javascript - Cypress.io 上的存根函数被忽略

Question

我的组件如下

import {myMethod} from "./myFile"

function MyComponent(){
   const output = myMethod();
   console.log({output})    

   return <div></div>    
}

我正在存根 myMethod 因为我希望它像这样返回一个特定的值

import * as Parent from "./myFile"
cy.stub(Parent, "myMethod", () => "i was stubbed")

cy.visit("/my_component")  # Does not use the stubbed function 

但是后来我发现该组件仍然使用原始函数而不是存根函数，有人知道我在做什么错吗？

标签： javascriptreactjscypressend-to-endstubbing

Answer 1

你必须设置 babelplugin-transform-modules-commonjs插件loose: true

[
    '@babel/plugin-transform-modules-commonjs',
    {
        loose: true,
    },
]

您的示例配置cypress/plugins/index.js

const { startDevServer } = require('@cypress/webpack-dev-server');
const findReactScriptsWebpackConfig = require('@cypress/react/plugins/react-scripts/findReactScriptsWebpackConfig');

// taken from https://github.com/cypress-io/code-coverage/issues/461#issuecomment-859292331
function customDevServer(
    on,
    config,
    { webpackConfigPath } = {
        webpackConfigPath: 'react-scripts/config/webpack.config',
    }
) {
    on('dev-server:start', async (options) => {
        const webpackConfig = findReactScriptsWebpackConfig(config, {
            webpackConfigPath,
        });
        const rules = webpackConfig.module.rules.find((rule) => !!rule.oneOf).oneOf;
        const babelRule = rules.find((rule) => /babel-loader/.test(rule.loader));
        babelRule.options.plugins.push(require.resolve('babel-plugin-istanbul'), [
            '@babel/plugin-transform-modules-commonjs',
            {
                loose: true,
            },
        ]);
        return startDevServer({
            options,
            webpackConfig,
        });
    });

    config.env.reactDevtools = true;

    return config;
}

module.exports = (on, config) => {
    if (config.testingType === 'component') {
        customDevServer(on, config);
    }

    require('@cypress/code-coverage/task')(on, config);

    return config;
};

github上的问题链接：https ://github.com/cypress-io/cypress/issues/18662