Closure compiler does not work on Windows at least if path contains UTF-8 characters

If an input file name contains non-7bit-ASCII characters in it, Closure fails to operate.

STR:

1. Install Closure compiler to directory “☃äö Ć € 🦠”. (not mandatory, but for good measure to see if any issues arise from that)
2. Pass an input file “☃äö Ć € 🦠.js” to Closure compiler as --externs or --js.

Results in

C:\☃em sd äö Ć € 🦠\emsdk\emscripten\main> dir äö.js
 Volume in drive C has no label.
 Volume Serial Number is 8847-8E7D

 Directory of C:\☃em sd äö Ć € 🦠\emsdk\emscripten\main

03/16/2021  06:18 PM             3,472 äö.js
               1 File(s)          3,472 bytes
               0 Dir(s)  1,757,394,030,592 bytes free

C:\☃em sd äö Ć € 🦠\emsdk\emscripten\main> node_modules\.bin\google-closure-compiler --externs äö.js --js_output_file out.js --js a.js
[ '--externs', 'äö.js', '--js_output_file', 'out.js', '--js', 'a.js' ]
ERROR - [JSC_READ_ERROR] Cannot read file äö.js: äö.js

1 error(s), 0 warning(s)

C:\☃em sd äö Ć € 🦠\emsdk\emscripten\main> node_modules\.bin\google-closure-compiler --externs a.js --js_output_file out.js --js äö.js
[ '--externs', 'a.js', '--js_output_file', 'out.js', '--js', 'äö.js' ]
ERROR - [JSC_READ_ERROR] Cannot read file äö.js: äö.js

1 error(s), 0 warning(s)

1. Pass UTF-8 chars as output file :

C:\☃em sd äö Ć € 🦠\emsdk\emscripten\main> node_modules\.bin\google-closure-compiler --js a.js --js_output_file äää.js
[ '--js', 'a.js', '--js_output_file', 'äää.js' ]

C:\☃em sd äö Ć € 🦠\emsdk\emscripten\main> dir *.js
 Volume in drive C has no label.
 Volume Serial Number is 8847-8E7D

 Directory of C:\☃em sd äö Ć € 🦠\emsdk\emscripten\main

03/16/2021  06:18 PM             3,472 a.js
03/16/2021  06:24 PM             5,595 äää.js
               2 File(s)          9,067 bytes
               0 Dir(s)  1,757,393,338,368 bytes free

[brad4d]

I’m afraid we’re just really not motivated to spend development effort on making non-ascii JS inputs work.

However, we’ll be happy to review and merge a PR if someone in the community would like to create one.

[Chris2011]

Is this related to this error, that I get for a file with a cyrillic filename?

Filename: наиывпишв.js

And here is my command: "C:\Users\Chris\.netbeans\minifierbeans\custom-packages\google-closure-compiler.cmd" "--compilation_level" "SIMPLE" "--language_in" "STABLE" "--language_out" "ECMASCRIPT_NEXT" "--js" "C:/Users/Chris/Documents/NetBeansProjects/HTML5Application/public_html/наиывпишв.js" "--js_output_file" "C:/Users/Chris/Documents/NetBeansProjects/HTML5Application/public_html/наиывпишв.min.js"

And here is the error:

Exception in thread "main" java.nio.file.InvalidPathException: Illegal char <?> at index 71: C:/Users/Chris/Documents/NetBeansProjects/HTML5Application/public_html/?????????.js
        at sun.nio.fs.WindowsPathParser.normalize(WindowsPathParser.java:182)
        at sun.nio.fs.WindowsPathParser.parse(WindowsPathParser.java:153)
        at sun.nio.fs.WindowsPathParser.parse(WindowsPathParser.java:77)
        at sun.nio.fs.WindowsPath.parse(WindowsPath.java:92)
        at sun.nio.fs.WindowsFileSystem.getPath(WindowsFileSystem.java:229)
        at java.nio.file.Path.of(Path.java:147)
        at java.nio.file.Paths.get(Paths.java:69)
        at com.google.javascript.jscomp.CommandLineRunner.findJsFiles(CommandLineRunner.java:2130)
        at com.google.javascript.jscomp.CommandLineRunner.access$000(CommandLineRunner.java:134)
        at com.google.javascript.jscomp.CommandLineRunner$Flags.getMixedJsSources(CommandLineRunner.java:1226)
        at com.google.javascript.jscomp.CommandLineRunner.initConfigFromFlags(CommandLineRunner.java:1605)
        at com.google.javascript.jscomp.CommandLineRunner.<init>(CommandLineRunner.java:1446)
        at com.google.javascript.jscomp.CommandLineRunner.main(CommandLineRunner.java:2214)

Happens in my NetBeans plugin https://github.com/Chris2011/minifierbeans/issues/90