fix: Tab passthrough

Fixes #670

Author: AntoineGS

lua/copilot/keymaps/init.lua

@@ -59,7 +59,7 @@ local function save_existing_keymap(mode, key, keymap_key)
       logger.trace("Saved existing keymap for " .. keymap_key .. ": " .. existing.rhs)
       return
     elseif existing.callback then
-      previous_keymaps[keymap_key] = { type = "callback", value = existing.callback }
+      previous_keymaps[keymap_key] = { type = "callback", value = existing.callback, expr = existing.expr == 1 }
       logger.trace("Saved existing keymap callback for " .. keymap_key)
       return
     end
@@ -110,13 +110,16 @@ function M.register_keymap_with_passthrough(mode, key, action, desc, bufnr)
         return "<Ignore>"
       elseif prev.type == "callback" then
         logger.trace("Passing through to previous keymap callback for " .. keymap_key)
+        if prev.expr then
+          return prev.value()
+        end
         prev.value()
         return "<Ignore>"
       end
     end
 
     logger.trace("No previous keymap to pass through for " .. keymap_key)
-    return key
+    return vim.api.nvim_replace_termcodes(key, true, false, true)
   end, {
     desc = desc,
     expr = true,

tests/test_keymaps.lua

@@ -76,4 +76,16 @@ T["keymaps()"]["passthrough Esc - return true, will not remove hl"] = function()
   reference_screenshot(child.get_screenshot(), nil, { ignore_text = { 9, 10 }, ignore_attr = { 9, 10 } })
 end
 
+T["keymaps()"]["passthrough Tab - return false inserts tab character"] = function()
+  child.lua([[
+    require("copilot.keymaps").register_keymap_with_passthrough("i", "<Tab>", function()
+      return false
+    end, "Passthrough Tab", vim.api.nvim_get_current_buf())
+  ]])
+  child.type_keys("i", "hello", "<Tab>", "world", "<Esc>")
+
+  local line = child.lua("return vim.api.nvim_get_current_line()")
+  MiniTest.expect.equality(line, "hello\tworld")
+end
+
 return T