handle split resize safely + use store subscribe (#328)

* fix(ui): handle split resize safely

Use window-type-aware resize logic in output_window.update_dimensions.
- guard missing or invalid output_win before resizing
- use nvim_win_set_width for split windows (relative == '')
- keep nvim_win_set_config for floating windows
- add regression tests for float-focus resize and invalid window

This prevents "Cannot split a floating window" on VimResized while
preserving existing zoom width behavior.

Verified with:
- ./run_tests.sh -t tests/unit/zoom_spec.lua

* fix(reference-picker): use store subscribe

Follow the state observable API migration by switching reference picker setup from state.subscribe(...) to state.store.subscribe(...).

This matches the refactor that centralized observable helpers under state.store and fixes startup error: attempt to call field 'subscribe' (a nil value).

Verified with: ./run_tests.sh -t tests/unit/reference_picker_spec.lua

---------

Co-authored-by: oujinsai <[email protected]>

Author: jensenojs

lua/opencode/ui/output_window.lua

@@ -132,6 +132,11 @@ function M.update_dimensions(windows)
   if config.ui.position == 'current' then
     return
   end
+
+  if not windows or not windows.output_win or not vim.api.nvim_win_is_valid(windows.output_win) then
+    return
+  end
+
   local total_width = vim.api.nvim_get_option_value('columns', {})
 
   local width_ratio
@@ -145,8 +150,17 @@ function M.update_dimensions(windows)
   end
 
   local width = math.floor(total_width * width_ratio)
+  local ok, win_config = pcall(vim.api.nvim_win_get_config, windows.output_win)
+  if not ok then
+    return
+  end
+
+  if win_config.relative == '' then
+    pcall(vim.api.nvim_win_set_width, windows.output_win, width)
+    return
+  end
 
-  vim.api.nvim_win_set_config(windows.output_win, { width = width })
+  pcall(vim.api.nvim_win_set_config, windows.output_win, { width = width })
 end
 
 function M.get_buf_line_count()

tests/unit/zoom_spec.lua

@@ -228,6 +228,68 @@ describe('ui zoom state', function()
 
       assert.equals(80, state.pre_zoom_width)
     end)
+
+    it('does not error when focused window is floating and output window is split', function()
+      local split_buf = vim.api.nvim_create_buf(false, true)
+      local focus_buf = vim.api.nvim_create_buf(false, true)
+      local split_win
+      local focus_win
+
+      local normal_win
+      for _, win in ipairs(vim.api.nvim_list_wins()) do
+        if vim.api.nvim_win_is_valid(win) and vim.api.nvim_win_get_config(win).relative == '' then
+          normal_win = win
+          break
+        end
+      end
+
+      assert.is_not_nil(normal_win)
+      vim.api.nvim_set_current_win(normal_win)
+      vim.cmd('vsplit')
+      split_win = vim.api.nvim_get_current_win()
+      vim.api.nvim_win_set_buf(split_win, split_buf)
+
+      focus_win = vim.api.nvim_open_win(focus_buf, true, {
+        relative = 'editor',
+        width = 20,
+        height = 5,
+        row = 1,
+        col = 1,
+        style = 'minimal',
+      })
+
+      assert.has_no.errors(function()
+        output_window.update_dimensions({ output_win = split_win, output_buf = split_buf })
+      end)
+
+      local expected_width = math.floor(config.ui.window_width * vim.o.columns)
+      assert.equals(expected_width, vim.api.nvim_win_get_width(split_win))
+
+      pcall(vim.api.nvim_win_close, focus_win, true)
+      pcall(vim.api.nvim_win_close, split_win, true)
+      pcall(vim.api.nvim_buf_delete, focus_buf, { force = true })
+      pcall(vim.api.nvim_buf_delete, split_buf, { force = true })
+    end)
+
+    it('does not error when output window is invalid', function()
+      local invalid_buf = vim.api.nvim_create_buf(false, true)
+      local invalid_win = vim.api.nvim_open_win(invalid_buf, false, {
+        relative = 'editor',
+        width = 20,
+        height = 5,
+        row = 2,
+        col = 2,
+        style = 'minimal',
+      })
+
+      vim.api.nvim_win_close(invalid_win, true)
+
+      assert.has_no.errors(function()
+        output_window.update_dimensions({ output_win = invalid_win, output_buf = invalid_buf })
+      end)
+
+      pcall(vim.api.nvim_buf_delete, invalid_buf, { force = true })
+    end)
   end)
 
   describe('zoom state persistence', function()