feat: use improved telescope's matcher (#184)

ref #177
ref https://github.com/nvim-telescope/telescope.nvim/pull/2950

Now telescope has the same matcher as the one #177 has introduced. This
commit makes it use that.

lua/frecency/picker.lua

@@ -1,6 +1,6 @@
 local State = require "frecency.state"
 local Finder = require "frecency.finder"
-local sorters = require "frecency.sorters"
+local sorters = require "telescope.sorters"
 local log = require "plenary.log"
 local Path = require "plenary.path" --[[@as PlenaryPath]]
 local actions = require "telescope.actions"
@@ -110,7 +110,7 @@ function Picker:start(opts)
     prompt_title = "Frecency",
     finder = finder,
     previewer = config_values.file_previewer(opts),
-    sorter = sorters.get_frecency_matcher(),
+    sorter = sorters.get_substr_matcher(),
     on_input_filter_cb = self:on_input_filter_cb(opts),
     attach_mappings = function(prompt_bufnr)
       return self:attach_mappings(prompt_bufnr)

lua/frecency/sorters.lua

@@ -1,63 +0,0 @@
-local sorters = require "telescope.sorters"
-local util = require "telescope.utils"
-
-local M = {}
-
----@param prompt string
----@return boolean
-local function has_upper_case(prompt)
-  return not not prompt:match "%u"
-end
-
----@param prompt string
----@param display string
----@return { start: integer, finish: integer }[]
-local function highlighter(_, prompt, display)
-  ---@type { start: integer, finish: integer }[]
-  local highlights = {}
-  display = has_upper_case(prompt) and display or display:lower()
-
-  local search_terms = util.max_split(prompt, "%s")
-  local hl_start, hl_end
-
-  for _, word in ipairs(search_terms) do
-    hl_start, hl_end = display:find(word, 1, true)
-    if hl_start then
-      table.insert(highlights, { start = hl_start, finish = hl_end })
-    end
-  end
-
-  return highlights
-end
-
----@param prompt string
----@param entry FrecencyEntry
----@return integer
-local function scoring_function(_, prompt, _, entry)
-  if #prompt == 0 then
-    return 1
-  end
-
-  local display = has_upper_case(prompt) and entry.ordinal or entry.ordinal:lower()
-
-  local search_terms = util.max_split(prompt, "%s")
-  for _, word in ipairs(search_terms) do
-    if not display:find(word, 1, true) then
-      return -1
-    end
-  end
-  return entry.index
-end
-
----This is a sorter similar to telescope.sorters.get_substr_matcher. telescope's
----one always ignore cases, but this sorter deal with them like 'smartcase' way.
-function M.get_frecency_matcher()
-  return vim.o.smartcase
-      and sorters.Sorter:new {
-        highlighter = highlighter,
-        scoring_function = scoring_function,
-      }
-    or sorters.get_substr_matcher()
-end
-
-return M