fix(diff): keep terminal focus for floating terminals (#178)

Author: ThomasK33

README.md

@@ -280,7 +280,7 @@ For deep technical details, see [ARCHITECTURE.md](./ARCHITECTURE.md).
       auto_close_on_accept = true,
       vertical_split = true,
       open_in_current_tab = true,
-      keep_terminal_focus = false, -- If true, moves focus back to terminal after diff opens
+      keep_terminal_focus = false, -- If true, moves focus back to terminal after diff opens (including floating terminals)
     },
   },
   keys = {

lua/claudecode/config.lua

@@ -23,7 +23,7 @@ M.defaults = {
   diff_opts = {
     layout = "vertical",
     open_in_new_tab = false, -- Open diff in a new tab (false = use current tab)
-    keep_terminal_focus = false, -- If true, moves focus back to terminal after diff opens
+    keep_terminal_focus = false, -- If true, moves focus back to terminal after diff opens (including floating terminals)
     hide_terminal_in_new_tab = false, -- If true and opening in a new tab, do not show Claude terminal there
     on_new_file_reject = "keep_empty", -- "keep_empty" leaves an empty buffer; "close_window" closes the placeholder split
   },

lua/claudecode/diff.lua

@@ -101,17 +101,24 @@ local function find_claudecode_terminal_window()
     return nil
   end
 
-  -- Find the window containing this buffer
+  -- Find the window containing this buffer.
+  -- Prefer a normal split window, but fall back to a floating terminal window (e.g. Snacks position="float").
+  local floating_fallback = nil
+
   for _, win in ipairs(vim.api.nvim_list_wins()) do
     if vim.api.nvim_win_get_buf(win) == terminal_bufnr then
       local win_config = vim.api.nvim_win_get_config(win)
-      if not (win_config.relative and win_config.relative ~= "") then
+      local is_floating = win_config.relative and win_config.relative ~= ""
+
+      if is_floating then
+        floating_fallback = floating_fallback or win
+      else
         return win
       end
     end
   end
 
-  return nil
+  return floating_fallback
 end
 
 ---Create a split based on configured layout
@@ -619,11 +626,17 @@ local function setup_new_buffer(
         term_tab = vim.api.nvim_win_get_tabpage(terminal_win)
       end)
       if term_tab == current_tab then
-        local terminal_config = config.terminal or {}
-        local split_width = terminal_config.split_width_percentage or 0.30
-        local total_width = vim.o.columns
-        local terminal_width = math.floor(total_width * split_width)
-        pcall(vim.api.nvim_win_set_width, terminal_win, terminal_width)
+        local win_config = vim.api.nvim_win_get_config(terminal_win)
+        local is_floating = win_config.relative and win_config.relative ~= ""
+
+        -- Only resize split terminals. Floating terminals control their own sizing.
+        if not is_floating then
+          local terminal_config = config.terminal or {}
+          local split_width = terminal_config.split_width_percentage or 0.30
+          local total_width = vim.o.columns
+          local terminal_width = math.floor(total_width * split_width)
+          pcall(vim.api.nvim_win_set_width, terminal_win, terminal_width)
+        end
       end
     end
   end
@@ -1015,14 +1028,20 @@ function M._cleanup_diff_state(tab_name, reason)
     local terminal_ok, terminal_module = pcall(require, "claudecode.terminal")
     if terminal_ok and diff_data.had_terminal_in_original then
       pcall(terminal_module.ensure_visible)
-      -- And restore its configured width if it is visible
+      -- And restore its configured width if it is visible.
+      -- (We intentionally do not resize floating terminals.)
       local terminal_win = find_claudecode_terminal_window()
       if terminal_win and vim.api.nvim_win_is_valid(terminal_win) then
-        local terminal_config = config.terminal or {}
-        local split_width = terminal_config.split_width_percentage or 0.30
-        local total_width = vim.o.columns
-        local terminal_width = math.floor(total_width * split_width)
-        pcall(vim.api.nvim_win_set_width, terminal_win, terminal_width)
+        local win_config = vim.api.nvim_win_get_config(terminal_win)
+        local is_floating = win_config.relative and win_config.relative ~= ""
+
+        if not is_floating then
+          local terminal_config = config.terminal or {}
+          local split_width = terminal_config.split_width_percentage or 0.30
+          local total_width = vim.o.columns
+          local terminal_width = math.floor(total_width * split_width)
+          pcall(vim.api.nvim_win_set_width, terminal_win, terminal_width)
+        end
       end
     end
   else
@@ -1038,14 +1057,20 @@ function M._cleanup_diff_state(tab_name, reason)
       end)
     end
 
-    -- After closing the diff in the same tab, restore terminal width if visible
+    -- After closing the diff in the same tab, restore terminal width if visible.
+    -- (We intentionally do not resize floating terminals.)
     local terminal_win = find_claudecode_terminal_window()
     if terminal_win and vim.api.nvim_win_is_valid(terminal_win) then
-      local terminal_config = config.terminal or {}
-      local split_width = terminal_config.split_width_percentage or 0.30
-      local total_width = vim.o.columns
-      local terminal_width = math.floor(total_width * split_width)
-      pcall(vim.api.nvim_win_set_width, terminal_win, terminal_width)
+      local win_config = vim.api.nvim_win_get_config(terminal_win)
+      local is_floating = win_config.relative and win_config.relative ~= ""
+
+      if not is_floating then
+        local terminal_config = config.terminal or {}
+        local split_width = terminal_config.split_width_percentage or 0.30
+        local total_width = vim.o.columns
+        local terminal_width = math.floor(total_width * split_width)
+        pcall(vim.api.nvim_win_set_width, terminal_win, terminal_width)
+      end
     end
   end
 

tests/unit/diff_keep_terminal_focus_float_spec.lua

@@ -0,0 +1,112 @@
+require("tests.busted_setup")
+
+-- Regression test for #150:
+-- When diff_opts.keep_terminal_focus = true and the Claude terminal lives in a floating window,
+-- opening a diff should return focus to the floating terminal (not the diff split behind it).
+
+describe("Diff keep_terminal_focus with floating terminal", function()
+  local diff
+
+  local test_old_file = "/tmp/claudecode_keep_focus_old.txt"
+  local test_new_file = "/tmp/claudecode_keep_focus_new.txt"
+  local tab_name = "keep-focus-float"
+
+  local editor_win = 1000
+  local terminal_win = 1001
+  local terminal_buf
+
+  before_each(function()
+    -- Fresh vim mock state
+    if vim and vim._mock and vim._mock.reset then
+      vim._mock.reset()
+    end
+
+    -- Ensure predictable tab/window state
+    vim._tabs = { [1] = true }
+    vim._current_tabpage = 1
+
+    -- Reload diff module cleanly
+    package.loaded["claudecode.diff"] = nil
+    diff = require("claudecode.diff")
+
+    -- Create a normal, non-floating editor window
+    local editor_buf = vim.api.nvim_create_buf(true, false)
+    vim._windows[editor_win] = { buf = editor_buf, width = 80 }
+    vim._win_tab[editor_win] = 1
+
+    -- Create a floating window for the terminal
+    terminal_buf = vim.api.nvim_create_buf(false, true)
+    vim.api.nvim_buf_set_option(terminal_buf, "buftype", "terminal")
+    vim._windows[terminal_win] = {
+      buf = terminal_buf,
+      width = 80,
+      config = { relative = "editor" },
+    }
+    vim._win_tab[terminal_win] = 1
+
+    vim._tab_windows[1] = { editor_win, terminal_win }
+    vim._current_window = terminal_win
+    vim._next_winid = 1002
+
+    -- Provide minimal config directly to diff module
+    diff.setup({
+      terminal = { split_side = "right", split_width_percentage = 0.30 },
+      diff_opts = {
+        layout = "vertical",
+        open_in_new_tab = false,
+        keep_terminal_focus = true,
+      },
+    })
+
+    -- Stub terminal provider with a valid terminal buffer
+    package.loaded["claudecode.terminal"] = {
+      get_active_terminal_bufnr = function()
+        return terminal_buf
+      end,
+      ensure_visible = function() end,
+    }
+
+    -- Create a real file so filereadable() returns 1 in mocks
+    local f = io.open(test_old_file, "w")
+    f:write("line1\nline2\n")
+    f:close()
+
+    -- Ensure a clean diff state
+    diff._cleanup_all_active_diffs("test_setup")
+  end)
+
+  after_each(function()
+    os.remove(test_old_file)
+    os.remove(test_new_file)
+
+    package.loaded["claudecode.terminal"] = nil
+
+    if diff then
+      diff._cleanup_all_active_diffs("test_teardown")
+    end
+  end)
+
+  it("restores focus to floating terminal window after diff opens", function()
+    local co = coroutine.create(function()
+      diff.open_diff_blocking(test_old_file, test_new_file, "updated content\n", tab_name)
+    end)
+
+    local ok, err = coroutine.resume(co)
+    assert.is_true(ok, tostring(err))
+    assert.equal("suspended", coroutine.status(co))
+
+    -- keep_terminal_focus uses vim.schedule; the vim mock executes scheduled callbacks immediately.
+
+    -- Floating terminals (e.g. Snacks) should manage their own sizing.
+    assert.equal(80, vim.api.nvim_win_get_width(terminal_win))
+    assert.equal(terminal_win, vim.api.nvim_get_current_win())
+
+    -- Resolve to finish the coroutine
+    vim.schedule(function()
+      diff._resolve_diff_as_rejected(tab_name)
+    end)
+    vim.wait(100, function()
+      return coroutine.status(co) == "dead"
+    end)
+  end)
+end)