Swift can't find its subcommands from within emacs on Windows

[dabrahams]

Description

strangely, if I do M-! (cmd-shift-1) and enter this shell command in Emacs on windows:

where swift && where swift-test.exe && swift test --pkg-config-path .

I get this output

C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr\bin\swift.exe
C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr\bin\swift-test.exe
error: unknown or missing subcommand 'swift-test.exe'

in other words, it can run swift and swift-test directly, but cannot run swift-test through swift. Git, which is similarly structured, doesn't show the same problem.. Suggests there might be something wrong with the way swift is invoking subcommands, although this works fine from a cmd shell.

compnerd.org Swift version 5.9-dev (LLVM 466a716843b7efb, Swift 39bac1c)
Target: x86_64-unknown-windows-msvc

[dabrahams]

I think Swift is treating the Path environment variable case-sensitively, because from within Emacs on my machine it is spelled PATH and not Path. When I change it to Path, things work.

[s-k]

I believe, I have encountered the same bug. When I specify a swift run command in a Makefile on Windows, executing make produces error: unknown or missing subcommand 'swift-run.exe'.

Edit: The same happens when swift run is run from a .bat file.

@dabrahams What exactly did you do to make it work in Emacs?

[dabrahams]

@dabrahams What exactly did you do to make it work in Emacs?

Exactly this.

[s-k]

@dabrahams I‘m sorry. I get a 404 error when I click on your link.

[dabrahams]

My apologies, I didn't realize the repo was private. I was pointing at this code:

;;; Workaround https://debbugs.gnu.org/cgi/bugreport.cgi?bug=67540
(defun unsetenv (var-name)
  (let ((current-prefix-arg '(4)))
	(funcall-interactively 'setenv var-name nil)))

(when (eq system-type 'windows-nt)
  (dolist (v '("Path" "ComSpec"))
          (let ((x (getenv v)))
               (unsetenv (upcase v))
               (setenv v x))))