From 3601cef1377937f01347b20a8c6c303f5f429f51 Mon Sep 17 00:00:00 2001
From: zeertzjq <zeertzjq@outlook.com>
Date: Wed, 27 Apr 2022 21:27:58 +0800
Subject: [PATCH] feat(mappings): do not replace existing mapping for
 simplified form

---
 runtime/doc/vim_diff.txt          |  4 +++
 src/nvim/getchar.c                |  5 +++
 test/functional/ui/input_spec.lua | 57 +++++++++++++++++++++++--------
 3 files changed, 51 insertions(+), 15 deletions(-)

diff --git a/runtime/doc/vim_diff.txt b/runtime/doc/vim_diff.txt
index 540043f52d..bada506c63 100644
--- a/runtime/doc/vim_diff.txt
+++ b/runtime/doc/vim_diff.txt
@@ -365,6 +365,10 @@ Macro/|recording| behavior
   macros and 'keymap' at the same time. This also means you can use |:imap| on
   the results of keys from 'keymap'.
 
+Mappings:
+  Creating a mapping for a simplifiable key (e.g. <C-I>) doesn't replace an
+  existing mapping for its simplified form (e.g. <Tab>).
+
 Motion:
   The |jumplist| avoids useless/phantom jumps.
 
diff --git a/src/nvim/getchar.c b/src/nvim/getchar.c
index a26ca3f2c8..58daa9631a 100644
--- a/src/nvim/getchar.c
+++ b/src/nvim/getchar.c
@@ -3279,6 +3279,11 @@ int buf_do_map(int maptype, MapArguments *args, int mode, bool is_abbrev, buf_T
               } else if (n != len) {  // new entry is ambiguous
                 mpp = &(mp->m_next);
                 continue;
+              } else if (keyround1_simplified && !mp->m_simplified) {
+                // In keyround for simplified keys, don't replace
+                // a mapping without m_simplified flag.
+                did_it = true;
+                break;
               } else if (args->unique) {
                 if (is_abbrev) {
                   semsg(_("E226: abbreviation already exists for %s"), p);
diff --git a/test/functional/ui/input_spec.lua b/test/functional/ui/input_spec.lua
index 25fc9cdcd1..0f4e97088c 100644
--- a/test/functional/ui/input_spec.lua
+++ b/test/functional/ui/input_spec.lua
@@ -173,11 +173,20 @@ describe('input pairs', function()
       eq('\t\t', curbuf_contents())
     end)
 
-    it('can be mapped', function()
-      command('inoremap <tab> TAB!')
-      command('inoremap <c-i> CTRL-I!')
-      feed('i<tab><c-i><esc>')
-      eq('TAB!CTRL-I!', curbuf_contents())
+    describe('can be mapped separately', function()
+      it('if <tab> is mapped after <c-i>', function()
+        command('inoremap <c-i> CTRL-I!')
+        command('inoremap <tab> TAB!')
+        feed('i<tab><c-i><esc>')
+        eq('TAB!CTRL-I!', curbuf_contents())
+      end)
+
+      it('if <tab> is mapped before <c-i>', function()
+        command('inoremap <tab> TAB!')
+        command('inoremap <c-i> CTRL-I!')
+        feed('i<tab><c-i><esc>')
+        eq('TAB!CTRL-I!', curbuf_contents())
+      end)
     end)
   end)
 
@@ -187,11 +196,20 @@ describe('input pairs', function()
       eq('unos\ndos\ntres', curbuf_contents())
     end)
 
-    it('can be mapped', function()
-      command('inoremap <c-m> SNIPPET!')
-      command('inoremap <cr> , and then<cr>')
-      feed('iunos<c-m>dos<cr>tres<esc>')
-      eq('unosSNIPPET!dos, and then\ntres', curbuf_contents())
+    describe('can be mapped separately', function()
+      it('if <cr> is mapped after <c-m>', function()
+        command('inoremap <c-m> SNIPPET!')
+        command('inoremap <cr> , and then<cr>')
+        feed('iunos<c-m>dos<cr>tres<esc>')
+        eq('unosSNIPPET!dos, and then\ntres', curbuf_contents())
+      end)
+
+      it('if <cr> is mapped before <c-m>', function()
+        command('inoremap <cr> , and then<cr>')
+        command('inoremap <c-m> SNIPPET!')
+        feed('iunos<c-m>dos<cr>tres<esc>')
+        eq('unosSNIPPET!dos, and then\ntres', curbuf_contents())
+      end)
     end)
   end)
 
@@ -201,11 +219,20 @@ describe('input pairs', function()
       eq('doubledoublesingle', curbuf_contents())
     end)
 
-    it('can be mapped', function()
-      command('inoremap <c-[> HALLOJ!')
-      command('inoremap <esc> ,<esc>')
-      feed('2adubbel<c-[>upp<esc>')
-      eq('dubbelHALLOJ!upp,dubbelHALLOJ!upp,', curbuf_contents())
+    describe('can be mapped separately', function()
+      it('if <esc> is mapped after <c-[>', function()
+        command('inoremap <c-[> HALLOJ!')
+        command('inoremap <esc> ,<esc>')
+        feed('2adubbel<c-[>upp<esc>')
+        eq('dubbelHALLOJ!upp,dubbelHALLOJ!upp,', curbuf_contents())
+      end)
+
+      it('if <esc> is mapped before <c-[>', function()
+        command('inoremap <esc> ,<esc>')
+        command('inoremap <c-[> HALLOJ!')
+        feed('2adubbel<c-[>upp<esc>')
+        eq('dubbelHALLOJ!upp,dubbelHALLOJ!upp,', curbuf_contents())
+      end)
     end)
   end)
 end)