clean-stack

Clean up error stack traces

Removes the mostly unhelpful internal Node.js entries.

Also works in the browser and Electron.

Install

npm install clean-stack

Usage

import cleanStack from 'clean-stack';

const error = new Error('Missing unicorn');

console.log(error.stack);
/*
Error: Missing unicorn
    at Object.<anonymous> (/Users/sindresorhus/dev/clean-stack/unicorn.js:2:15)
    at Module._compile (module.js:409:26)
    at Object.Module._extensions..js (module.js:416:10)
    at Module.load (module.js:343:32)
    at Function.Module._load (module.js:300:12)
    at Function.Module.runMain (module.js:441:10)
    at startup (node.js:139:18)
*/

console.log(cleanStack(error.stack));
/*
Error: Missing unicorn
    at Object.<anonymous> (/Users/sindresorhus/dev/clean-stack/unicorn.js:2:15)
*/

API

cleanStack(stack, options?)

Returns the cleaned stack or undefined if the given stack is not a string.

stack

Type: string | undefined

The stack property of an Error, or undefined.

options

Type: object

pretty

Type: boolean
Default: false

Prettify the file paths in the stack:

• /Users/sindresorhus/dev/clean-stack/unicorn.js:2:15 → ~/dev/clean-stack/unicorn.js:2:15
• file:///Users/sindresorhus/dev/clean-stack/unicorn.js:2:15 → ~/dev/clean-stack/unicorn.js:2:15

When enabled, file URLs are converted to regular paths for better readability and IDE integration. URLs that cannot be converted, contain ? or #, or decode to a line break are left unchanged.

pretty and basePath only rewrite frame paths. Backslashes become / throughout each frame. Error message text is preserved except for blank lines; lines shaped like frames are treated as frames.

basePath

Type: string?

Remove the given base path from stack trace file paths, effectively turning absolute paths into relative ones. It will also transform absolute file URLs into relative paths.

Supports absolute or relative paths, either separator, and the filesystem root. A leading slash only matches absolute paths. Relative base paths do not match inside file:///, except Windows drive paths such as C:/Users.

Example with '/Users/sindresorhus/dev/clean-stack' as basePath:

/Users/sindresorhus/dev/clean-stack/unicorn.js:2:15 → unicorn.js:2:15

[!NOTE] basePath matches before file URLs are decoded, so /Users/John Doe/dev does not match file:///Users/John%20Doe/dev. After a match, remaining URL escapes stay encoded, even with pretty.

[!NOTE] Frames like at fn (unicorn.js:2:15) are removed because they resemble old internal Node.js frames. Cleaning again after basePath produces this form can therefore drop frames for files directly in the base path. Paths with a directory, like at fn (src/unicorn.js:2:15), and bare frames like at unicorn.js:2:15 are unaffected.

pathFilter

Type: (path: string) => boolean

Remove stack lines where the callback returns false. It receives the path without the closing parenthesis, with / separators, before basePath or pretty is applied. A pathless frame such as at async Promise.all (index 0) yields index 0.

[!NOTE] Balanced parentheses in function names, such as at render (partial) (/base/a.js:6:9), and paths, such as C:/Program Files (x86)/app.js:1:1, are supported. Unbalanced parentheses in a function name, such as at a(b (/base/a.js:6:9), can cause part of the name to be included in the path.

import cleanStack from 'clean-stack';

const error = new Error('Missing unicorn');

console.log(cleanStack(error.stack));
// Error: Missing unicorn
//     at Object.<anonymous> (/Users/sindresorhus/dev/clean-stack/unicorn.js:2:15)
//     at Object.<anonymous> (/Users/sindresorhus/dev/clean-stack/omit-me.js:1:16)

const pathFilter = path => !/omit-me/.test(path);

console.log(cleanStack(error.stack, {pathFilter}));
// Error: Missing unicorn
//     at Object.<anonymous> (/Users/sindresorhus/dev/clean-stack/unicorn.js:2:15)

Related

• extract-stack - Extract the actual stack of an error
• stack-utils - Captures and cleans stack traces