Added optional Lua lexer support.

This support is disabled by default and must be enabled via compile-time option.

1 files changed, 159 insertions, 0 deletions

diff --git a/lexlua/lua.lua b/lexlua/lua.lua
new file mode 100644
index 000000000..136b618da
--- /dev/null
+++ b/lexlua/lua.lua
@@ -0,0 +1,159 @@
+-- Copyright 2006-2018 Mitchell mitchell.att.foicica.com. See License.txt.
+-- Lua LPeg lexer.
+-- Original written by Peter Odding, 2007/04/04.
+
+local lexer = require('lexer')
+local token, word_match = lexer.token, lexer.word_match
+local P, R, S = lpeg.P, lpeg.R, lpeg.S
+
+local lex = lexer.new('lua')
+
+-- Whitespace.
+lex:add_rule('whitespace', token(lexer.WHITESPACE, lexer.space^1))
+
+-- Keywords.
+lex:add_rule('keyword', token(lexer.KEYWORD, word_match[[
+  and break do else elseif end false for function if in local nil not or repeat
+  return then true until while
+  -- Added in 5.2.
+  goto
+]]))
+
+-- Functions and deprecated functions.
+local func = token(lexer.FUNCTION, word_match[[
+  assert collectgarbage dofile error getmetatable ipairs load loadfile next
+  pairs pcall print rawequal rawget rawset require select setmetatable tonumber
+  tostring type xpcall
+  -- Added in 5.2.
+  rawlen
+]])
+local deprecated_func = token('deprecated_function', word_match[[
+  -- Deprecated in 5.2.
+  getfenv loadstring module setfenv unpack
+]])
+lex:add_rule('function', func + deprecated_func)
+lex:add_style('deprecated_function', lexer.STYLE_FUNCTION..',italics')
+
+-- Constants.
+lex:add_rule('constant', token(lexer.CONSTANT, word_match[[
+  _G _VERSION
+  -- Added in 5.2.
+  _ENV
+]]))
+
+-- Libraries and deprecated libraries.
+local library = token('library', word_match[[
+  -- Coroutine.
+  coroutine coroutine.create coroutine.resume coroutine.running coroutine.status
+  coroutine.wrap coroutine.yield
+  -- Coroutine added in 5.3.
+  coroutine.isyieldable
+  -- Module.
+  package package.cpath package.loaded package.loadlib package.path
+  package.preload
+  -- Module added in 5.2.
+  package.config package.searchers package.searchpath
+  -- UTF-8 added in 5.3.
+  utf8 utf8.char utf8.charpattern utf8.codepoint utf8.codes utf8.len utf8.offset
+  -- String.
+  string string.byte string.char string.dump string.find string.format
+  string.gmatch string.gsub string.len string.lower string.match string.rep
+  string.reverse string.sub string.upper
+  -- String added in 5.3.
+  string.pack string.packsize string.unpack
+  -- Table.
+  table table.concat table.insert table.remove table.sort
+  -- Table added in 5.2.
+  table.pack table.unpack
+  -- Table added in 5.3.
+  table.move
+  -- Math.
+  math math.abs math.acos math.asin math.atan math.ceil math.cos math.deg
+  math.exp math.floor math.fmod math.huge math.log math.max math.min math.modf
+  math.pi math.rad math.random math.randomseed math.sin math.sqrt math.tan
+  -- Math added in 5.3.
+  math.maxinteger math.mininteger math.tointeger math.type math.ult
+  -- IO.
+  io io.close io.flush io.input io.lines io.open io.output io.popen io.read
+  io.stderr io.stdin io.stdout io.tmpfile io.type io.write
+  -- OS.
+  os os.clock os.date os.difftime os.execute os.exit os.getenv os.remove
+  os.rename os.setlocale os.time os.tmpname
+  -- Debug.
+  debug debug.debug debug.gethook debug.getinfo debug.getlocal
+  debug.getmetatable debug.getregistry debug.getupvalue debug.sethook
+  debug.setlocal debug.setmetatable debug.setupvalue debug.traceback
+  -- Debug added in 5.2.
+  debug.getuservalue debug.setuservalue debug.upvalueid debug.upvaluejoin
+]])
+local deprecated_library = token('deprecated_library', word_match[[
+  -- Module deprecated in 5.2.
+  package.loaders package.seeall
+  -- Table deprecated in 5.2.
+  table.maxn
+  -- Math deprecated in 5.2.
+  math.log10
+  -- Math deprecated in 5.3.
+  math.atan2 math.cosh math.frexp math.ldexp math.pow math.sinh math.tanh
+  -- Bit32 deprecated in 5.3.
+  bit32 bit32.arshift bit32.band bit32.bnot bit32.bor bit32.btest bit32.extract
+  bit32.lrotate bit32.lshift bit32.replace bit32.rrotate bit32.rshift bit32.xor
+  -- Debug deprecated in 5.2.
+  debug.getfenv debug.setfenv
+]])
+lex:add_rule('library', library + deprecated_library)
+lex:add_style('library', lexer.STYLE_TYPE)
+lex:add_style('deprecated_library', lexer.STYLE_TYPE..',italics')
+
+-- Identifiers.
+lex:add_rule('identifier', token(lexer.IDENTIFIER, lexer.word))
+
+local longstring = lpeg.Cmt('[' * lpeg.C(P('=')^0) * '[',
+                            function(input, index, eq)
+                              local _, e = input:find(']'..eq..']', index, true)
+                              return (e or #input) + 1
+                            end)
+
+-- Strings.
+lex:add_rule('string', token(lexer.STRING, lexer.delimited_range("'") +
+                                           lexer.delimited_range('"')) +
+                       token('longstring', longstring))
+lex:add_style('longstring', lexer.STYLE_STRING)
+
+-- Comments.
+lex:add_rule('comment', token(lexer.COMMENT, '--' * (longstring +
+                                                     lexer.nonnewline^0)))
+
+-- Numbers.
+local lua_integer = P('-')^-1 * (lexer.hex_num + lexer.dec_num)
+lex:add_rule('number', token(lexer.NUMBER, lexer.float + lua_integer))
+
+-- Labels.
+lex:add_rule('label', token(lexer.LABEL, '::' * lexer.word * '::'))
+
+-- Operators.
+lex:add_rule('operator', token(lexer.OPERATOR, '..' +
+                                               S('+-*/%^#=<>&|~;:,.{}[]()')))
+
+-- Fold points.
+local function fold_longcomment(text, pos, line, s, symbol)
+  if symbol == '[' then
+    if line:find('^%[=*%[', s) then return 1 end
+  elseif symbol == ']' then
+    if line:find('^%]=*%]', s) then return -1 end
+  end
+  return 0
+end
+lex:add_fold_point(lexer.KEYWORD, 'if', 'end')
+lex:add_fold_point(lexer.KEYWORD, 'do', 'end')
+lex:add_fold_point(lexer.KEYWORD, 'function', 'end')
+lex:add_fold_point(lexer.KEYWORD, 'repeat', 'until')
+lex:add_fold_point(lexer.COMMENT, '[', fold_longcomment)
+lex:add_fold_point(lexer.COMMENT, ']', fold_longcomment)
+lex:add_fold_point(lexer.COMMENT, '--', lexer.fold_line_comments('--'))
+lex:add_fold_point('longstring', '[', ']')
+lex:add_fold_point(lexer.OPERATOR, '(', ')')
+lex:add_fold_point(lexer.OPERATOR, '[', ']')
+lex:add_fold_point(lexer.OPERATOR, '{', '}')
+
+return lex