lite-xl/data/plugins/detectindent.lua

115 lines
2.9 KiB
Lua

local core = require "core"
local command = require "core.command"
local config = require "core.config"
local DocView = require "core.docview"
local Doc = require "core.doc"
local cache = setmetatable({}, { __mode = "k" })
local function add_to_stat(stat, val)
for i = 1, #stat do
if val == stat[i][1] then
stat[i][2] = stat[i][2] + 1
return
end
end
stat[#stat + 1] = {val, 1}
end
local function optimal_indent_from_stat(stat)
if #stat == 0 then return nil, 0 end
local bins = {}
for k = 1, #stat do
local indent = stat[k][1]
local score = 0
local mult_prev, lines_prev
for i = k, #stat do
if stat[i][1] % indent == 0 then
local mult = stat[i][1] / indent
if not mult_prev or (mult_prev + 1 == mult and lines_prev / stat[i][2] > 0.1) then
-- we add the number of lines to the score only if the previous
-- multiple of "indent" was populated with enough lines.
score = score + stat[i][2]
end
mult_prev, lines_prev = mult, stat[i][2]
end
end
bins[#bins + 1] = {indent, score}
end
table.sort(bins, function(a, b) return a[2] > b[2] end)
return bins[1][1], bins[1][2]
end
local auto_detect_max_lines = 400
local function detect_indent_stat(doc)
local stat = {}
local tab_count = 0
for i, text in ipairs(doc.lines) do
local str = text:match("^ %s+%S")
if str then add_to_stat(stat, #str - 1) end
local str = text:match("^\t+")
if str then tab_count = tab_count + 1 end
-- Stop parsing when files is very long. Not needed for euristic determination.
if i > auto_detect_max_lines then break end
end
table.sort(stat, function(a, b) return a[1] < b[1] end)
local indent, score = optimal_indent_from_stat(stat)
if tab_count > score then
core.log_quiet("Detect-indent: using tabs indentation")
return "hard"
elseif indent then
core.log_quiet("Detect-indent: using indentation size of %d", indent)
return "soft", indent
end
end
local function update_cache(doc)
local type, size = detect_indent_stat(doc)
if type then
cache[doc] = { type = type, size = size }
end
end
local new = Doc.new
function Doc:new(...)
new(self, ...)
update_cache(self)
end
local clean = Doc.clean
function Doc:clean(...)
clean(self, ...)
update_cache(self)
end
local function with_indent_override(doc, fn, ...)
local c = cache[doc]
if not c then
return fn(...)
end
local type, size = config.tab_type, config.indent_size
config.tab_type, config.indent_size = c.type, c.size or config.indent_size
local r1, r2, r3 = fn(...)
config.tab_type, config.indent_size = type, size
return r1, r2, r3
end
local perform = command.perform
function command.perform(...)
return with_indent_override(core.active_view.doc, perform, ...)
end
local draw = DocView.draw
function DocView:draw(...)
return with_indent_override(self.doc, draw, self, ...)
end