3 files changed, 11 insertions, 43 deletions

diff --git a/src/nvim/mbyte_defs.h b/src/nvim/mbyte_defs.h
index e308a81a5d..8d5ff2a8c1 100644
--- a/src/nvim/mbyte_defs.h
+++ b/src/nvim/mbyte_defs.h
@@ -74,3 +74,5 @@ typedef struct {
 } CharBoundsOff;
 
 typedef utf8proc_int32_t GraphemeState;
+
+enum { UNICODE_INVALID = 0xFFFD, };
diff --git a/src/nvim/tui/termkey/termkey.c b/src/nvim/tui/termkey/termkey.c
index 8c4a91e736..eabde2f9f7 100644
--- a/src/nvim/tui/termkey/termkey.c
+++ b/src/nvim/tui/termkey/termkey.c
@@ -634,40 +634,13 @@ static void eat_bytes(TermKey *tk, size_t count)
   tk->buffcount -= count;
 }
 
-// TODO(dundargoc): we should be able to replace this with utf_char2bytes from mbyte.c
 int fill_utf8(int codepoint, char *str)
 {
-  int nbytes = utf_char2len(codepoint);
-
+  int nbytes = utf_char2bytes(codepoint, str);
   str[nbytes] = 0;
-
-  // This is easier done backwards
-  int b = nbytes;
-  while (b > 1) {
-    b--;
-    str[b] = (char)0x80 | (codepoint & 0x3f);
-    codepoint >>= 6;
-  }
-
-  switch (nbytes) {
-  case 1:
-    str[0] = (codepoint & 0x7f); break;
-  case 2:
-    str[0] = (char)0xc0 | (codepoint & 0x1f); break;
-  case 3:
-    str[0] = (char)0xe0 | (codepoint & 0x0f); break;
-  case 4:
-    str[0] = (char)0xf0 | (codepoint & 0x07); break;
-  case 5:
-    str[0] = (char)0xf8 | (codepoint & 0x03); break;
-  case 6:
-    str[0] = (char)0xfc | (codepoint & 0x01); break;
-  }
-
   return nbytes;
 }
 
-#define UTF8_INVALID 0xFFFD
 static TermKeyResult parse_utf8(const unsigned char *bytes, size_t len, int *cp, size_t *nbytep)
 {
   unsigned nbytes;
@@ -681,7 +654,7 @@ static TermKeyResult parse_utf8(const unsigned char *bytes, size_t len, int *cp,
     return TERMKEY_RES_KEY;
   } else if (b0 < 0xc0) {
     // Starts with a continuation byte - that's not right
-    *cp = UTF8_INVALID;
+    *cp = UNICODE_INVALID;
     *nbytep = 1;
     return TERMKEY_RES_KEY;
   } else if (b0 < 0xe0) {
@@ -700,7 +673,7 @@ static TermKeyResult parse_utf8(const unsigned char *bytes, size_t len, int *cp,
     nbytes = 6;
     *cp = b0 & 0x01;
   } else {
-    *cp = UTF8_INVALID;
+    *cp = UNICODE_INVALID;
     *nbytep = 1;
     return TERMKEY_RES_KEY;
   }
@@ -714,7 +687,7 @@ static TermKeyResult parse_utf8(const unsigned char *bytes, size_t len, int *cp,
 
     cb = bytes[b];
     if (cb < 0x80 || cb >= 0xc0) {
-      *cp = UTF8_INVALID;
+      *cp = UNICODE_INVALID;
       *nbytep = b;
       return TERMKEY_RES_KEY;
     }
@@ -725,14 +698,14 @@ static TermKeyResult parse_utf8(const unsigned char *bytes, size_t len, int *cp,
 
   // Check for overlong sequences
   if ((int)nbytes > utf_char2len(*cp)) {
-    *cp = UTF8_INVALID;
+    *cp = UNICODE_INVALID;
   }
 
   // Check for UTF-16 surrogates or invalid *cps
   if ((*cp >= 0xD800 && *cp <= 0xDFFF)
       || *cp == 0xFFFE
       || *cp == 0xFFFF) {
-    *cp = UTF8_INVALID;
+    *cp = UNICODE_INVALID;
   }
 
   *nbytep = nbytes;
@@ -962,9 +935,9 @@ static TermKeyResult peekkey_simple(TermKey *tk, TermKeyKey *key, int force, siz
     if (res == TERMKEY_RES_AGAIN && force) {
       // There weren't enough bytes for a complete UTF-8 sequence but caller
       // demands an answer. About the best thing we can do here is eat as many
-      // bytes as we have, and emit a UTF8_INVALID. If the remaining bytes
+      // bytes as we have, and emit a UNICODE_INVALID. If the remaining bytes
       // arrive later, they'll be invalid too.
-      codepoint = UTF8_INVALID;
+      codepoint = UNICODE_INVALID;
       *nbytep = tk->buffcount;
       res = TERMKEY_RES_KEY;
     }
diff --git a/src/nvim/vterm/encoding.c b/src/nvim/vterm/encoding.c
index cc3208cfa2..f9061e8e50 100644
--- a/src/nvim/vterm/encoding.c
+++ b/src/nvim/vterm/encoding.c
@@ -210,6 +210,7 @@ static void decode_table(VTermEncoding *enc, void *data, uint32_t cp[], int *cpi
   }
 }
 
+// https://en.wikipedia.org/wiki/DEC_Special_Graphics
 static const struct StaticTableEncoding encoding_DECdrawing = {
   { .decode = &decode_table },
   {
@@ -247,13 +248,6 @@ static const struct StaticTableEncoding encoding_DECdrawing = {
   }
 };
 
-static const struct StaticTableEncoding encoding_uk = {
-  { .decode = &decode_table },
-  {
-    [0x23] = 0x00a3,  // £
-  }
-};
-
 static struct {
   VTermEncodingType type;
   char designation;
@@ -262,7 +256,6 @@ static struct {
 encodings[] = {
   { ENC_UTF8,      'u', &encoding_utf8 },
   { ENC_SINGLE_94, '0', (VTermEncoding *)&encoding_DECdrawing },
-  { ENC_SINGLE_94, 'A', (VTermEncoding *)&encoding_uk },
   { ENC_SINGLE_94, 'B', &encoding_usascii },
   { 0 },
 };