mode: enter/exit debug mode with keybinding lifecycle

tests/test_keys.lua

@@ -0,0 +1,28 @@
+-- tests for keybinding stash/restore
+local td = require("tiny-debugger")
+
+local function assert_eq(a, b, msg)
+  if a ~= b then
+    error(string.format("FAIL: %s — expected %s, got %s", msg, vim.inspect(b), vim.inspect(a)))
+  end
+end
+
+-- set a custom mapping for 'c'
+local custom_called = false
+vim.keymap.set("n", "c", function() custom_called = true end, { buffer = 0, desc = "custom c" })
+
+-- verify custom mapping exists
+local maparg = vim.fn.maparg("c", "n", false, true)
+assert_eq(maparg.desc, "custom c", "custom mapping exists before enter")
+
+-- enter debug mode — should override 'c'
+td.toggle()
+maparg = vim.fn.maparg("c", "n", false, true)
+assert_eq(maparg.desc, "tiny-debugger: continue", "c overridden in debug mode")
+
+-- exit debug mode — should restore custom 'c'
+td.toggle()
+maparg = vim.fn.maparg("c", "n", false, true)
+assert_eq(maparg.desc, "custom c", "custom mapping restored after exit")
+
+print("ALL KEY STASH/RESTORE TESTS PASSED")