Why does`deno run` not use `jsr:@webpod/zx`?

[tcely]

~/.cache $ DEBUG_ZX_SH=true zx_run 'jsr:@webpod/zx' <<<'console.log( await $({ verbose: true })`echo Hello world! | xargs -t -n 1 echo` )'
+ install -d -m 00775 /data/data/com.termux/files/../cache/zx
+ cd /data/data/com.termux/files/../cache/zx
+ zx=jsr:@webpod/zx
+ shift
+ exec deno run --no-config --allow-read=/data/data/com.termux/files/usr/bin/bash --allow-read=/data/data/com.termux/files/files/home --allow-read=/data/data/com.termux/files/../cache --ignore-read --allow-write=/data/data/com.termux/files/../cache/zx --allow-env --allow-run --allow-sys=homedir,uid,gid,cpus -- jsr:@webpod/zx

~/.cache $ DEBUG_ZX_SH=true zx_run 'npm:zx' <<<'console.log( await $({ verbose: true })`echo Hello world! | xargs -t -n 1 echo` )'
+ install -d -m 00775 /data/data/com.termux/files/../cache/zx
+ cd /data/data/com.termux/files/../cache/zx
+ zx=npm:zx
+ shift
+ exec deno run --no-config --allow-read=/data/data/com.termux/files/usr/bin/bash --allow-read=/data/data/com.termux/files/files/home --allow-read=/data/data/com.termux/files/../cache --ignore-read --allow-write=/data/data/com.termux/files/../cache/zx --allow-env --allow-run --allow-sys=homedir,uid,gid,cpus -- npm:zx
$ echo Hello world! | xargs -t -n 1 echo
echo Hello
Hello
echo 'world!'
world!
ProcessOutput {
  stdout: 'Hello\nworld!\n',
  stderr: "echo Hello\necho 'world!'\n",
  signal: null,
  exitCode: 0,
  duration: 124
}

Only when using 'npm:zx' does the output show up. ¹

Am I doing anything wrong here? Why would it be different?

---

I looked into this some more. isMain returning false is the reason.

These are the valid cases it should accept from debugging deno run:

• DEBUG RS - deno::worker:80 - main_module jsr:@webpod/zx/./cli
• DEBUG RS - deno::worker:80 - main_module jsr:@webpod/zx/cli
• DEBUG RS - deno::worker:80 - main_module jsr:@webpod/zx/.
• DEBUG RS - deno::worker:80 - main_module jsr:@webpod/zx

As you can see, when using jsr:@webpod/zx the main module is not translated to a local file path.

In addition to that problem, the value for process.argv[1] is constructed using the absolute path to the current working directory plus $deno$node.mjs. Which, as far as I could determine, is never actually on the filesystem.

In short, the current strategy of isMain is insufficient.

zx/src/cli.ts

Lines 262 to 274 in 1ca9270

	export function isMain(
	metaurl: string = import.meta.url,
	scriptpath: string = process.argv[1]
	): boolean {
	if (metaurl.startsWith('file:')) {
	const modulePath = url.fileURLToPath(metaurl).replace(/\.\w+$/, '')
	const mainPath = fs.realpathSync(scriptpath).replace(/\.\w+$/, '')
	return mainPath === modulePath
	}
	return false
	}

zx/src/cli.ts

Lines 57 to 66 in 1ca9270

	isMain() &&
	main().catch((err) => {
	if (err instanceof ProcessOutput) {
	console.error('Error:', err.message)
	} else {
	console.error(err)
	}
	process.exitCode = 1
	})

Footnotes

1. https://gist.github.com/tcely/a16186fdd9e47189e31c8cd9c5fbfea1 ↩