From c9ccbe56179f1d4adb06fea47f4eea0c57736c2d Mon Sep 17 00:00:00 2001
From: Folke Lemaitre <folke.lemaitre@gmail.com>
Date: Fri, 24 Oct 2025 07:20:23 +0200
Subject: [PATCH] fix(picker): fix race condition causing "Finder yielded after
 done" error. Closes #2327
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The old code had a race condition where:
1. R:request() scheduled LSP request setup but immediately suspended
2. R:wait() checked #self.requests (still 0) and returned immediately
3. Finder completed and set running = false
4. Then scheduled function ran and LSP responses came back
5. Callbacks tried to yield items but finder was already done → error

The fix uses a pending counter to track when the scheduled setup function
is running, ensuring we wait for both the setup to complete AND all LSP
responses before the finder completes.

Also improved error handling by checking the err parameter in callbacks.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>
---
 lua/snacks/picker/source/lsp/init.lua | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/lua/snacks/picker/source/lsp/init.lua b/lua/snacks/picker/source/lsp/init.lua
index c7bd05dc..d9f02648 100644
--- a/lua/snacks/picker/source/lsp/init.lua
+++ b/lua/snacks/picker/source/lsp/init.lua
@@ -6,6 +6,7 @@ local Async = require("snacks.picker.util.async")
 local M = {}
 
 ---@alias lsp.Symbol lsp.SymbolInformation|lsp.DocumentSymbol
+---@alias lsp.Loc lsp.LocationLink|lsp.Location
 
 ---@class snacks.picker.lsp.Loc: lsp.Location
 ---@field encoding string
@@ -99,6 +100,7 @@ end
 ---@field async snacks.picker.Async
 ---@field requests {client_id:number, request_id:number}[]
 ---@field completed number
+---@field pending integer
 local R = {}
 R.__index = R
 
@@ -106,6 +108,7 @@ function R.new()
   local self = setmetatable({}, R)
   self.async = Async.running()
   self.requests = {}
+  self.pending = 0
   self.completed = 0
   self.async:on(
     "abort",
@@ -132,6 +135,7 @@ end
 ---@param cb fun(client:vim.lsp.Client, result:table, params:table)
 ---@async
 function R:request(buf, method, params, cb)
+  self.pending = self.pending + 1
   vim.schedule(function()
     local clients = type(buf) == "number" and M.get_clients(buf, method)
       or {
@@ -139,11 +143,8 @@ function R:request(buf, method, params, cb)
       }
     for _, client in ipairs(clients) do
       local p = params(client)
-      local status, request_id = client:request(method, p, function(_, result)
-        if self.async._aborted then
-          return
-        end
-        if result then
+      local status, request_id = client:request(method, p, function(err, result)
+        if not err and result and not self.async._aborted then
           cb(client, result, p)
         end
         self.completed = self.completed + 1
@@ -153,14 +154,14 @@ function R:request(buf, method, params, cb)
         table.insert(self.requests, { client_id = client.id, request_id = request_id })
       end
     end
+    self.pending = self.pending - 1
     self.async:resume()
   end)
-  self.async:suspend()
   return self
 end
 
 function R:wait()
-  while self.completed < #self.requests do
+  while self.pending > 0 or self.completed < #self.requests do
     self.async:suspend()
   end
 end