test: port kword_test to Lua for utf_char2bytes()

Use LuaJIT FFI to create char pointer.
Validate output with utf_ptr2char(), vim_iswordc() and vim_iswordp().
Use const for LuaJIT string-to-char conversion.

2 files changed, 14 insertions, 4 deletions

diff --git a/src/nvim/charset.c b/src/nvim/charset.c
index d1d9de5487..ab20996df7 100644
--- a/src/nvim/charset.c
+++ b/src/nvim/charset.c
@@ -826,7 +826,7 @@ bool vim_isIDc(int c)
 /// For multi-byte characters mb_get_class() is used (builtin rules).
 ///
 /// @param  c  character to check
-bool vim_iswordc(int c)
+bool vim_iswordc(const int c)
   FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT
 {
   return vim_iswordc_buf(c, curbuf);
@@ -852,7 +852,7 @@ bool vim_iswordc_tab(const int c, const uint64_t *const chartab)
 ///
 /// @param  c    character to check
 /// @param  buf  buffer whose keywords to use
-bool vim_iswordc_buf(int c, buf_T *buf)
+bool vim_iswordc_buf(const int c, buf_T *const buf)
   FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ARG(2)
 {
   return vim_iswordc_tab(c, buf->b_chartab);
@@ -863,7 +863,7 @@ bool vim_iswordc_buf(int c, buf_T *buf)
 /// @param  p  pointer to the multi-byte character
 ///
 /// @return true if "p" points to a keyword character.
-bool vim_iswordp(char_u *p)
+bool vim_iswordp(const char_u *const p)
   FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ALL
 {
   return vim_iswordp_buf(p, curbuf);
@@ -876,7 +876,7 @@ bool vim_iswordp(char_u *p)
 /// @param  buf  buffer whose keywords to use
 ///
 /// @return true if "p" points to a keyword character.
-bool vim_iswordp_buf(char_u *p, buf_T *buf)
+bool vim_iswordp_buf(const char_u *const p, buf_T *const buf)
   FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ALL
 {
   int c = *p;
diff --git a/test/unit/mbyte_spec.lua b/test/unit/mbyte_spec.lua
index 6feef4e601..1e7e9fd6e6 100644
--- a/test/unit/mbyte_spec.lua
+++ b/test/unit/mbyte_spec.lua
@@ -5,6 +5,7 @@ local ffi     = helpers.ffi
 local eq      = helpers.eq
 
 local mbyte = helpers.cimport("./src/nvim/mbyte.h")
+local charset = helpers.cimport('./src/nvim/charset.h')
 
 describe('mbyte', function()
 
@@ -42,6 +43,15 @@ describe('mbyte', function()
     -- Sequences with more than four bytes
   end)
 
+  itp('utf_char2bytes', function()
+    local char_p = ffi.typeof('char[?]')
+    for c = 0, 0xFFFF do
+      local p = char_p(4, 0)
+      mbyte.utf_char2bytes(c, p)
+      eq(c, mbyte.utf_ptr2char(p))
+      eq(charset.vim_iswordc(c), charset.vim_iswordp(p))
+    end
+  end)
 
   describe('utfc_ptr2char_len', function()