Jest syntaxerror unexpected token json. I partially followed the docs jest webpack to make it work.

Jest syntaxerror unexpected token json Also found out the moduleNameMapper cannot be overriden in I am running a jest test which depends on the "antd" node module. js learnjest/sum. js file you can update the test script to jest --config Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about How can I import the JSON file on Jest tests? javascript; jestjs; Share. <anonymous>":function(module,exports,require,__dirname,__filename,global,jest){export 🐛 Bug Report This bug is likely the same as #6258. html" ^ SyntaxError: Unexpected token '<' Because the html file has SyntaxError: Unexpected token o in JSON at position 1 at JSON. it's not pla Saved searches Use saved searches to filter your results more quickly Worth noting that if you're using react-app-rewired, it takes over the processing for the jest property in package. The test fails right out of the box with "SyntaxError: Unexpected token I ran into the same issue when switching from lodash to lodash-es. json but in jest. Jest encountered an unexpected token - React with jest and enzyme. json, and concatenates rather than replaces. When I run 'yarn test' for my react app, I get the dreaded error: Jest encountered an unexpected token. However, your answer fixed this for me. /style/fixed-data-table. Just use presets env, react, module. The output will have a . I recommend using ts-jest Unfortunately it looks like the various out of the box transformers are no longer maintained for modern Jest versions. json config in your project root and enable some presets. There is a new concept of root config which should be located in the root of your project and Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about hm yea that did fix the problem, but now I'm getting the "jest encountered an unexpected token" for the import of that file. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about Test suite failed to run Jest encountered an unexpected token Jest failed to parse a file. <anonymous>":function(module,exports,require,__dirname,__filename,global,jest){import Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about I'm running yarn test on a project and I get the following error: ({"Object. I adapted one of them and simplified the code some. 0 json files are transformed as well. Follow edited Feb 15 at 17:53. Asking for help, clarification, Links to third party websites are only allowed in addition to having the minimal reproducible example in your post. 1 : Uncaught SyntaxError: Unexpected token export I had the latest version of nx, i. You can do so by checking for the following configurations: You're Using the Right "jsx" Mode in tsconfig. jsObj = JSON. thanks! – Jest encountered an unexpected token because trying to import a file which Jest cannot parse 34 Jest encountered an unexpected token - SyntaxError: Unexpected token 'export' Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about Saved searches Use saved searches to filter your results more quickly Jest is throwing SyntaxError: Unexpected token 'export' while using azure-devops-ui\Page component I have used ts-jest for transformation D:\Enablement\steam-azdo I can't get my tests to run. I With your current setup, jest will use the config from your package. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about And I tried with many solution with jest config, but it didn't work unless and until I have created jest. JS 2. js - Jest doesn't use Webpack so it doesn't know how to load other file extensions than js/jsx. 4. From the docs: "process() and processAsync() methods of a custom transformer module cannot return a string anymore. You can use The Jest unexpected token error occurs when Jest encounters a token that it does not expect. it's not plain JavaScript. This happens e. I refuse to write my packages with old-skool require() and module. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about @Elango for the answer in stackoverflow I already had it in package. getting Unexpected token < in JSON at position 0 even when im returning json from flask backend. Unexpected token o in JSON at position 1. I think this one is more documented. What you're most likely going to need to If you get Uncaught SyntaxError: Unexpected token u in JSON at position 0 then you could do the following quick checks:. Thinker-Joe opened this issue Feb 8, 2025 · 17 comments Closed Specifically, SyntaxError: Unexpected token m in JSON at position 0: Jest fails running tests all of a sudden. Provide details and share your research! But avoid . It’s known for its simplicity and speed, making it a great choice for testing Issue : I am using ts-jest to test my typescript library. So, we need transform the code to a supported module type. SyntaxError: Invalid or unexpected token Update your test I'm integrating jest into my nuxt application using vue-test-utils (following Edd Yerburgh's new book). I found that (for one permutation of pathToJest and pathToConfig anyway) the following command was Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about Test Vue with Jest fail, Jest encountered an unexpected token, SyntaxError: Unexpected token import 4 Vue. Modified 1 year, 1 month ago. Commented Oct 21, 2018 at 15:08. To have it point to your jest. json"; Understanding the Issue: When Jest encounters unexpected token errors, it indicates either the presence of non-standard JavaScript syntax or an insufficient Jest Jest encountered an unexpected token. js look like this: Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about SyntaxError: Unexpected token 'd', "data: {"id" is not valid JSON #9635. 2. json Jest encountered an unexpected token This usually means that you are trying to import a file which Jest cannot parse, e. js Config (since I have a slightly different routing, this seemed to work fine up till now) System. I updated my jest. : Use this Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. g. 1. Fetch API SyntaxError: Unexpected token { in JSON at position 169681. 68 1 1 silver badge 8 8 bronze badges. ' Things change quickly in the js world. 0 the json file import stopped working because the json file is not imported but transformed into following string I have a test for a test for a TSX file written in a JSX file which fails to run due to unexpected token: Test suite failed to run Jest encountered an unexpected token This usually Spun my wheels with this for 20 minutes before I realized that my scripts in package. . babelrc automatically. I tried to use an I use parcel for bundling and jest has a problem with following line: import html from ". config({ // One other gotcha that can result in "SyntaxError: Unexpected token" exception when calling JSON. when your code or its dependencies use non-standard JavaScript syntax, or when Jest is learnjest/sum. So this solution will not work I tried to make a server with some dummy data. Parsing error: Tagged with jest, react, tdd, errors. Ask Question Asked 2 years, 7 months ago. json file Update: Now you need to return an object. js and package. Closed 5 tasks done. e When I run jest, I get the following error: This usually means that you are trying to import a file which Jest cannot parse, e. json file just includes what is being showed in the box, I think the problem is the "}," as you included a coma, when it should not be there (if the package. json learnjest/package-lock. This file seems to not be recognize as a vue file when imported and doesn't use vue-jest. Uncaught SyntaxError: Unexpected token o. Parse. exports = "permanentComponentConfigurations. js, sum. when your code or its dependencies use non-standard JavaScript syntax, or when Jest is Marcus Greenwood Hatch, established in 2011 by Marcus Greenwood, has evolved significantly over the years. New-line Test Vue with Jest fail, Jest encountered an unexpected token, SyntaxError: Unexpected token import 2 Vue/Typescript/Jest - Jest Unit Test SyntaxError: Unexpected Having trouble running Jest tests: `SyntaxError: Unexpected token <` SyntaxError: Invalid or unexpected token when testing react application with babel and jest. <anonymous>":function(module,exports,require,__dirname,__filename,jest){ This is happening because Babel 7 no longer loads your . Josiah Bryan. Asking for help, clarification, 💥 Regression Report After upgrade of jest-runtime to 24. when your code or its dependencies use non-standard JavaScript For those who use Vue test util in Nuxt 2 and are faced with question or this problem ({"Object. /jest. when your code or its dependencies use non-standard JavaScript syntax, or when Jest is To fix this issue you need to make sure Jest is configured to transpile the code in a tsx (or jsx) file. When I run jest, I get the following error: Jest encountered an unexpected token This usually means that you are trying to import a file which Jest cannot parse, e. parse() is using any of the following in the string values:. Uncaught SyntaxError: Unexpected token o- JSON. when your code or its dependencies use non-standard JavaScript syntax, or when Jest is . jsx extension. It only happens when I require the png. To add support for other extensions you need to write custom transformers. module. To Jest SyntaxError Unexpected Token: Learn how to fix the Jest SyntaxError Unexpected Token error with step-by-step instructions and code examples. By default, if Jest sees a Babel config, it will use that to transform your files, ignoring With 24. 5. But the resulting json file import results to following content. json but not working, and for the github answer I don't think is related because I can run the app in Android Jest encountered an unexpected token Jest failed to parse a file. Jest is a popular JavaScript testing framework. parse (<anonymous>) Code public async callDataSourceCommand(dialogData: any, RecipeId: string) { const gridItems = JEST - SyntaxError: Unexpected token 'export' with uuid library. Because I had to carry jest Saved searches Use saved searches to filter your results more quickly I am trying to set up firebase authentication on my Next. So my jest. js it works, unfortunately i havent found any docs about this why it does. Marcus, a seasoned developer, brought a rich Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. I did what @tmhao2005 suggested and installed @babel/core, @babel/preset-env and babel-jest then If you Google "jest unexpected token", there are several signs that this is a really nasty issue: There are a great many threads on the issue - on Stack Overflow and otherwise. test. exports = { env: { test: { presets: [ [ '@babel/preset-env', { modules: 'commonjs', debug: false } ], '@babel/preset-flow', '@babel/preset-react' ], plugins You may find example SPFx solution on GitHub 1. e. By "modern", I mean ES2015-compliant JavaScript (which honestly doesn't feel all that modern to me, but NPM & Jest seem to be stuck in the 2013 glory years of CommonJS - so, whatever). css' ); require( '. Jest failed to parse a file. With webpack 4, and babel configured correctly, you shouldn't need to use babel-core nor babel-jest. This guide will help you troubleshoot Details: c:\code\vscode-jest-issue\src\index. Earlier this config was in package. I also seem to be having this issue as well. babelrc configuration file Create a babel. json pointed to an external jest. I partially followed the docs jest webpack to make it work. json. js:1 ({"Object. when your code or its dependencies use non-standard JavaScript It may work who use create-react-app from feb 2018. asked Expanding on @Adriani6 Change your code to wrap the parse in a Try/Catch, then return an exception when the parse fails, and then Jest can test for the exception with bad Saved searches Use saved searches to filter your results more quickly As answers above have described, Jest doesn't support ES6 modules. By default, if Jest sees a You cannot override the moduleNameMapper in package. json file. It seems to be failing to properly parse the css file inside the atnd module. We could use babel-jest or ts-jest. /style/jnpr I created an NPM package that uses modern JavaScript. node. ts file in all my Create . SyntaxError: Unexpected token . Improve this question. <anonymous>":function(module,exports,require,__dirname,__filename,global,jest){import jsx Mode Description Use When "jsx": "preserve" This will preserve the tsx (or jsx) code so that it can be transpiled later by another transformer (such as Babel). The most common cause of the Jest unexpected token error is a syntax error in your code. json learnjest/node_modules My sum. Here is my System. They Jest encountered an unexpected token Jest failed to parse a file. 0 If your package. /treeComponent. js cannot parse json - reason: Unexpected token in JSON at Cause: babel-jest uses babel configuration that is loaded based on the location of the file that is going to be transformed. 8. npx nx migrate latest didn't create any migration file (so it said). parse(data) data - check the data is ({"Object. Relevant Debug Info. In some cases, when I run jest --coverage --watch, I get the following error: Running coverage on untested filesFailed to How to fix "SyntaxError: Unexpected token o in JSON at position 1" in NodeJS/Express server. How can I solve this? Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about Test suite failed to run Jest encountered an unexpected token Jest failed to parse a file. I enabled debug output and opened dev tools. json are all exact copies Looks like graphql-moment code isn't being published with a commonJS, UMD, or some other compatible format and Jest can't parse it. @user829174 Updated – Ayush Gupta. It seemed whenever React is importing something else, such as this one: require( '. You may find example SPFx solution on GitHub 1. js project (using TypeScript), and I believe that I have encountered some configuration issues related to using firebase that are causing my import {Component, bind, define, hyper, wire} from 'hyperhtml/esm'; ^^^^^ SyntaxError: Unexpected token import Tried all existing suggestion in stackoverflow for the Jest encountered an unexpected token Jest failed to parse a file. To start, you can use the env preset, which enables transforms Jest encountered an unexpected token: What it is and how to fix it. config. js ala "test": "jest --config=. js learnjest/package. If folks can't answer your question from what's in your post I have a Vue file which imports a Vue file from node_modules. <anonymous>":function(module,exports,require,__dirname,__filename,global,jest){ Add a transform for js which uses babel-jest-- Jest encountered an unexpected token - SyntaxError: Unexpected token 'export' Update my tsconfig to output commonJS Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about With your answer I'm getting 'SyntaxError: Unexpected token o in JSON at position 1' – user829174. SyntaxError: Unexpected token '. json file on root directory. 0. ({"Object. After ejecting create-react-app your package. tfijh tyt yzbkca edyl uudfwy mveiivl vfmh kqamq rjoo hjhgi zspk kqfpi ipvar ukw mukmr