clone IPC objects and remove unserializable values

packages/desktop-gui/src/lib/ipc-bus.js

@@ -62,6 +62,18 @@ const ipcBus = (...args) => {
   // get the last argument
   const lastArg = args.pop()
 
+  // remove nodes that cannot be cloned
+  // https://github.com/cypress-io/cypress/issues/6750
+  args = args.map((arg) => {
+    return _.cloneDeepWith(arg, (val) => {
+      if (_.isFunction(val) || _.isElement(val)) {
+        return null
+      }
+
+      return val
+    })
+  })
+
   let fn
 
   // enable the last arg to be a function

packages/server/lib/gui/events.coffee

@@ -21,12 +21,21 @@ chromePolicyCheck = require("../util/chrome_policy_check")
 browsers    = require("../browsers")
 konfig      = require("../konfig")
 
+removeUnserializableValues = (obj) =>
+  ## remove values that cannot be cloned
+  ## https://github.com/cypress-io/cypress/issues/6750
+  _.cloneDeepWith obj, (val) =>
+    if _.isFunction(val)
+      return null
+
 handleEvent = (options, bus, event, id, type, arg) ->
   debug("got request for event: %s, %o", type, arg)
 
-  sendResponse = (data = {}) ->
+  sendResponse = (originalData = {}) ->
     try
-      debug("sending ipc data %o", {type: type, data: data})
+      data = removeUnserializableValues(originalData)
+
+      debug("sending ipc data %o", { type, data, originalData })
       event.sender.send("response", data)
 
   sendErr = (err) ->
@@ -318,7 +327,9 @@ handleEvent = (options, bus, event, id, type, arg) ->
       throw new Error("No ipc event registered for: '#{type}'")
 
 module.exports = {
-  handleEvent: handleEvent
+  removeUnserializableValues
+
+  handleEvent
 
   stop: ->
     ipc.removeAllListeners()

packages/server/test/unit/gui/events_spec.coffee

@@ -158,7 +158,7 @@ describe "lib/gui/events", ->
       it "calls Windows#open with args and resolves with return of Windows.open", ->
         @handleEvent("window:open", {type: "INDEX"})
         .then (assert) =>
-          assert.sendCalledWith(@win)
+          assert.sendCalledWith(events.removeUnserializableValues(@win))
 
       it "catches errors", ->
         err = new Error("foo")