Dependency resolution error with short file name on Windows

[ayame113]

Please refer to denoland/fresh#471 (comment).

This bug is caused by a combination of the following three conditions.

• cwd is set to a windows short pathname (using command prompt or cwd option of Deno.Command)
• deno.json exists
• There is an import-map with a relative path

How to reproduce the bug

Move to the Windows short file name (= 8.3 format) directory. (I had to use cmd instead of powershell for this.)

> dir /x
2023/05/26  15:32    <DIR>                       .
2023/05/09  08:52    <DIR>                       ..
2023/05/26  15:35    <DIR>          TESTDI~1     test dir # This means that the short filename alias for `test dir` is `TESTDI~1`.

> cd ../TESTDI~1

Create a file like this:

// deno.json
{
  "importMap": "./import-map.json"
}

// import-map.json
{
  "imports": {
    "@/": "./"
  }
}

// parent.ts
import "@/child.ts";
import "./child.ts";

// child.ts
console.log("hello from child.ts!");

Run deno info. Here the dependencies include two child.ts. I believe this is a bug.
Also, console.log is done twice when I run deno run.

> deno info parent.ts
local: C:\Users\ayame\work\TESTDI~1\parent.ts
emit: C:\Users\ayame\AppData\Local\deno\gen\file\C\Users\ayame\work\TESTDI~1\parent.ts.js
type: TypeScript
dependencies: 2 unique
size: 120B

file:///C:/Users/ayame/work/TESTDI~1/parent.ts (44B)
├── file:///C:/Users/ayame/work/test%20dir/child.ts (38B)
└── file:///C:/Users/ayame/work/TESTDI~1/child.ts (38B)

> deno run ./parent.ts
hello from child.ts!
hello from child.ts!

This is causing strange errors like the one described by denoland/fresh#471 (comment).

Another oddity about this bug is that if I remove the deno.json it works fine.
The result of deleting deno.json and running is below.

> deno info --import-map=import-map.json ./parent.ts
local: C:\Users\ayame\work\TESTDI~1\parent.ts
emit: C:\Users\ayame\AppData\Local\deno\gen\file\C\Users\ayame\work\TESTDI~1\parent.ts.js
type: TypeScript
dependencies: 1 unique
size: 82B

file:///C:/Users/ayame/work/TESTDI~1/parent.ts (44B)
├── file:///C:/Users/ayame/work/TESTDI~1/child.ts (38B)
└── file:///C:/Users/ayame/work/TESTDI~1/child.ts *

> deno run --import-map=import-map.json ./parent.ts
hello from child.ts!

I don't know how many people use Windows's short pathnames, but it's strange that the behavior changes depending on whether deno.json exists or not.