Fixed Short circuiting of chained commands doesn't work with npm scripts

  • This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.
Nov 17, 2015
Using TCC/LE 14.00.6 x64, commands chained with && in npm scripts do not short circuit, e.g. a nonzero exit code does not stop the next command from running.

For example in a package.json:

scripts: {
pretest: "eslint ./src && npm run build",
test: "mocha ./test"

Running "npm test" from a normal DOS shell, if "eslint ./src" fails, then the next command will not run. Under TCC, however, the exit codes seem to be ignored, and every step runs to completion regardless of outcome.

I tried to reproduce this without using npm scripts - e.g. if I just create a simple node.js app that exists with code zero, and do:

> node app1 && node app2

then it works as expected. So it has something to do with the way npm runs scripts -- in that I believe it launches a new shell instance for the script, and maybe this causes the exit code to get lost? But I can't blame npm since this works fine with a regular cmd shell.

Nov 17, 2015
More information: this actually has do with batch files and not npm scripts. This repository demonstrates the issue.

The wrapper that npm creates for so-called "global" modules (which are really command line applications) looks like this;

@IF EXIST "%~dp0\node.exe" (
"%~dp0\node.exe" "exit1.js" %*
) ELSE (
node "exit1.js" %*

Apparently the exit code returned from within the conditionals (or maybe just any batch file, not sure) is not returned to the consumer.

In the repository above I have two scripts "exit1.cmd" and "exit0.cmd" which do what you'd expect using the construct above. This:

> exit1 && exit0


This process exits with code 1
This process exits with code 0

running under TCC/LE. In a normal dos shell it returns

This process exits with code 1

as expected.