From bd370f6f604a4fdb8fcd1588edc52fec5193e359 Mon Sep 17 00:00:00 2001
From: Jordan Harband <ljharb@gmail.com>
Date: Tue, 26 Mar 2019 10:34:49 -0400
Subject: [PATCH] [Fix] `mount`/`shallow`: `renderProp`: improve error messages

---
 .../test/shared/methods/renderProp.jsx        | 27 ++++++++++++++++++-
 packages/enzyme/src/ReactWrapper.js           |  6 ++---
 packages/enzyme/src/ShallowWrapper.js         |  6 ++---
 3 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/packages/enzyme-test-suite/test/shared/methods/renderProp.jsx b/packages/enzyme-test-suite/test/shared/methods/renderProp.jsx
index 99db157a6..4b6a3eb84 100644
--- a/packages/enzyme-test-suite/test/shared/methods/renderProp.jsx
+++ b/packages/enzyme-test-suite/test/shared/methods/renderProp.jsx
@@ -13,6 +13,7 @@ import { is } from '../../_helpers/version';
 export default function describeRenderProp({
   Wrap,
   WrapRendered,
+  WrapperName,
 }) {
   wrap()
     .withConsoleThrows()
@@ -25,7 +26,7 @@ export default function describeRenderProp({
       class Bar extends React.Component {
         render() {
           const { render: r } = this.props;
-          return <div className="in-bar">{r()}</div>;
+          return <div className="in-bar">{typeof r === 'function' && r()}</div>;
         }
       }
       class RendersBar extends React.Component {
@@ -50,6 +51,30 @@ export default function describeRenderProp({
         expect(stub.args).to.deep.equal([['one', 'two']]);
       });
 
+      it('throws on a non-string prop name', () => {
+        const wrapper = Wrap(<RendersBar render={() => {}} />);
+        expect(() => wrapper.renderProp()).to.throw(
+          TypeError,
+          `${WrapperName}::renderProp(): \`propName\` must be a string`,
+        );
+      });
+
+      it('throws on a missing prop', () => {
+        const wrapper = Wrap(<RendersBar render={() => {}} />);
+        expect(() => wrapper.renderProp('nope')).to.throw(
+          Error,
+          `${WrapperName}::renderProp(): no prop called “nope“ found`,
+        );
+      });
+
+      it('throws on a non-function render prop value', () => {
+        const wrapper = Wrap(<RendersBar render={{}} />);
+        expect(() => wrapper.renderProp('render')).to.throw(
+          TypeError,
+          `${WrapperName}::renderProp(): expected prop “render“ to contain a function, but it holds “object“`,
+        );
+      });
+
       it('throws on host elements', () => {
         class Div extends React.Component {
           render() {
diff --git a/packages/enzyme/src/ReactWrapper.js b/packages/enzyme/src/ReactWrapper.js
index 87c048713..64ed81e16 100644
--- a/packages/enzyme/src/ReactWrapper.js
+++ b/packages/enzyme/src/ReactWrapper.js
@@ -794,15 +794,15 @@ class ReactWrapper {
         throw new TypeError('ReactWrapper::renderProp() can only be called on custom components');
       }
       if (typeof propName !== 'string') {
-        throw new TypeError('`propName` must be a string');
+        throw new TypeError('ReactWrapper::renderProp(): `propName` must be a string');
       }
       const props = this.props();
       if (!has(props, propName)) {
-        throw new Error(`no prop called “${propName}“ found`);
+        throw new Error(`ReactWrapper::renderProp(): no prop called “${propName}“ found`);
       }
       const propValue = props[propName];
       if (typeof propValue !== 'function') {
-        throw new TypeError(`expected prop “${propName}“ to contain a function, but it holds “${typeof prop}“`);
+        throw new TypeError(`ReactWrapper::renderProp(): expected prop “${propName}“ to contain a function, but it holds “${typeof propValue}“`);
       }
 
       return (...args) => {
diff --git a/packages/enzyme/src/ShallowWrapper.js b/packages/enzyme/src/ShallowWrapper.js
index b72b414db..7c2e79f6d 100644
--- a/packages/enzyme/src/ShallowWrapper.js
+++ b/packages/enzyme/src/ShallowWrapper.js
@@ -1191,15 +1191,15 @@ class ShallowWrapper {
         throw new TypeError('ShallowWrapper::renderProp() can only be called on custom components');
       }
       if (typeof propName !== 'string') {
-        throw new TypeError('`propName` must be a string');
+        throw new TypeError('ShallowWrapper::renderProp(): `propName` must be a string');
       }
       const props = this.props();
       if (!has(props, propName)) {
-        throw new Error(`no prop called “${propName}“ found`);
+        throw new Error(`ShallowWrapper::renderProp(): no prop called “${propName}“ found`);
       }
       const propValue = props[propName];
       if (typeof propValue !== 'function') {
-        throw new TypeError(`expected prop “${propName}“ to contain a function, but it holds “${typeof prop}“`);
+        throw new TypeError(`ShallowWrapper::renderProp(): expected prop “${propName}“ to contain a function, but it holds “${typeof propValue}“`);
       }
 
       return (...args) => {