System.Filepath: Add to_slash() and from_slash()

autoload/vital/__vital__/System/Filepath.vim

@@ -14,6 +14,27 @@ let s:is_mac = !s:is_windows && !s:is_cygwin
  \  (!isdirectory('/proc') && executable('sw_vers')))
 let s:is_case_tolerant = filereadable(expand('<sfile>:r') . '.VIM')
 
+if s:is_windows
+ function! s:to_slash(path) abort
+ return tr(a:path, '\', '/')
+ endfunction
+else
+ function! s:to_slash(path) abort
+ return a:path
+ endfunction
+endif
+
+if s:is_windows
+ function! s:from_slash(path) abort
+ return tr(a:path, '/', '\')
+ endfunction
+else
+ function! s:from_slash(path) abort
+ return a:path
+ endfunction
+endif
+
+
 " Get the directory separator.
 function! s:separator() abort
  return fnamemodify('.', ':p')[-1 :]

doc/vital/System/Filepath.txt

@@ -21,6 +21,29 @@ INTERFACE *Vital.System.Filepath-interface*
 ------------------------------------------------------------------------------
 FUNCTIONS *Vital.System.Filepath-functions*
 
+to_slash({path}) *Vital.System.Filepath.to_slash()*
+ Use when you quote path string for scripting languages, without
+ worrying about the runtime operating system is if windows or not.
+
+ e.g.
+>
+ let code = printf(
+ \ '(neoclojure-init "%s")',
+ \ shellescape(s:F.to_slash(path)))
+ ..
+ let path = s:F.from_slash(
+ \ s:get_path_like_string_from_something())
+<
+
+ This function intentionally ignores 'shellslash' option, so that you
+ can simply use this function for path string not only from Vim but
+ also from others, such as environment vars, problem output, or really
+ anything.
+ See also: |Vital.System.Filepath.from_slash()|
+
+from_slash({path}) *Vital.System.Filepath.from_slash()*
+ This is opposite to |Vital.System.Filepath.to_slash()|. See its doc.
+
 separator() *Vital.System.Filepath.separator()*
  Return OS related directory separator as string.
  This returns "/" on non-Windows, or Windows and |'shellslash'| is on.

test/System/Filepath.vimspec

@@ -8,6 +8,27 @@ Describe System.Filepath
  let is_case_sensitive_file_system = !(isdirectory(tolower(g:root)) && isdirectory(toupper(g:root)))
  End
 
+ Describe .to_slash()
+ It converts / to \ only when it's necessary
+ Assert Equals('a/b', FP.to_slash('a/b'))
+ if has('win32') || has('win64')
+ Assert Equals('a/b', FP.to_slash('a\b'))
+ else
+ Assert Equals('a\b', FP.to_slash('a\b'))
+ endif
+ End
+ End
+
+ Describe .from_slash()
+ It converts \ to / only when it's necessary
+ if has('win32') || has('win64')
+ Assert Equals('a\b', FP.from_slash('a/b'))
+ else
+ Assert Equals('a/b', FP.from_slash('a/b'))
+ endif
+ End
+ End
+
  Describe .is_absolute()
  if !s:is_windows
  It returns TRUE if {path} is an absolute path