vim-patch:8.2.0812: mapset() does not properly handle <> notation

Problem:    mapset() does not properly handle <> notation.
Solution:   Convert <> codes. (closes vim/vim#6116)
https://github.com/vim/vim/commit/c94c1467b9b86156a6b7c8d3e41ff01c13d2be07

2 files changed, 73 insertions, 3 deletions

diff --git a/src/nvim/mapping.c b/src/nvim/mapping.c
index 384497174d..3613849a73 100644
--- a/src/nvim/mapping.c
+++ b/src/nvim/mapping.c
@@ -2150,6 +2150,9 @@ void f_mapset(typval_T *argvars, typval_T *rettv, FunPtr fptr)
     emsg(_("E99: rhs entry missing in mapset() dict argument"));
     return;
   }
+  char *orig_rhs = rhs;
+  char *arg_buf = NULL;
+  rhs = replace_termcodes(rhs, STRLEN(rhs), &arg_buf, REPTERM_DO_LT, NULL, CPO_TO_CPO_FLAGS);
 
   int noremap = tv_dict_get_number(d, "noremap") ? REMAP_NONE : 0;
   if (tv_dict_get_number(d, "script") != 0) {
@@ -2158,9 +2161,9 @@ void f_mapset(typval_T *argvars, typval_T *rettv, FunPtr fptr)
 
   // TODO: support "callback" and "desc"
   MapArguments args = {
-    .rhs = vim_strsave((char_u *)rhs),
+    .rhs = (char_u *)rhs,
     .rhs_lua = LUA_NOREF,
-    .orig_rhs = vim_strsave((char_u *)rhs),
+    .orig_rhs = vim_strsave((char_u *)orig_rhs),
     .expr = tv_dict_get_number(d, "expr") != 0,
     .silent = tv_dict_get_number(d, "silent") != 0,
     .nowait = tv_dict_get_number(d, "nowait") != 0,
diff --git a/src/nvim/testdir/test_maparg.vim b/src/nvim/testdir/test_maparg.vim
index ec9af3d825..6fea66b7c6 100644
--- a/src/nvim/testdir/test_maparg.vim
+++ b/src/nvim/testdir/test_maparg.vim
@@ -6,7 +6,7 @@ func s:SID()
   return str2nr(matchstr(expand('<sfile>'), '<SNR>\zs\d\+\ze_SID$'))
 endfunc
 
-funct Test_maparg()
+func Test_maparg()
   new
   set cpo-=<
   set encoding=utf8
@@ -170,6 +170,73 @@ endfunc
 func Test_mapset()
   call One_mapset_test('K')
   call One_mapset_test('<F3>')
+
+  " Check <> key conversion
+  new
+  inoremap K one<Left>x
+  call feedkeys("iK\<Esc>", 'xt')
+  call assert_equal('onxe', getline(1))
+
+  let orig = maparg('K', 'i', 0, 1)
+  call assert_equal('K', orig.lhs)
+  call assert_equal('one<Left>x', orig.rhs)
+  call assert_equal('i', orig.mode)
+
+  iunmap K
+  let d = maparg('K', 'i', 0, 1)
+  call assert_equal({}, d)
+
+  call mapset('i', 0, orig)
+  call feedkeys("SK\<Esc>", 'xt')
+  call assert_equal('onxe', getline(1))
+
+  iunmap K
+
+  " Test literal <CR> using a backslash
+  let cpo_save = &cpo
+  set cpo-=B
+  inoremap K one\<CR>two
+  call feedkeys("SK\<Esc>", 'xt')
+  call assert_equal('one<CR>two', getline(1))
+
+  let orig = maparg('K', 'i', 0, 1)
+  call assert_equal('K', orig.lhs)
+  call assert_equal('one\<CR>two', orig.rhs)
+  call assert_equal('i', orig.mode)
+
+  iunmap K
+  let d = maparg('K', 'i', 0, 1)
+  call assert_equal({}, d)
+
+  call mapset('i', 0, orig)
+  call feedkeys("SK\<Esc>", 'xt')
+  call assert_equal('one<CR>two', getline(1))
+
+  iunmap K
+  let &cpo = cpo_save
+
+  " Test literal <CR> using CTRL-V
+  inoremap K one<CR>two
+  call feedkeys("SK\<Esc>", 'xt')
+  call assert_equal('one<CR>two', getline(1))
+
+  let orig = maparg('K', 'i', 0, 1)
+  call assert_equal('K', orig.lhs)
+  call assert_equal("one\x16<CR>two", orig.rhs)
+  call assert_equal('i', orig.mode)
+
+  iunmap K
+  let d = maparg('K', 'i', 0, 1)
+  call assert_equal({}, d)
+
+  call mapset('i', 0, orig)
+  call feedkeys("SK\<Esc>", 'xt')
+  call assert_equal('one<CR>two', getline(1))
+
+  iunmap K
+  let &cpo = cpo_save
+
+  bwipe!
 endfunc
 
 " vim: shiftwidth=2 sts=2 expandtab