npm:aws-cdk init throws TypeError (windows only)

[GJZwiers]

deno run -A npm:aws-cdk init --language typescript

Applying project template app for typescript
TypeError [ERR_INVALID_ARG_TYPE]" argument must be of type number. Received undefined
    at __node_internal_ (https://deno.land/std@0.165.0/node/internal/validators.mjs:112:15)
    at parseFileMode (https://deno.land/std@0.165.0/node/internal/validators.mjs:49:3)
    at Object.chmod (https://deno.land/std@0.165.0/node/_fs/_fs_chmod.ts:8:12)
    at Object.chmod (file:///C:/Users/GJZwiers/AppData/Local/deno/npm/registry.npmjs.org/node_modules/graceful-fs/polyfills.js:252:19)l-fs/polyfills.js:252:19)                                                                                     /lib/copy/copy.js:131:13)
    at setDestMode (file:///C:/Users/GJZwiers/AppData/Local/deno/npm/registry.npmjs.org/node_modules/fs-extray.js:98:12/lib/copy/copy.js:131:13)                                                                                     fs.js:186:16
    at file:///C:/Users/GJZwiers/AppData/Local/deno/npm/registry.npmjs.org/node_modules/fs-extra/lib/copy/copy.js:98:12
    at file:///C:/Users/GJZwiers/AppData/Local/deno/npm/registry.npmjs.org/node_modules/graceful-fs/graceful-fs.js:186:16
    at https://deno.land/std@0.165.0/node/_fs/_fs_common.ts:230:31
    at https://deno.land/std@0.165.0/node/_fs/_fs_copy.ts:30:49

deno --version

deno 1.28.1 (release, x86_64-pc-windows-msvc)
v8 10.9.194.1
typescript 4.8.3

Edit: Only happens on Windows

[cjihrig]

Since this is Windows only, would you care to help debug or fix, @GJZwiers ?

[GJZwiers]

I can do some debugging! Is there a way to make my local deno binary/cargo build work with my local copy of std, so I can test some changes?

[cjihrig]

Is there a way to make my local deno binary/cargo build work with my local copy of std, so I can test some changes?

Yep! Here is what I use:

DENO_NODE_COMPAT_URL='file:///path/to/your/std/' /path/to/cli/deno run -A --unstable your_script.js

[GJZwiers]

The issue seems to be that the mode parameter passed to chmod function is null and no default value def is set in parseFileMode, causing an assignment to undefined. Deeper in the call stack I found that mode is set to 0 but when it goes through the node compat layer it changes to null somewhere. This happens in an internal node_modules folder that is maybe created on the fly (because it doesn't exist in my filesystem)?

A potential fix for this issue could be to pass a value for def in the chmod function (although the code will still throw with another error because it then calls Deno.chmod which is not supported on Windows at the moment (denoland/deno#4357)).

[cjihrig]

Thanks for taking a look. Interestingly, Node does not pass a default value to here either.

[GJZwiers]

Based on denoland/deno#17841 I made a simpler reproduction for the error:

import * as fs from "npm:fs-extra";

await fs.copy("foo.js", "bar.js");

[PolarETech]

In fs-extra, file permission is also copied when copying a file.

https://github.com/jprichardson/node-fs-extra/blob/f3a7f0beeb5858c628b10010ad819c813c7f3565/lib/copy/copy.js#L102
https://github.com/jprichardson/node-fs-extra/blob/f3a7f0beeb5858c628b10010ad819c813c7f3565/lib/copy/copy.js#L134

The mode of the source file is got by fs.stat or fs.lstat.

https://github.com/jprichardson/node-fs-extra/blob/f3a7f0beeb5858c628b10010ad819c813c7f3565/lib/copy/copy.js#L67

With Node.js we can get the mode value of the file, even on Windows, but with Deno it returns null.
This is why the mode value passed to the chmod function is null.

[PolarETech]

fs.stat and fs.lstat use Deno.stat and Deno.lstat.

https://github.com/denoland/deno_std/blob/1cda9238eaa24b26fd34e1d5963906ed1bcdd301/node/_fs/_fs_stat.ts#L273
https://github.com/denoland/deno_std/blob/1cda9238eaa24b26fd34e1d5963906ed1bcdd301/node/_fs/_fs_lstat.ts#L40

It would be nice if functions like Deno.stat would support for the mode property on Windows, but is this difficult due to Rust's std::fs reasons?

A workaround might be to ignore parseFileMode as well, since Deno.chmod is not available on Windows anyway.

https://github.com/denoland/deno_std/blob/1cda9238eaa24b26fd34e1d5963906ed1bcdd301/node/_fs/_fs_chmod.ts#L9-L27

[kt3k]

skipping parseFileMode on windows makes sense to me.