Throw error with stack trace when launching with an invalid executablePath option

[austinkelleher]

When puppeteer is used as a dependency or sub-dependency of another project that exposes the puppeteer API, an invalid executablePath option should be reported appropriately. Currently, if an invalid executablePath is provided to puppeteer.launch(...), it is unclear where the actual error is coming from. It could be from any module. This error should be propagated with a stack trace directly from puppeteer. I have a fix for this and I will put up a PR momentarily.

Steps to reproduce

Tell us about your environment:

• Puppeteer version: 0.11.0-alpha
• Platform / OS version: macOS 10.12.6

What steps will reproduce the problem?

Please include code that reproduces the issue.

1. await puppeteer.launch({ executablePath: 'random-path' })

What is the expected result?

An error containing a stack trace clearly describing the issue e.g.

Error: Error launching Chromium process with executable path "random-path"
    at fs.stat (/puppeteer/lib/Launcher.js:147:23)
    at FSReqWrap.oncomplete (fs.js:152:21)

What happens instead?

events.js:182
      throw er; // Unhandled 'error' event
      ^

Error: spawn random-path ENOENT
    at exports._errnoException (util.js:1016:11)
    at Process.ChildProcess._handle.onexit (internal/child_process.js:189:19)
    at onErrorNT (internal/child_process.js:366:16)
    at _combinedTickCallback (internal/process/next_tick.js:102:11)
    at process._tickCallback (internal/process/next_tick.js:161:9)

[austinkelleher]

Fixed in: #751