feature: improve error message when no transferrables are transferred (…

…#95)

src/parts/FixNodeParameters/FixNodeParameters.ts

@@ -1,4 +1,5 @@
 import * as GetTransferrables from '../GetTransferrables/GetTransferrables.ts'
+import { IpcError } from '../IpcError/IpcError.ts'
 import * as RemoveValues from '../RemoveValues/RemoveValues.ts'
 
 // workaround for node not supporting transferrable objects
@@ -7,7 +8,7 @@ import * as RemoveValues from '../RemoveValues/RemoveValues.ts'
 export const fixNodeParameters = (value: unknown) => {
   const transfer = GetTransferrables.getTransferrables(value)
   if (transfer.length === 0) {
-    throw new Error('no transferrables found')
+    throw new IpcError('no transferrables found')
   }
   const newValue = RemoveValues.removeValues(value, transfer)
   return {

test/FixNodeParameters.test.ts

@@ -0,0 +1,27 @@
+import { expect, test } from '@jest/globals'
+import * as FixNodeParameters from '../src/parts/FixNodeParameters/FixNodeParameters.ts'
+
+test('error - no transferrables found', () => {
+  const value = {
+    jsonrpc: '2.0',
+    method: 'CreateMessagePort.createMessagePort',
+    params: [],
+  }
+  expect(() => FixNodeParameters.fixNodeParameters(value)).toThrow(new Error('no transferrables found'))
+})
+
+test('transfer messagePort', () => {
+  const { port1 } = new MessageChannel()
+  const value = {
+    jsonrpc: '2.0',
+    method: 'CreateMessagePort.createMessagePort',
+    params: [, port1],
+  }
+  const { newValue, transfer } = FixNodeParameters.fixNodeParameters(value)
+  expect(newValue).toEqual({
+    jsonrpc: '2.0',
+    method: 'CreateMessagePort.createMessagePort',
+    params: [],
+  })
+  expect(transfer).toBe(port1)
+})