# Testing plugins with mocha
**URL:** https://discourse.joplinapp.org/t/testing-plugins-with-mocha/27166
**Category:** Development
**Created:** [2 September 2022 09:59 UTC](https://discourse.joplinapp.org/t/testing-plugins-with-mocha/27166 "2022-09-02T09:59:50Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@banan314](https://discourse.joplinapp.org/u/banan314)
#### Post date: [2 September 2022 09:59 UTC](https://discourse.joplinapp.org/t/testing-plugins-with-mocha/27166/1 "2022-09-02T09:59:50Z")
Has anybody tested the plugin using mocha or jest? I tried to run it, but I get errors all the time.
My code is
**index.ts**
```auto
export function decreaseHeaderLevel(selection: string): string {
return selection.replace(/^(#+)\s./, '#');
}
```
**index.spec.ts**
```auto
import { decreaseHeaderLevel } from 'src/index';
var assert = require('assert');
describe('Decrease level header', function () {
describe('function', function () {
it('should replace ## with #', function () {
assert.equal(decreaseHeaderLevel('### rient'), '## rient');
});
});
});
```
**package.json**
```json
"test": "ts-mocha -p tsconfig.json src/**/*.spec.ts"
```
**tsconfig.json**
```json
{
"typeRoots": [
"types"
],
"compilerOptions": {
"outDir": "./dist/",
"module": "commonjs",
"target": "es2015",
"jsx": "react",
"allowJs": true,
"baseUrl": ".",
"paths": {
"@/*": [
"src/*"
]
}
},
"include": [
"src/**/*.ts",
"tests/**/*.ts"
],
"exclude": [
"node_modules",
".vscode"
]
}
```
And I get errors:
1. Running `mocha`
```auto
TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension ".ts" for /home/kamil/Documents/IT/projects/joplin-formatter-plugin/src/index.spec.ts
```
1. Running `ts-mocha`
```auto
> joplin-plugin-my-formatter@1.0.0 test
> ts-mocha -p tsconfig.json src/**/*.spec.ts
Error: Cannot find module 'src/index'
Require stack:
...
at Object. (/home/kamil/Documents/IT/projects/joplin-formatter-plugin/src/index.spec.ts:1:1)
```
---
### Author:  [@JackGruber](https://discourse.joplinapp.org/u/JackGruber)
#### Post date: [2 September 2022 10:46 UTC](https://discourse.joplinapp.org/t/testing-plugins-with-mocha/27166/2 "2022-09-02T10:46:24Z")
Yes with jest in my projects [joplin-plugin-backup](https://github.com/JackGruber/joplin-plugin-backup) and [joplin-plugin-note-overview](https://github.com/JackGruber/joplin-plugin-note-overview)