ng doc does not open the documentation in the browser

[s-a-n-i-n]

🐞 Bug report

Command (mark with an x)

• doc

Is this a regression?

Yes, the previous version in which this bug was not present was: 11.1.2

Description

A clear and concise description of the problem...

Typing ng doc something does not do anything. It does not generate an error and does not open the browser.

🔬 Minimal Reproduction

🔥 Exception or Error

🌍 Your Environment

Angular CLI: 13.0.3
Node: 14.18.0
Package Manager: npm 8.1.4
OS: win32 x64

Angular: 13.0.2
... animations, common, compiler, compiler-cli, core, forms
... platform-browser, platform-browser-dynamic, router

Package                         Version
---------------------------------------------------------
@angular-devkit/architect       0.1300.3
@angular-devkit/build-angular   13.0.3
@angular-devkit/core            13.0.3
@angular-devkit/schematics      13.0.3 (cli-only)
@schematics/angular             13.0.3 (cli-only)
rxjs                            7.4.0
typescript                      4.4.4

Anything else relevant?

Windows 10 machine

Exact same as :
#13575

[alan-agius4]

I am unable to replicate this on OSX.

@dgp1130, can you please try yourself?

[alan-agius4]

Maybe even @gkalpak can take a look at this.

[gkalpak]

I looked into this and here is what is happening on Windows:

• CLI calls and awaits for open() (cli/commands/doc-impl.ts#L52-L54).
• open spawns a new process to run a PowerShell command to open a URL (open/index.js#L199).
• open unrefs and returns the spawned process (open/index.js#L216-L218).
• This resolves the promise returned by DocCommand's run() method.
• This in turn (eventually) leads CLI to call process.exit() (cli/lib/init.ts#L115).
• Apparently, this causes the spawned process to also exit, before the PowerShell command is executed (and the browser opened). FWIW, I also tried with detached: true (and stdio: 'ignore') and it didn't work either 🤷‍♂️

The only things that seemed to work on Windows are the following:

• Either call open() with wait: true (in cli/commands/doc-impl.ts#L53). This still allows the main process to exit, but only after the browser is opened.
• Or switch from process.exit(exitCode) to process.exitCode = exitCode (in cli/lib/init.ts#L115), which (I believe) is generally considered a better practice anyway.

Both options seem reasonable to me, but I am not sure if/how they affect other platforms or other CLI commands.

BTW, if you want an easy way to reproduce this on Windows for debugging, running ng doc asyncpipe is essentially doing the equivalent of:

node --eval "require('open')('https://angular.io/api?query=asyncpipe', {wait: false}).then(() => process.exit(0))"

Or if you want to get rid of open, you can use the following node script (and run it with node test.js):

// test.js
const proc = require('child_process').
  spawn(
      'C:\\WINDOWS\\System32\\WindowsPowerShell\\v1.0\\powershell',
      [
        '-NoProfile',
        '-NonInteractive',
        '–ExecutionPolicy',
        'Bypass',
        '-EncodedCommand',
        Buffer.from('Start "https://angular.io/api?query=asyncpipe"', 'utf16le').toString('base64'),  // 'UwB0AGEAcgB0ACAAIgBoAHQAdABwAHMAOgAvAC8AYQBuAGcAdQBsAGEAcgAuAGkAbwAvAGEAcABpAD8AcQB1AGUAcgB5AD0AYQBzAHkAbgBjAHAAaQBwAGUAIgA=',
      ],
      {
        windowsVerbatimArguments: true,
      });
proc.unref();
process.exit(0);

[alan-agius4]

Thanks @gkalpak for taking a look at this 😁