Improve on preconfigured callbacks

autoload/langserver/callbacks.vim

@@ -1,3 +1,16 @@
+function! s:check_extra_callbacks(last_topic) abort
+  echom 'Checking custom callbacks'
+  let l:custom_callbacks = langserver#default#extension_callbacks()
+  echom 'Custom callbacks are: ' . string(l:custom_callbacks)
+  if has_key(l:custom_callbacks, a:last_topic)
+    call langserver#log#log('info', 'Calling custom callback for: ' . a:last_topic, v:true)
+    return l:custom_callbacks[a:last_topic]
+  else
+    call langserver#log#log('warning', 'No callback registered for: ' . a:last_topic, v:true)
+    return v:false
+  endif
+endfunction
+
 function! langserver#callbacks#on_stdout(id, data, event) abort
   echom 'LSP STDOUT(' . a:id . '): ' . string(a:data)
 endfunction
@@ -12,7 +25,15 @@ endfunction
 
 function! langserver#callbacks#on_notification(id, data, event) abort
   if a:event ==? 'on_request'
-    call langserver#extension#command#callback(a:id, a:data, a:event)
+    let l:last_topic = a:data['request']['method']
+
+    let l:ExtraCallbacks = s:check_extra_callbacks(l:last_topic)
+
+    if type(l:ExtraCallbacks) == type(function('tr'))
+      let l:result = call(l:ExtraCallbacks, [a:id, a:data, a:event])
+    else
+      call langserver#extension#command#callback(a:id, a:data, a:event)
+    endif
   elseif a:event ==? 'on_notification'
     if has_key(a:data, 'response')
       call langserver#log#response(a:id, a:data, a:event)
@@ -32,7 +53,12 @@ function! langserver#callbacks#on_notification(id, data, event) abort
       elseif l:last_topic ==? 'workspace/symbol'
         call langserver#symbol#workspace#callback(a:id, a:data, a:event)
       else
-        call langserver#log#log('warning', 'No callback registered for: ' . l:last_topic, v:true)
+        " Check if any extra callbacks exist.
+        let l:ExtraCallbacks = s:check_extra_callbacks(l:last_topic)
+
+        if type(l:ExtraCallbacks) == type(function('tr'))
+          let l:result = call(l:ExtraCallbacks, [a:id, a:data, a:event])
+        endif
       endif
     elseif has_key(a:data, 'request')
       echom 'notification...'
@@ -42,7 +68,8 @@ function! langserver#callbacks#on_notification(id, data, event) abort
 
     if langserver#client#is_error(a:data.response)
       call langserver#log#log('debug',
-            \ 'lsp('.a:id.'):notification:notification error receieved for '.a:data.request.method,
+            \ 'lsp('.a:id.'):notification:notification error receieved for '.a:data.request.method .
+            \ ': ' . string(a:data),
             \ v:true,
             \ )
     else

autoload/langserver/default.vim

@@ -34,18 +34,23 @@ function! langserver#default#cmd(...) abort
 endfunction
 
 function! langserver#default#extension_callbacks(...) abort
-  if a:0 > 0
-    let l:filetype_key = langserver#util#get_executable_key(a:1)
-  else
-    let l:filetype_key = langserver#util#get_executable_key(&filetype)
-  endif
+  try
+    if a:0 > 0
+      let l:filetype_key = langserver#util#get_executable_key(a:1)
+    else
+        let l:filetype_key = langserver#util#get_executable_key(&filetype)
+    endif
+  catch /.*Unsupported filetype.*/
+    return {}
+  endtry
 
   if has_key(g:langserver_executables, l:filetype_key)
     let l:location = s:preconfigured_location . g:langserver_executables[l:filetype_key]['name']
     let l:file_to_source = l:location . s:callbacks_name
     if isdirectory(l:location) && filereadable(l:file_to_source)
       execute('source ' . l:file_to_source)
       let l:subbed = substitute(g:langserver_executables[l:filetype_key]['name'], '/', '_', 'g')
+      let l:subbed = substitute(l:subbed, '-', '_', 'g')
       return Preconfigured_{l:subbed}()
     else
       return {}

autoload/langserver/log.vim

@@ -110,10 +110,10 @@ endfunction
 function! langserver#log#callback(id, data, event) abort
   call langserver#log#log('debug',
         \ printf('(%3s:%15s): %s',
-        \ a:id,
-        \ a:event,
-        \ string(a:data)
-        \ ),
+          \ a:id,
+          \ a:event,
+          \ string(a:data)
+          \ ),
         \ v:false
         \ )
 endfunction

tests/test_defaults.vader

@@ -81,4 +81,17 @@ Execute (Getting predefined functions and passing args):
 
   let g:langserver_executables = g:__temp_exec
 
+Execute (Returns empty dictionary if unknown filetype):
+  let g:__temp_exec = get(g:, 'langserver_executables', {})
+
+  let g:langserver_executables = {
+        \ 'testing': {
+              \ 'name': 'test/test',
+              \ 'cmd': ['echo', '"hello"'],
+              \ },
+        \ }
 
+  let test_functions = langserver#default#extension_callbacks('foobar')
+  AssertEqual {}, test_functions
+
+  let g:langserver_executables = g:__temp_exec