[ Summary ] Fix a process fork issue on Windows

[zhanghuabin]

[ Root Cause ]

1. There has no clojure script on Windows, the Clojure CLI is a PowerShell Module in windows, which cannot be called as a script directly.
2. Therefore, I make a .bat or .cmd to execute a PowerShell command.
3. After adding this .bat file to PATH, lein-tools-deps still cannot work, because the process created by (shell/sh "clojure" "-Sdescribe") cannot find either clojure.bat or clojure.cmd in PATH.

[Solution/Workaround ]
(shell/sh "cmd" "/c" "clojure" "-Sdescribe") work well for both the 'clojure' script file in PATH and custom path from clojure-executables.

[ Result ]
I test these two snippets in REPL:

(if (.startsWith (System/getProperty "os.name") "Windows")
  (shell/sh "cmd" "/c" "clojure" "-Sdescribe")
  (shell/sh "clojure" "-Sdescribe"))

(if (.startsWith (System/getProperty "os.name") "Windows")
  (shell/sh "cmd" "/c" "path/to/clojure.cmd" "-Sdescribe")
  (shell/sh "/path/to/clojure.cmd" "-Sdescribe"))

[hlolli]

Tested this PR, and this is what I get

 lein deps
clojure.lang.ExceptionInfo: Unable to locate Clojure's edn files
{:exit 1, :out "", :err "'clojure' is not recognized as an internal or external command,\r\noperable program or batch file.\r\n"}
 at lein_tools_deps.env$scrape_clojure_env.invokeStatic (env.clj:38)
    lein_tools_deps.env$scrape_clojure_env.invoke (env.clj:27)
    clojure.lang.AFn.applyToHelper (AFn.java:154)
    clojure.lang.AFn.applyTo (AFn.java:144)
    clojure.core$apply.invokeStatic (core.clj:665)
    clojure.core$memoize$fn__6862.doInvoke (core.clj:6353)
    clojure.lang.RestFn.invoke (RestFn.java:408)
    lein_tools_deps.plugin$apply_middleware.invokeStatic (plugin.clj:25)
    lein_tools_deps.plugin$apply_middleware.invoke (plugin.clj:17)
    lein_tools_deps.plugin$resolve_dependencies_with_deps_edn.invokeStatic (plugin.clj:47)
    lein_tools_deps.plugin$resolve_dependencies_with_deps_edn.invoke (plugin.clj:34)
    clojure.lang.Var.invoke (Var.java:384)
    leiningen.core.project$apply_middleware.invokeStatic (project.clj:817)
    leiningen.core.project$apply_middleware.invoke (project.clj:810)
    clojure.lang.ArrayChunk.reduce (ArrayChunk.java:58)
    clojure.core.protocols$fn__8139.invokeStatic (protocols.clj:136)
    clojure.core.protocols/fn (protocols.clj:124)
    clojure.core.protocols$fn__8099$G__8094__8108.invoke (protocols.clj:19)
    clojure.core.protocols$seq_reduce.invokeStatic (protocols.clj:31)
    clojure.core.protocols$fn__8131.invokeStatic (protocols.clj:75)
    clojure.core.protocols/fn (protocols.clj:75)
    clojure.core.protocols$fn__8073$G__8068__8086.invoke (protocols.clj:13)
    clojure.core$reduce.invokeStatic (core.clj:6828)
    clojure.core$reduce.invoke (core.clj:6810)
    leiningen.core.project$apply_middleware.invokeStatic (project.clj:812)
    leiningen.core.project$apply_middleware.invoke (project.clj:810)
    leiningen.core.project$activate_middleware.invokeStatic (project.clj:844)
    leiningen.core.project$activate_middleware.invoke (project.clj:840)
    leiningen.core.project$init_project.invokeStatic (project.clj:986)
    leiningen.core.project$init_project.invoke (project.clj:974)
    leiningen.core.project$read.invokeStatic (project.clj:1057)
    leiningen.core.project$read.invoke (project.clj:1054)
    leiningen.core.project$read.invokeStatic (project.clj:1058)
    leiningen.core.project$read.invoke (project.clj:1054)
    leiningen.core.main$_main$fn__6681.invoke (main.clj:447)
    leiningen.core.main$_main.invokeStatic (main.clj:442)
    leiningen.core.main$_main.doInvoke (main.clj:439)
    clojure.lang.RestFn.applyTo (RestFn.java:137)
    clojure.lang.Var.applyTo (Var.java:705)
    clojure.core$apply.invokeStatic (core.clj:665)
    clojure.main$main_opt.invokeStatic (main.clj:491)
    clojure.main$main_opt.invoke (main.clj:487)
    clojure.main$main.invokeStatic (main.clj:598)
    clojure.main$main.doInvoke (main.clj:561)
    clojure.lang.RestFn.applyTo (RestFn.java:137)
    clojure.lang.Var.applyTo (Var.java:705)
    clojure.main.main (main.java:37)

[hlolli]

Perhaps it's because currently, clojure isn't a binary on the path, but a powershell function

PS C:\Users\User\Documents\panaeolus> Get-Command clojure

CommandType     Name                                               Version    Source
-----------     ----                                               -------    ------
Alias           clojure -> Invoke-Clojure                          1.10.1.447 ClojureTools


PS C:\Users\User\Documents\panaeolus> Get-Command Invoke-Clojure

CommandType     Name                                               Version    Source
-----------     ----                                               -------    ------
Function        Invoke-Clojure                                     1.10.1.447 ClojureTools

[RickMoynihan]

Perhaps it's because currently, clojure isn't a binary on the path, but a powershell function

@hlolli isn't this what @zhanghuabin is saying you need to do here:

i.e. that you need to wrap the powershell command with a .bat or .cmd on the path? (I've not used windows for over a decade so I don't know; just guessing)

If you can confirm this works, I'd be happy to merge this PR if it would also include instructions for how to make this work on windows.

[RickMoynihan]

Note this issue also seems related: #85

If the windows users here can assemble a PR with all the changes required to work on windows with any required additional steps in the README, and can perhaps review it amongst yourselves then I'll consider merging.