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Unexpected end of JSON input

See original GitHub issue

First of all I love this utility, thanks for making!

I am getting the following error:

SyntaxError: Unexpected end of JSON input
    at JSON.parse (<anonymous>)
    at getDependencyTree (/Users/me/.config/yarn/global/node_modules/cost-of-modules/lib/helpers.js:64:17)
    at Object.getRootDependencies (/Users/me/.config/yarn/global/node_modules/cost-of-modules/lib/helpers.js:73:26)
    at Object.<anonymous> (/Users/me/.config/yarn/global/node_modules/cost-of-modules/lib/index.js:26:32)
    at Module._compile (module.js:569:30)
    at Object.Module._extensions..js (module.js:580:10)
    at Module.load (module.js:503:32)
    at tryModuleLoad (module.js:466:12)
    at Function.Module._load (module.js:458:3)
    at Function.Module.runMain (module.js:605:10)

My package.json is:

{
  "name": "gtest",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "devDependencies": {
    "gulp": "gulpjs/gulp#4.0",
    "gulp-cli": "^1.3.0"
  }
}

I am using npm 5.0.0, and I suspect that the issue relates to npm ls --json printing errors after printing the json (note that sync-exec channels both STDOUT and STDERR and returns the combination).

You should probably use:

const {spawnSync} = require('child_process')
const proc = spawnSync('npm', ['ls', '--json'])
console.log(JSON.parse(proc.stdout.toString()))
// ignore proc.stderr

Erroneous “JSON” output (note STDERR at end):

{
  "name": "gtest",
  "version": "1.0.0",
  "problems": [
    "invalid: gulp@4.0.0-alpha.2 /Users/me/Desktop/gtest/node_modules/gulp",
    "extraneous: glob-watcher@3.2.0 /Users/me/Desktop/gtest/node_modules/glob-watcher",
    "extraneous: undertaker@1.1.0 /Users/me/Desktop/gtest/node_modules/undertaker",
    "extraneous: vinyl-fs@2.4.4 /Users/me/Desktop/gtest/node_modules/vinyl-fs",
    "extraneous: node-pre-gyp@0.6.36 /Users/me/Desktop/gtest/node_modules/node-pre-gyp"
  ],
  "dependencies": {
    "...": "..."
  }
}
npm ERR! invalid: gulp@4.0.0-alpha.2 /Users/me/Desktop/gtest/node_modules/gulp
npm ERR! extraneous: glob-watcher@3.2.0 /Users/me/Desktop/gtest/node_modules/glob-watcher
npm ERR! extraneous: undertaker@1.1.0 /Users/me/Desktop/gtest/node_modules/undertaker
npm ERR! extraneous: vinyl-fs@2.4.4 /Users/me/Desktop/gtest/node_modules/vinyl-fs
npm ERR! extraneous: node-pre-gyp@0.6.36 /Users/me/Desktop/gtest/node_modules/node-pre-gyp

Issue Analytics

State:
Created 6 years ago
Reactions:6
Comments:6 (1 by maintainers)

Top GitHub Comments

2reactions

tvvigneshcommented, Mar 29, 2020

Same issue on my end. Works well in one project, but throws unexpected end of json in another. Screenshot below.

Screenshot from 2020-03-29 23-48-34

0reactions

michaelfarrell76commented, Feb 7, 2021

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