Prepare for fern-plugin-xxxxx

autoload/fern/helper/async.vim

@@ -23,6 +23,7 @@ function! s:async_redraw() abort dict
         \ )
         \})
         \.then({ v -> fern#internal#buffer#replace(helper.bufnr, v) })
+        \.then({ -> fern#hook#emit('viewer:redraw', helper) })
         \.finally({ -> Profile() })
 endfunction
 let s:async.redraw = funcref('s:async_redraw')

autoload/fern/internal/core.vim

@@ -14,8 +14,10 @@ function! fern#internal#core#new(url, provider, ...) abort
         \ 'comparator': g:fern#comparator,
         \}, a:0 ? a:1 : {},
         \)
+  let scheme = fern#fri#parse(a:url).scheme
   let root = fern#internal#node#root(a:url, a:provider)
   let fern = {
+        \ 'scheme': scheme,
         \ 'source': s:CancellationTokenSource.new(),
         \ 'provider': a:provider,
         \ 'renderer': s:get_renderer(options.renderer),

autoload/fern/internal/viewer.vim

@@ -104,7 +104,9 @@ endfunction
 
 function! s:BufReadCmd() abort
   let helper = fern#helper#new()
+  setlocal filetype=fern
   call helper.fern.renderer.syntax()
+  call fern#hook#emit('renderer:syntax', helper)
   let root = helper.sync.get_root_node()
   let cursor = get(b:, 'fern_cursor', getcurpos())
   call s:Promise.resolve()
@@ -119,4 +121,5 @@ endfunction
 function! s:ColorScheme() abort
   let helper = fern#helper#new()
   call helper.fern.renderer.highlight()
+  call fern#hook#emit('renderer:highlight', helper)
 endfunction

autoload/vital/_fern/Async/CancellationTokenSource.vim

@@ -82,5 +82,5 @@ function! s:_unlink(source) abort
 endfunction
 
 function! s:_throw(exception) abort
-  throw a:exception
+  throw substitute(a:exception, '^Vim(.*):', '', '')
 endfunction

autoload/vital/_fern/Async/Promise/Process.vim

@@ -92,5 +92,5 @@ endfunction
 
 function! s:_on_cancel(ns, ...) abort
   call a:ns.job.stop()
-  call a:ns.reject(s:CancellationToken.CancellationError)
+  call a:ns.reject(s:CancellationToken.CancelledError)
 endfunction

autoload/vital/fern.vim

@@ -149,7 +149,7 @@ function! s:_import(name) abort dict
     call module._vital_created(module)
   endif
   let export_module = filter(copy(module), 'v:key =~# "^\\a"')
-  " Cache module before calling module.vital_loaded() to avoid cyclic
+  " Cache module before calling module._vital_loaded() to avoid cyclic
   " dependences but remove the cache if module._vital_loaded() fails.
   " let s:loaded[a:name] = export_module
   let s:loaded[a:name] = export_module
@@ -167,30 +167,51 @@ let s:Vital._import = function('s:_import')
 
 function! s:_format_throwpoint(throwpoint) abort
   let funcs = []
-  let stack = matchstr(a:throwpoint, '^function \zs.*\ze, line \d\+$')
+  let stack = matchstr(a:throwpoint, '^function \zs.*, .\{-} \d\+$')
   for line in split(stack, '\.\.')
-    let m = matchlist(line, '^\%(<SNR>\(\d\+\)_\)\?\(.\+\)\[\(\d\+\)\]$')
-    if empty(m)
-      call add(funcs, line)
-      continue
-    endif
-    let [sid, name, lnum] = m[1:3]
-    let attr = ''
-    if !empty(sid)
-      let name = printf('<SNR>%d_%s', sid, name)
+    let m = matchlist(line, '^\(.\+\)\%(\[\(\d\+\)\]\|, .\{-} \(\d\+\)\)$')
+    if !empty(m)
+      let [name, lnum, lnum2] = m[1:3]
+      if empty(lnum)
+        let lnum = lnum2
+      endif
+      let info = s:_get_func_info(name)
+      if !empty(info)
+        let attrs = empty(info.attrs) ? '' : join([''] + info.attrs)
+        let flnum = info.lnum == 0 ? '' : printf(' Line:%d', info.lnum + lnum)
+        call add(funcs, printf('function %s(...)%s Line:%d (%s%s)',
+        \        info.funcname, attrs, lnum, info.filename, flnum))
+        continue
+      endif
     endif
-    let file = s:_get_file_by_func_name(name)
-    call add(funcs, printf('function %s(...)%s Line:%d (%s)', name, attr, lnum, file))
+    " fallback when function information cannot be detected
+    call add(funcs, line)
   endfor
   return join(funcs, "\n")
 endfunction
 
-function! s:_get_file_by_func_name(name) abort
-  let body = execute(printf('verbose function %s', a:name))
+function! s:_get_func_info(name) abort
+  let name = a:name
+  if a:name =~# '^\d\+$'  " is anonymous-function
+    let name = printf('{%s}', a:name)
+  elseif a:name =~# '^<lambda>\d\+$'  " is lambda-function
+    let name = printf("{'%s'}", a:name)
+  endif
+  if !exists('*' . name)
+    return {}
+  endif
+  let body = execute(printf('verbose function %s', name))
   let lines = split(body, "\n")
   let signature = matchstr(lines[0], '^\s*\zs.*')
-  let file = matchstr(lines[1], '^\t\%(Last set from\|.\{-}:\)\s*\zs.*$')
-  return substitute(file, '[/\\]\+', '/', 'g')
+  let [_, file, lnum; __] = matchlist(lines[1],
+  \   '^\t\%(Last set from\|.\{-}:\)\s*\zs\(.\{-}\)\%( \S\+ \(\d\+\)\)\?$')
+  return {
+  \   'filename': substitute(file, '[/\\]\+', '/', 'g'),
+  \   'lnum': 0 + lnum,
+  \   'funcname': a:name,
+  \   'arguments': split(matchstr(signature, '(\zs.*\ze)'), '\s*,\s*'),
+  \   'attrs': filter(['dict', 'abort', 'range', 'closure'], 'signature =~# (").*" . v:val)'),
+  \ }
 endfunction
 
 " s:_get_module() returns module object wihch has all script local functions.

autoload/vital/fern.vital

@@ -1,5 +1,5 @@
 fern
-8043f4d0f577ffb654cab9cfe629312b36c5342d
+80887bd366c925887a40829eae73e86d7bb63ecc
 
 App.Spinner
 Async.CancellationTokenSource

doc/fern-develop.txt

@@ -15,6 +15,7 @@ RENDERER				|fern-develop-renderer|
 SCHEME					|fern-develop-scheme|
   PROVIDER				|fern-develop-scheme-provider|
   MAPPING				|fern-develop-scheme-provider|
+HOOK					|fern-develop-hook|
 HELPER					|fern-develop-helper|
 LOGGER					|fern-develop-logger|
 UTILITY					|fern-develop-utility|
@@ -303,6 +304,7 @@ VARIABLE				*fern-develop-helper-variable*
 .fern
 	A fern instance which has the following attributes:
 
+	"scheme"	A scheme name used to determine "provider"
 	"source"	A cancellation token source to cancel requests
 	"provider"	A provider instance for the fren tree
 	"renderer"	A renderer instance to sort nodes
@@ -500,6 +502,29 @@ Following methods are executed asynchronously and return a promise.
 	It is used to collapse modified nodes to solve issue #103.
 
 
+=============================================================================
+HOOK						*fern-develop-hook*
+
+Following hook will be emitted by |fern#hook#emit()| from fern itself.
+
+"renderer:syntax" ({helper})
+	Called when fern renderer has register its syntax.
+	The {helper} is a helper instance described in |fern-develop-helper|.
+
+"renderer:highlight" ({helper})
+	Called when fern renderer has register its highlight.
+	The {helper} is a helper instance described in |fern-develop-helper|.
+
+"viewer:redraw" ({helper})
+	Called when fern viewer has redrawed.
+	The {helper} is a helper instance described in |fern-develop-helper|.
+
+"viewer:ready" ({helper})
+	Called when fern viewer has ready, mean that the buffer has opened and
+	all content has rendererd.
+	The {helper} is a helper instance described in |fern-develop-helper|.
+
+
 =============================================================================
 LOGGER						*fern-develop-logger*
 

plugin/fern.vim

@@ -1,7 +1,8 @@
-if exists('g:fern_loaded')
+if exists('g:loaded_fern')
   finish
 endif
-let g:fern_loaded = 1
+let g:loaded_fern = 1
+let g:fern_loaded = 1 " Obsolete: For backward compatibility
 
 command! -bar -nargs=*
       \ -complete=customlist,fern#internal#command#fern#complete
@@ -30,4 +31,8 @@ augroup fern_internal
   autocmd! *
   autocmd BufReadCmd fern://* ++nested call s:BufReadCmd()
   autocmd SessionLoadPost fern://* ++nested call s:BufReadCmd()
+  autocmd User FernInit ++once :
 augroup END
+
+" Tell 3rd parties that fern has initialized
+doautocmd <nomodeline> User FernInit

test/fern/internal/core.vimspec

@@ -9,6 +9,7 @@ Describe fern#internal#core
   Describe #new()
     It returns a fern instance of given url and provider
       let fern = fern#internal#core#new('debug:///', provider)
+      Assert KeyExists(fern, 'scheme')
       Assert KeyExists(fern, 'source')
       Assert KeyExists(fern, 'provider')
       Assert KeyExists(fern, 'comparator')