1 files changed, 59 insertions, 22 deletions
diff --git a/src/gen/gen_keycodes.lua b/src/gen/gen_keycodes.lua
index 118eac2579..53f0c24e58 100644
--- a/src/gen/gen_keycodes.lua
+++ b/src/gen/gen_keycodes.lua
@@ -1,49 +1,86 @@
 local names_file = arg[1]
 
+local hashy = require('gen.hashy')
 local keycodes = require('nvim.keycodes')
 
-local names_tgt = assert(io.open(names_file, 'w'))
+local keycode_names = keycodes.names
 
---- @type [string, string, integer][]
-local keycode_names = {}
-for i, keycode in ipairs(keycodes.names) do
-  table.insert(keycode_names, { keycode[1], keycode[2], i })
-end
-table.sort(keycode_names, function(keycode_a, keycode_b)
-  return keycode_a[2]:lower() < keycode_b[2]:lower()
-end)
+--- @type table<string,integer>
+--- Maps lower-case key names to their original indexes.
+local name_orig_idx = {}
 
 --- @type table<string,integer>
-local alt_name_idx = {}
+--- Maps keys to the original indexes of their preferred names.
+local key_orig_idx = {}
+
+--- @type [string, string][]
+--- When multiple keys have the same name (e.g. TAB and K_TAB), only the first one
+--- is added to the two tables above, and the other keys are added here.
+local extra_keys = {}
+
 for i, keycode in ipairs(keycode_names) do
   local key = keycode[1]
-  local alt_idx = alt_name_idx[key]
-  if alt_idx == nil or keycode_names[alt_idx][3] > keycode[3] then
-    alt_name_idx[key] = i
+  local name = keycode[2]
+  local name_lower = name:lower()
+  if name_orig_idx[name_lower] == nil then
+    name_orig_idx[name_lower] = i
+    if key_orig_idx[key] == nil then
+      key_orig_idx[key] = i
+    end
+  else
+    table.insert(extra_keys, keycode)
+  end
+end
+
+local hashorder = vim.tbl_keys(name_orig_idx)
+table.sort(hashorder)
+local hashfun
+hashorder, hashfun = hashy.hashy_hash('get_special_key_code', hashorder, function(idx)
+  return 'key_names_table[' .. idx .. '].name.data'
+end, true)
+
+--- @type table<string,integer>
+--- Maps keys to the (after hash) indexes of the entries with preferred names.
+local key_hash_idx = {}
+
+for i, lower_name in ipairs(hashorder) do
+  local orig_idx = name_orig_idx[lower_name]
+  local key = keycode_names[orig_idx][1]
+  if key_orig_idx[key] == orig_idx then
+    key_hash_idx[key] = i
   end
 end
 
+local names_tgt = assert(io.open(names_file, 'w'))
 names_tgt:write([[
 static const struct key_name_entry {
-  int key;                 ///< Special key code or ascii value
-  String name;             ///< Name of key
-  const String *alt_name;  ///< Pointer to alternative key name
-                           ///< (may be NULL or point to the name in another entry)
+  int key;                  ///< Special key code or ascii value
+  String name;              ///< Name of key
+  const String *pref_name;  ///< Pointer to preferred key name
+                            ///< (may be NULL or point to the name in another entry)
 } key_names_table[] = {]])
 
-for i, keycode in ipairs(keycode_names) do
+for i, lower_name in ipairs(hashorder) do
+  local keycode = keycode_names[name_orig_idx[lower_name]]
   local key = keycode[1]
   local name = keycode[2]
-  local alt_idx = alt_name_idx[key]
+  local pref_idx = key_hash_idx[key]
   names_tgt:write(
-    ('\n  {%s, {"%s", %d}, %s},'):format(
+    ('\n  {%s, {"%s", %u}, %s},'):format(
       key,
       name,
       #name,
-      alt_idx == i and 'NULL' or ('&key_names_table[%d].name'):format(alt_idx - 1)
+      pref_idx == i and 'NULL' or ('&key_names_table[%u].name'):format(pref_idx - 1)
     )
   )
 end
 
-names_tgt:write('\n};\n')
+for _, keycode in ipairs(extra_keys) do
+  local key = keycode[1]
+  local name = keycode[2]
+  names_tgt:write(('\n  {%s, {"%s", %u}, NULL},'):format(key, name, #name))
+end
+
+names_tgt:write('\n};\n\n')
+names_tgt:write('static ' .. hashfun)
 names_tgt:close()