Fix bug caused by things with undefined prototypes

A user was doing td.replace('aws-sdk'), which is massive and contains a
lot of really screwy prototype manipulation that apparently has at least
one type with an undefined in the prototype chain of one of its
functions.

This guards against that. The test isn't perfect because I wasn't even
able to reproduce the same prototype chain nonsense

Author: searls

src/imitate/overwrite-children/gather-props.js

@@ -1,10 +1,12 @@
 import _ from '../../wrap/lodash'
 
+import isPrimitiveLike from './is-primitive-like'
+
 export default (thing) => {
   const originalThing = thing
   const props = {}
 
-  while (!isNativePrototype(thing)) {
+  while (!isPrimitiveLike(thing) && !isNativePrototype(thing)) {
     Object.getOwnPropertyNames(thing).forEach((propName) => {
       if (!props[propName] && propName !== 'constructor') {
         props[propName] = Object.getOwnPropertyDescriptor(thing, propName)

test/unit/imitate/overwrite-children/gather-props.test.js

@@ -106,6 +106,13 @@ module.exports = {
 
     assert.deepEqual(_.keys(result), ['foo', 'bar'])
   },
+  'is primitive-y': () => {
+    assert.deepEqual(subject(null), {})
+    assert.deepEqual(subject(undefined), {})
+    assert.deepEqual(subject(false), {})
+    assert.deepEqual(subject(true), {})
+    assert.deepEqual(subject(5), {})
+  },
   'extending a native type': () => {
     const Thing = function () {}
     Thing.prototype = Object.create(Map.prototype)

test/unit/imitate/overwrite-children/index.test.js

@@ -9,13 +9,11 @@ module.exports = {
 
     td.when(isPrimitiveLike(td.matchers.anything())).thenReturn(false)
   },
-  'thing is primitive-like (then do nothing)': () => {
-    const target = {}
-    td.when(isPrimitiveLike(target)).thenReturn(true)
+  'target is primitive-like (then do nothing)': () => {
+    td.when(isPrimitiveLike('some target')).thenReturn(true)
 
-    subject('some original', target, () => { throw new Error('do not fire!') })
+    subject('some original', 'some target', () => { throw new Error('do not fire!') })
 
-    assert.deepEqual(target, {})
     td.verify(gatherProps(), {ignoreExtraArgs: true, times: 0})
     td.verify(copyProps(), {ignoreExtraArgs: true, times: 0})
     td.verify(chainPrototype(), {ignoreExtraArgs: true, times: 0})