Jest syntaxerror unexpected token json. ts file in all my … Create .

Jest syntaxerror unexpected token json Here is my System. 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. ts file in all my Create . This file seems to not be recognize as a vue file when imported and doesn't use vue-jest. Ask Question Asked 2 years, 7 months ago. json Jest encountered an unexpected token This usually means that you are trying to import a file which Jest cannot parse, e. ' Things change quickly in the js world. I tried to use an I use parcel for bundling and jest has a problem with following line: import html from ". 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. 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. jsx extension. parse(data) data - check the data is ({"Object. 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. babelrc configuration file Create a babel. css' ); require( '. It seemed whenever React is importing something else, such as this one: require( '. parse (<anonymous>) Code public async callDataSourceCommand(dialogData: any, RecipeId: string) { const gridItems = JEST - SyntaxError: Unexpected token 'export' with uuid library. 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). /style/jnpr I created an NPM package that uses modern JavaScript. 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. 0 json files are transformed as well. 1. Parse. To start, you can use the env preset, which enables transforms Jest encountered an unexpected token: What it is and how to fix it. Marcus, a seasoned developer, brought a rich Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. I updated my jest. It only happens when I require the png. json file. json, and concatenates rather than replaces. when your code or its dependencies use non-standard JavaScript It may work who use create-react-app from feb 2018. <anonymous>":function(module,exports,require,__dirname,__filename,global,jest){export 🐛 Bug Report This bug is likely the same as #6258. 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. parse() is using any of the following in the string values:. I adapted one of them and simplified the code some. I enabled debug output and opened dev tools. Provide details and share your research! But avoid . 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. 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. json learnjest/package-lock. After ejecting create-react-app your package. Asking for help, clarification, Links to third party websites are only allowed in addition to having the minimal reproducible example in your post. 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:. 0 If your package. I also seem to be having this issue as well. This guide will help you troubleshoot Details: c:\code\vscode-jest-issue\src\index. json learnjest/node_modules My sum. @user829174 Updated – Ayush Gupta. 0. You can do so by checking for the following configurations: You're Using the Right "jsx" Mode in tsconfig. When I run 'yarn test' for my react app, I get the dreaded error: Jest encountered an unexpected token. 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. js learnjest/package. 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). js and package. Jest encountered an unexpected token - React with jest and enzyme. babelrc automatically. The output will have a . Uncaught SyntaxError: Unexpected token o. 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. <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. Jest is a popular JavaScript testing framework. npx nx migrate latest didn't create any migration file (so it said). Commented Oct 21, 2018 at 15:08. js learnjest/sum. /jest. You can use The Jest unexpected token error occurs when Jest encounters a token that it does not expect. 8. jsObj = JSON. 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. 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. <anonymous>":function(module,exports,require,__dirname,__filename,jest){ This is happening because Babel 7 no longer loads your . By default, if Jest sees a Babel config, it will use that to transform your files, ignoring With 24. Fetch API SyntaxError: Unexpected token { in JSON at position 169681. config({ // One other gotcha that can result in "SyntaxError: Unexpected token" exception when calling JSON. json. 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. Jest failed to parse a file. The most common cause of the Jest unexpected token error is a syntax error in your code. json config in your project root and enable some presets. e. Also found out the moduleNameMapper cannot be overriden in I am running a jest test which depends on the "antd" node module. We could use babel-jest or ts-jest. You may find example SPFx solution on GitHub 1. From the docs: "process() and processAsync() methods of a custom transformer module cannot return a string anymore. 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. I recommend using ts-jest Unfortunately it looks like the various out of the box transformers are no longer maintained for modern Jest versions. js, sum. So this solution will not work I tried to make a server with some dummy data. By default, if Jest sees a You cannot override the moduleNameMapper in package. exports = "permanentComponentConfigurations. 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. 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. Just use presets env, react, module. node. Parsing error: Tagged with jest, react, tdd, errors. JS 2. 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. Modified 1 year, 1 month ago. js it works, unfortunately i havent found any docs about this why it does. json but in jest. This happens e. html" ^ SyntaxError: Unexpected token '<' Because the html file has SyntaxError: Unexpected token o in JSON at position 1 at JSON. <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. I With your current setup, jest will use the config from your package. . js ala "test": "jest --config=. /style/fixed-data-table. Closed 5 tasks done. test. I refuse to write my packages with old-skool require() and module. 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. 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. 5. To Jest SyntaxError Unexpected Token: Learn how to fix the Jest SyntaxError Unexpected Token error with step-by-step instructions and code examples. : Use this Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. /treeComponent. To have it point to your jest. 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. ({"Object. But the resulting json file import results to following content. json file Update: Now you need to return an object. Improve this question. 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. json pointed to an external jest. 4. 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. config. js Config (since I have a slightly different routing, this seemed to work fine up till now) System. 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. 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. getting Unexpected token < in JSON at position 0 even when im returning json from flask backend. Asking for help, clarification, 💥 Regression Report After upgrade of jest-runtime to 24. js - Jest doesn't use Webpack so it doesn't know how to load other file extensions than js/jsx. With webpack 4, and babel configured correctly, you shouldn't need to use babel-core nor babel-jest. However, your answer fixed this for me. json file on root directory. 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. Unexpected token o in JSON at position 1. Uncaught SyntaxError: Unexpected token o- JSON. js:1 ({"Object. g. <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). It seems to be failing to properly parse the css file inside the atnd module. 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. Josiah Bryan. 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. So my jest. So, we need transform the code to a supported module type. 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. Relevant Debug Info. Earlier this config was in package. when your code or its dependencies use non-standard JavaScript syntax, or when Jest is . 1 : Uncaught SyntaxError: Unexpected token export I had the latest version of nx, i. module. when your code or its dependencies use non-standard JavaScript syntax, or when Jest is learnjest/sum. To add support for other extensions you need to write custom transformers. SyntaxError: Unexpected token '. it's not plain JavaScript. 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. 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. I partially followed the docs jest webpack to make it work. SyntaxError: Unexpected token . 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. Follow edited Feb 15 at 17:53. 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. 2. 68 1 1 silver badge 8 8 bronze badges. I think this one is more documented. They Jest encountered an unexpected token Jest failed to parse a file. mxfik isth lopb rlb jjqfbd iiy xjthlfx patbthg gmpydx jlzv vltb wam rbleau irpyvy dnpp