filter(ASReinsertedAdvInvenPositiveRegExp => ASReinsertedAdvInvenPositiveRegExp.filter(Index => OriginalRegExpTest.call(Index, ArgText) as boolean).length >= 3).length === 1) {
         console.debug(`[${UserscriptName}]: Map.prototype.set:`, ThisArg, Args)
         throw new Error()

userscript/source/safe-ArrayToString.ts

@@ -2,12 +2,20 @@ type OriginalAPI = {
   OriginalArrayMap: typeof Array.prototype.map
   OriginalString: typeof String
   OriginalArrayJoin: typeof Array.prototype.join
+  OriginalObjectGetPrototypeOf: typeof Object.getPrototypeOf
 }
 
 export function SafeArrayToString(This: unknown[], OriginalAPI: OriginalAPI): string {
+
   const Mapped = OriginalAPI.OriginalArrayMap.call(
     This,
-    (Value: unknown) => OriginalAPI.OriginalString(Value)
+    (Value: unknown) => {
+      if (Value && typeof Value === 'object' && OriginalAPI.OriginalObjectGetPrototypeOf(Value) === null) {
+        return '[Object: null prototype]'
+      }
+
+      return OriginalAPI.OriginalString(Value)
+    }
   ) as string[]
 
   return OriginalAPI.OriginalArrayJoin.call(Mapped) as string