Refactor LSP custom request handling

test/lsp/test_lsp_custom_request.vader

@@ -7,13 +7,15 @@ Before:
   let g:callback_result = 0
   let g:conn_id = -1
   let g:executable = 'ccls'
+  let g:executable_or_address = ''
   let g:linter_name = 'ccls'
   let g:magic_number = 42
-  let g:message = -1
+  let g:message_list = []
   let g:message_id = 1
   let g:method = '$ccls/call'
   let g:parameters = {}
-  let g:project = '/project/root'
+  let g:project_root = '/project/root'
+  let g:response = ''
   let g:return_value = -1
 
   let g:linter_list = [{
@@ -21,7 +23,7 @@ Before:
   \   'lint_file': 0,
   \   'language': 'cpp',
   \   'name': g:linter_name,
-  \   'project_root': {b -> g:project},
+  \   'project_root': {b -> g:project_root},
   \   'aliases': [],
   \   'language_callback': {b -> 'cpp'},
   \   'read_buffer': 1,
@@ -34,10 +36,20 @@ Before:
     return 'Content-Length: ' . strlen(l:body) . "\r\n\r\n" . l:body
   endfunction
 
-  " Register the server with given executable or address
-  function! InitServer(executable_or_address) abort
-    let g:conn_id = ale#lsp#Register(a:executable_or_address, g:project, {})
+  " Replace the StartLSP function to mock an LSP linter
+  function! ale#lsp_linter#StartLSP(buffer, linter, Callback) abort
+    let g:conn_id = ale#lsp#Register(g:executable_or_address, g:project_root, {})
+    call ale#lsp#MarkDocumentAsOpen(g:conn_id, a:buffer)
     call ale#lsp#HandleMessage(g:conn_id, Encode({'method': 'initialize'}))
+
+    let l:details = {
+    \ 'command': g:executable,
+    \ 'buffer': a:buffer,
+    \ 'connection_id': g:conn_id,
+    \ 'project_root': g:project_root,
+    \}
+
+    call ale#lsp_linter#OnInit(a:linter, l:details, a:Callback)
   endfunction
 
   " Dummy callback
@@ -52,25 +64,29 @@ Before:
 
   " Replace the Send function to mock an LSP linter
   function! ale#lsp#Send(conn_id, message) abort
-    let g:message = a:message
+    call add(g:message_list, a:message)
     return g:message_id
   endfunction
 
   " Code for a test case
   function! TestCase() abort
     " Test sending a custom request
-    let g:return_value = ale#lsp_linter#SendRequest(bufnr('%'), g:linter_name, g:method, g:parameters, function('Callback'))
+    let g:return_value = ale#lsp_linter#SendRequest(
+    \  bufnr('%'),
+    \  g:linter_name,
+    \  g:method,
+    \  g:parameters,
+    \  function('Callback'))
 
-    AssertEqual
-    \ 0,
-    \ g:return_value
-
-    AssertEqual
-    \ [0, g:method, g:parameters],
-    \ g:message
+    Assert index(g:message_list, [0, g:method, g:parameters]) >= 0
 
     " Mock an incoming response to the request
-    call ale#lsp#HandleMessage(g:conn_id, Encode({'id': g:message_id, 'jsonrpc': '2.0', 'result': {'value': g:magic_number}}))
+    let g:response = Encode({
+    \  'id': g:message_id,
+    \  'jsonrpc': '2.0',
+    \  'result': {'value': g:magic_number}
+    \ })
+    call ale#lsp#HandleMessage(g:conn_id, g:response)
 
     AssertEqual
     \ g:magic_number,
@@ -87,15 +103,15 @@ After:
   unlet! g:executable
   unlet! g:linter_name
   unlet! g:magic_number
-  unlet! g:message
+  unlet! g:message_list
   unlet! g:message_id
   unlet! g:method
   unlet! g:parameters
-  unlet! g:project
+  unlet! g:project_root
+  unlet! g:response
   unlet! g:return_value
 
   delfunction Encode
-  delfunction InitServer
   delfunction Callback
   delfunction TestCase
 
@@ -105,7 +121,7 @@ After:
 
 Given cpp(Empty cpp file):
 Execute(Test custom request to server identified by executable):
-  call InitServer(g:executable)
+  let g:executable_or_address = g:executable
   let g:linter_list[0].executable = {b -> g:executable}
   let g:linter_list[0].lsp = 'stdio'
 
@@ -113,7 +129,7 @@ Execute(Test custom request to server identified by executable):
 
 Given cpp(Empty cpp file):
 Execute(Test custom request to server identified by address):
-  call InitServer(g:address)
+  let g:executable_or_address = g:address
   let g:linter_list[0].address = {b -> g:address}
   let g:linter_list[0].lsp = 'socket'