edit.c: CTRL-SPC: Insert previously-inserted text. #6090

Default Vim behavior of i_CTRL-<Space> is to insert the last-inserted
text and exit insert mode. :help i_CTRL-@

Before this commit that did not happen because insert_handle_key()
checks for NUL instead of checking for ' ' with a CTRL `mod_mask`.

I'm leaving the check for NUL despite the fact that at the moment that
key is never seen when using the terminal UI (not for C-Space, nor C-@).
This is because I assume it's still allowed for other front-ends to pass
NUL, but at the moment the terminal UI isn't.

1 files changed, 22 insertions, 0 deletions

diff --git a/test/functional/insert/last_inserted_spec.lua b/test/functional/insert/last_inserted_spec.lua
new file mode 100644
index 0000000000..dce23a3790
--- /dev/null
+++ b/test/functional/insert/last_inserted_spec.lua
@@ -0,0 +1,22 @@
+local helpers = require('test.functional.helpers')(after_each)
+local clear, feed, insert = helpers.clear, helpers.feed, helpers.insert
+local expect = helpers.expect
+
+clear()
+
+describe('insert-mode', function()
+  it('CTRL-@ inserts last-inserted text, leaves insert-mode', function()
+    insert('hello')
+    feed('i<C-@>x')
+    expect('hellhello')
+  end)
+  -- C-Space is the same as C-@
+  it('CTRL-SPC inserts last-inserted text, leaves insert-mode', function()
+    feed('i<C-Space>x')
+    expect('hellhellhello')
+  end)
+  it('CTRL-A inserts last inserted text', function()
+    feed('i<C-A>x')
+    expect('hellhellhellhelloxo')
+  end)
+end)