fix(lsp): check if buffer was detached in on_init callback (#28914)

Co-authored-by: Jongwook Choi <wookayin@gmail.com>

3 files changed, 24 insertions, 25 deletions

diff --git a/test/functional/plugin/lsp/inlay_hint_spec.lua b/test/functional/plugin/lsp/inlay_hint_spec.lua
index 3d0fcc31ff..d3b5ae0e4e 100644
--- a/test/functional/plugin/lsp/inlay_hint_spec.lua
+++ b/test/functional/plugin/lsp/inlay_hint_spec.lua
@@ -70,8 +70,8 @@ before_each(function()
         inlayHintProvider = true,
       },
       handlers = {
-        ['textDocument/inlayHint'] = function()
-          return vim.json.decode(response)
+        ['textDocument/inlayHint'] = function(_, _, callback)
+          callback(nil, vim.json.decode(response))
         end,
       }
     })
@@ -106,8 +106,8 @@ describe('vim.lsp.inlay_hint', function()
           inlayHintProvider = true,
         },
         handlers = {
-          ['textDocument/inlayHint'] = function()
-            return {}
+          ['textDocument/inlayHint'] = function(_, _, callback)
+            callback(nil, {})
           end,
         }
       })
@@ -206,8 +206,8 @@ describe('vim.lsp.inlay_hint', function()
             inlayHintProvider = true,
           },
           handlers = {
-            ['textDocument/inlayHint'] = function()
-              return { expected2 }
+            ['textDocument/inlayHint'] = function(_, _, callback)
+              callback(nil, { expected2 })
             end,
           }
         })
diff --git a/test/functional/plugin/lsp/semantic_tokens_spec.lua b/test/functional/plugin/lsp/semantic_tokens_spec.lua
index 60f02b0521..7908c5d2e7 100644
--- a/test/functional/plugin/lsp/semantic_tokens_spec.lua
+++ b/test/functional/plugin/lsp/semantic_tokens_spec.lua
@@ -95,11 +95,11 @@ describe('semantic token highlighting', function()
             },
           },
           handlers = {
-            ['textDocument/semanticTokens/full'] = function()
-              return vim.fn.json_decode(response)
+            ['textDocument/semanticTokens/full'] = function(_, _, callback)
+              callback(nil, vim.fn.json_decode(response))
             end,
-            ['textDocument/semanticTokens/full/delta'] = function()
-              return vim.fn.json_decode(edit_response)
+            ['textDocument/semanticTokens/full/delta'] = function(_, _, callback)
+              callback(nil, vim.fn.json_decode(edit_response))
             end,
           }
         })
@@ -560,11 +560,11 @@ describe('semantic token highlighting', function()
             },
           },
           handlers = {
-            ['textDocument/semanticTokens/full'] = function()
-              return nil
+            ['textDocument/semanticTokens/full'] = function(_, _, callback)
+              callback(nil, nil)
             end,
             ['textDocument/semanticTokens/full/delta'] = function()
-              return nil
+              callback(nil, nil)
             end,
           }
         })
@@ -608,11 +608,11 @@ describe('semantic token highlighting', function()
             },
           },
           handlers = {
-            ['textDocument/semanticTokens/full'] = function()
-              return vim.fn.json_decode(response)
+            ['textDocument/semanticTokens/full'] = function(_, _, callback)
+              callback(nil, vim.fn.json_decode(response))
             end,
-            ['textDocument/semanticTokens/full/delta'] = function()
-              return vim.fn.json_decode(edit_response)
+            ['textDocument/semanticTokens/full/delta'] = function(_, _, callback)
+              callback(nil, vim.fn.json_decode(edit_response))
             end,
           }
         })
@@ -1075,8 +1075,8 @@ b = "as"]],
               },
             },
             handlers = {
-              ['textDocument/semanticTokens/full'] = function()
-                return vim.fn.json_decode(resp)
+              ['textDocument/semanticTokens/full'] = function(_, _, callback)
+                callback(nil, vim.fn.json_decode(resp))
               end,
             }
           })
@@ -1461,11 +1461,11 @@ int main()
               },
             },
             handlers = {
-              ['textDocument/semanticTokens/full'] = function()
-                return vim.fn.json_decode(resp1)
+              ['textDocument/semanticTokens/full'] = function(_, _, callback)
+                callback(nil, vim.fn.json_decode(resp1))
               end,
-              ['textDocument/semanticTokens/full/delta'] = function()
-                return vim.fn.json_decode(resp2)
+              ['textDocument/semanticTokens/full/delta'] = function(_, _, callback)
+                callback(nil, vim.fn.json_decode(resp2))
               end,
             }
           })
diff --git a/test/functional/plugin/lsp/testutil.lua b/test/functional/plugin/lsp/testutil.lua
index 4d14752f2a..3430a1e1a3 100644
--- a/test/functional/plugin/lsp/testutil.lua
+++ b/test/functional/plugin/lsp/testutil.lua
@@ -39,8 +39,7 @@ M.create_server_definition = [[
         })
         local handler = handlers[method]
         if handler then
-          local response, err = handler(method, params)
-          callback(err, response)
+          handler(method, params, callback)
         elseif method == 'initialize' then
           callback(nil, {
             capabilities = opts.capabilities or {}