feat: a 'disallow_case_insensetive_matching' option to fail a match on different cases

doc/cmp.txt

@@ -592,6 +592,12 @@ matching.disallow_symbol_nonprefix_matching
   `boolean`
   Whether to allow symbols in matches if the match is not a prefix match.
 
+                                cmp-config.matching.disallow_case_insensetive_matching
+matching.disallow_case_insensetive_matching
+  `boolean`
+  Whether to perform a case sensetive matching and return 0 score if the cases
+  don't match.
+
                                             *cmp-config.sorting.priority_weight*
 sorting.priority_weight~
   `number`

lua/cmp/config/default.lua

@@ -61,6 +61,7 @@ return function()
       disallow_partial_matching = false,
       disallow_prefix_unmatching = false,
       disallow_symbol_nonprefix_matching = true,
+      disallow_case_insensetive_matching = false
     },
 
     sorting = {

lua/cmp/entry.lua

@@ -393,7 +393,17 @@ end
 entry.match = function(self, input, matching_config)
   -- https://www.lua.org/pil/11.6.html
   -- do not use '..' to allocate multiple strings
-  local cache_key = string.format('%s:%d:%d:%d:%d:%d:%d', input, self.resolved_completion_item and 1 or 0, matching_config.disallow_fuzzy_matching and 1 or 0, matching_config.disallow_partial_matching and 1 or 0, matching_config.disallow_prefix_unmatching and 1 or 0, matching_config.disallow_partial_fuzzy_matching and 1 or 0, matching_config.disallow_symbol_nonprefix_matching and 1 or 0)
+
+  local cache_key = string.format('%s:%d:%d:%d:%d:%d:%d:%d',
+    input,
+    self.resolved_completion_item and 1 or 0,
+    matching_config.disallow_fuzzy_matching and 1 or 0,
+    matching_config.disallow_partial_matching and 1 or 0,
+    matching_config.disallow_prefix_unmatching and 1 or 0,
+    matching_config.disallow_partial_fuzzy_matching and 1 or 0,
+    matching_config.disallow_symbol_nonprefix_matching and 1 or 0,
+    matching_config.disallow_case_insensetive_matching and 1 or 0)
+
   local matched = self.match_cache:get(cache_key)
   if matched then
     if self.match_view_args_ret and self.match_view_args_ret.input ~= input then
@@ -417,6 +427,7 @@ entry._match = function(self, input, matching_config)
     disallow_partial_matching = matching_config.disallow_partial_matching,
     disallow_prefix_unmatching = matching_config.disallow_prefix_unmatching,
     disallow_symbol_nonprefix_matching = matching_config.disallow_symbol_nonprefix_matching,
+    disallow_case_insensentive_matching = matching_config.disallow_case_insensetive_matching,
     synonyms = {
       self.word,
       self.completion_item.label,

lua/cmp/matcher.lua

@@ -81,7 +81,7 @@ end
 ---Match entry
 ---@param input string
 ---@param word string
----@param option { synonyms: string[], disallow_fullfuzzy_matching: boolean, disallow_fuzzy_matching: boolean, disallow_partial_fuzzy_matching: boolean, disallow_partial_matching: boolean, disallow_prefix_unmatching: boolean, disallow_symbol_nonprefix_matching: boolean }
+---@param option { synonyms: string[], disallow_fullfuzzy_matching: boolean, disallow_fuzzy_matching: boolean, disallow_partial_fuzzy_matching: boolean, disallow_partial_matching: boolean, disallow_prefix_unmatching: boolean, disallow_symbol_nonprefix_matching: boolean, disallow_case_insensetive_matching: boolean}
 ---@return integer, table
 matcher.match = function(input, word, option)
   option = option or {}
@@ -98,7 +98,7 @@ matcher.match = function(input, word, option)
 
   -- Check prefix matching.
   if option.disallow_prefix_unmatching then
-    if not char.match(string.byte(input, 1), string.byte(word, 1)) then
+    if not char.match(string.byte(input, 1), string.byte(word, 1), option.disallow_case_insensetive_matching) then
       return 0, {}
     end
   end
@@ -111,7 +111,7 @@ matcher.match = function(input, word, option)
   local word_bound_index = 1
   local no_symbol_match = false
   while input_end_index <= #input and word_index <= #word do
-    local m = matcher.find_match_region(input, input_start_index, input_end_index, word, word_index)
+    local m = matcher.find_match_region(input, input_start_index, input_end_index, word, word_index, option)
     if m and input_end_index <= m.input_match_end then
       m.index = word_bound_index
       input_start_index = m.input_match_start + 1
@@ -131,7 +131,9 @@ matcher.match = function(input, word, option)
   end
 
   if #matches == 0 then
-    if not option.disallow_fuzzy_matching and not option.disallow_prefix_unmatching and not option.disallow_partial_fuzzy_matching then
+    if not option.disallow_fuzzy_matching 
+        and not option.disallow_prefix_unmatching 
+        and not option.disallow_partial_fuzzy_matching then
       if matcher.fuzzy(input, word, matches, option) then
         return 1, matches
       end
@@ -150,7 +152,8 @@ matcher.match = function(input, word, option)
       prefix = true
       local o = 1
       for i = matches[1].input_match_start, matches[1].input_match_end do
-        if not char.match(string.byte(synonym, o), string.byte(input, i)) then
+        if not char.match(string.byte(synonym, o), string.byte(input, i),
+            option.disallow_case_insensetive_matching) then
           prefix = false
           break
         end
@@ -212,7 +215,9 @@ matcher.fuzzy = function(input, word, matches, option)
     local word_offset = 0
     local word_index = char.get_next_semantic_index(word, curr_match.word_match_end)
     while word_offset + word_index < next_match.word_match_start and input_index <= #input do
-      if char.match(string.byte(word, word_index + word_offset), string.byte(input, input_index)) then
+      if char.match(string.byte(word, word_index + word_offset),
+                    string.byte(input, input_index),
+                    option.disallow_case_insensetive_matching) then
         input_index = input_index + 1
         word_offset = word_offset + 1
       else
@@ -233,7 +238,7 @@ matcher.fuzzy = function(input, word, matches, option)
   local match_count = 0
   while word_offset + word_index <= #word and input_index <= #input do
     local c1, c2 = string.byte(word, word_index + word_offset), string.byte(input, input_index)
-    if char.match(c1, c2) then
+    if char.match(c1, c2, option.disallow_case_insensetive_matching ) then
       if not matched then
         input_match_start = input_index
         word_match_start = word_index + word_offset
@@ -277,10 +282,10 @@ matcher.fuzzy = function(input, word, matches, option)
 end
 
 --- find_match_region
-matcher.find_match_region = function(input, input_start_index, input_end_index, word, word_index)
+matcher.find_match_region = function(input, input_start_index, input_end_index, word, word_index, option)
   -- determine input position ( woroff -> word_offset )
   while input_start_index < input_end_index do
-    if char.match(string.byte(input, input_end_index), string.byte(word, word_index)) then
+    if char.match(string.byte(input, input_end_index), string.byte(word, word_index), option.disallow_case_insensetive_matching) then
       break
     end
     input_end_index = input_end_index - 1
@@ -300,7 +305,7 @@ matcher.find_match_region = function(input, input_start_index, input_end_index,
   while input_index <= #input and word_index + word_offset <= #word do
     local c1 = string.byte(input, input_index)
     local c2 = string.byte(word, word_index + word_offset)
-    if char.match(c1, c2) then
+    if char.match(c1, c2, option.disallow_case_insensetive_matching) then
       -- Match start.
       if input_match_start == -1 then
         input_match_start = input_index

lua/cmp/matcher_spec.lua

@@ -52,6 +52,7 @@ describe('matcher', function()
       disallow_prefix_unmatching = false,
       disallow_partial_fuzzy_matching = false,
       disallow_symbol_nonprefix_matching = true,
+      disallow_case_insensetive_matching = false,
     })
     assert.is.truthy(score >= 1)
     assert.equals(matches[1].word_match_start, 5)
@@ -62,6 +63,7 @@ describe('matcher', function()
       disallow_prefix_unmatching = false,
       disallow_partial_fuzzy_matching = true,
       disallow_symbol_nonprefix_matching = true,
+      disallow_case_insensetive_matching = false,
     })
     assert.is.truthy(score == 0)
   end)
@@ -93,6 +95,11 @@ describe('matcher', function()
     assert.is.truthy(matcher.match('foo_', 'b foo_bar', { disallow_symbol_nonprefix_matching = false }) >= 1)
   end)
 
+  it('disallow_case_insensetive_matching', function()
+    assert.is.truthy(matcher.match('Test', 'test', { disallow_case_insensetive_matching = true }) == 0)
+    assert.is.truthy(matcher.match('Test', 'test', { disallow_case_insensetive_matching = false}) >= 1)
+  end)
+
   it('debug', function()
     matcher.debug = function(...)
       print(vim.inspect({ ... }))

lua/cmp/types/cmp.lua

@@ -146,6 +146,7 @@ cmp.ItemField = {
 ---@field public disallow_partial_matching boolean
 ---@field public disallow_prefix_unmatching boolean
 ---@field public disallow_symbol_nonprefix_matching boolean
+---@field public disallow_case_insensetive_matching boolean
 
 ---@class cmp.SortingConfig
 ---@field public priority_weight integer

lua/cmp/utils/char.lua

@@ -102,11 +102,16 @@ char.get_next_semantic_index = function(text, current_index)
   return #text + 1
 end
 
----Ignore case match
+---Ignore case match by default
 ---@param byte1 integer
 ---@param byte2 integer
+---@param is_case_sensetive boolean? default:false whether the match should be case sensetive
 ---@return boolean
-char.match = function(byte1, byte2)
+char.match = function(byte1, byte2, is_case_sensetive)
+  if is_case_sensetive then
+      return byte1 == byte2
+  end
+
   if not char.is_alpha(byte1) or not char.is_alpha(byte2) then
     return byte1 == byte2
   end