patch 9.0.1939: still a problem when processing LSP RPC requests

Problem:  still a problem when processing LSP RPC requests
Solution: When processing async LSP RPC requests, compare sequence
          numbers only in response messages

A LSP request message can be sent to the language server either
synchronously (ch_evalexpr) or asynchronously (ch_sendexpr). In both
cases, when looking for response messages by using the sequence number,
LSP requests messages from the language server with the same sequence
number should not be used. Patch 9.0.1927 fixed this issue for
synchronous requests. This PR fixes the issue for asynchronous requests
and adds additional tests.

closes: #13158

Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Yegappan Lakshmanan <yegappan@yahoo.com>

diff --git a/src/channel.c b/src/channel.c
index 1de376884a303a8f78acf7707dae1086f00ad44f..38f610a9fbcbf3aa4da1cafe2a0954c563ede4c3 100644 (file)
--- a/src/channel.c
+++ b/src/channel.c
@@ -3052,13 +3052,27 @@ may_invoke_callback(channel_T *channel, ch_part_T part)
     {
        // JSON or JS or LSP mode: invoke the one-time callback with the
        // matching nr
-       for (cbitem = cbhead->cq_next; cbitem != NULL; cbitem = cbitem->cq_next)
-           if (cbitem->cq_seq_nr == seq_nr)
+       int lsp_req_msg = FALSE;
+
+       // Don't use a LSP server request message with the same sequence number
+       // as the client request message as the response message.
+       if (ch_mode == CH_MODE_LSP && argv[1].v_type == VAR_DICT
+               && dict_has_key(argv[1].vval.v_dict, "method"))
+           lsp_req_msg = TRUE;
+
+       if (!lsp_req_msg)
+       {
+           for (cbitem = cbhead->cq_next; cbitem != NULL;
+                   cbitem = cbitem->cq_next)
            {
-               invoke_one_time_callback(channel, cbhead, cbitem, argv);
-               called_otc = TRUE;
-               break;
+               if (cbitem->cq_seq_nr == seq_nr)
+               {
+                   invoke_one_time_callback(channel, cbhead, cbitem, argv);
+                   called_otc = TRUE;
+                   break;
+               }
            }
+       }
     }
 
     if (seq_nr > 0 && (ch_mode != CH_MODE_LSP || called_otc))

diff --git a/src/testdir/test_channel.vim b/src/testdir/test_channel.vim
index edfd56e0bacc9697e45215b603c36c9a2f70f857..8f1291c22cacc23257591e05fa6b7cc18663c8b3 100644 (file)
--- a/src/testdir/test_channel.vim
+++ b/src/testdir/test_channel.vim
@@ -2478,23 +2478,32 @@ func Test_job_start_with_invalid_argument()
   call assert_fails('call job_start([0zff])', 'E976:')
 endfunc
 
-" Test for the 'lsp' channel mode
+" Process requests received from the LSP server
+func LspProcessServerRequests(chan, msg)
+  if a:msg['method'] == 'server-req-in-middle'
+        \ && a:msg['params']['text'] == 'server-req'
+    call ch_sendexpr(a:chan, #{method: 'server-req-in-middle-resp',
+          \ id: a:msg['id'], params: #{text: 'client-resp'}})
+  endif
+endfunc
+
+" LSP channel message callback function
 func LspCb(chan, msg)
   call add(g:lspNotif, a:msg)
   if a:msg->has_key('method')
-    " Requests received from the LSP server
-    if a:msg['method'] == 'server-req-in-middle'
-          \ && a:msg['params']['text'] == 'server-req'
-      call ch_sendexpr(a:chan, #{method: 'server-req-in-middle-resp',
-            \ id: a:msg['id'], params: #{text: 'client-resp'}})
-    endif
+    call LspProcessServerRequests(a:chan, a:msg)
   endif
 endfunc
 
+" LSP one-time message callback function (used for ch_sendexpr())
 func LspOtCb(chan, msg)
   call add(g:lspOtMsgs, a:msg)
+  if a:msg->has_key('method')
+    call LspProcessServerRequests(a:chan, a:msg)
+  endif
 endfunc
 
+" Test for the 'lsp' channel mode
 func LspTests(port)
   " call ch_logfile('Xlspclient.log', 'w')
   let ch = ch_open(s:localhost .. a:port, #{mode: 'lsp', callback: 'LspCb'})
@@ -2661,7 +2670,7 @@ func LspTests(port)
   call assert_equal('alive', ch_evalexpr(ch, #{method: 'ping'}).result)
 
   " Test for processing a request message from the server while the client
-  " is waiting for a response with the same identifier.
+  " is waiting for a response with the same identifier (sync-rpc)
   let g:lspNotif = []
   let resp = ch_evalexpr(ch, #{method: 'server-req-in-middle',
         \ params: #{text: 'client-req'}})
@@ -2673,6 +2682,44 @@ func LspTests(port)
         \ #{id: 28, jsonrpc: '2.0', method: 'server-req-in-middle',
         \   params: #{text: 'server-req'}}], g:lspNotif)
 
+  " Test for processing a request message from the server while the client
+  " is waiting for a response with the same identifier (async-rpc using the
+  " channel callback function)
+  let g:lspNotif = []
+  call ch_sendexpr(ch, #{method: 'server-req-in-middle', id: 500,
+        \ params: #{text: 'client-req'}})
+  " Send three pings to wait for all the notification messages to arrive
+  for i in range(3)
+    call assert_equal('alive', ch_evalexpr(ch, #{method: 'ping'}).result)
+  endfor
+  call assert_equal([
+        \ #{id: -1, jsonrpc: '2.0', method: 'server-req-in-middle',
+        \   params: #{text: 'server-notif'}},
+        \ #{id: 500, jsonrpc: '2.0', method: 'server-req-in-middle',
+        \   params: #{text: 'server-req'}},
+        \ #{id: 500, jsonrpc: '2.0', result: #{text: 'server-resp'}}
+        \ ], g:lspNotif)
+
+  " Test for processing a request message from the server while the client
+  " is waiting for a response with the same identifier (async-rpc using a
+  " one-time callback function)
+  let g:lspNotif = []
+  let g:lspOtMsgs = []
+  call ch_sendexpr(ch, #{method: 'server-req-in-middle',
+        \ params: #{text: 'client-req'}}, #{callback: 'LspOtCb'})
+  " Send a ping to wait for all the notification messages to arrive
+  for i in range(3)
+    call assert_equal('alive', ch_evalexpr(ch, #{method: 'ping'}).result)
+  endfor
+  call assert_equal([
+        \ #{id: 32, jsonrpc: '2.0', result: #{text: 'server-resp'}}],
+        \ g:lspOtMsgs)
+  call assert_equal([
+        \ #{id: -1, jsonrpc: '2.0', method: 'server-req-in-middle',
+        \ params: #{text: 'server-notif'}},
+        \ #{id: 32, jsonrpc: '2.0', method: 'server-req-in-middle',
+        \ params: {'text': 'server-req'}}], g:lspNotif)
+
   " Test for invoking an unsupported method
   let resp = ch_evalexpr(ch, #{method: 'xyz', params: {}}, #{timeout: 200})
   call assert_equal({}, resp)

diff --git a/src/version.c b/src/version.c
index 16e3e8a359301f022b012097ec94a7588e34c5ad..417bbc15d8d06dc5bccf971670e9f16ed7524ffd 100644 (file)
--- a/src/version.c
+++ b/src/version.c
@@ -699,6 +699,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1939,
 /**/
     1938,
 /**/