Add stage 06: Lua bootstrap

The goal of stage 06 is to try parse zig synax in lua. I pulled in
lpeglable 1.2.0 and parser-gen off github to get started. All of this
needs to be cleaned up rather soon.

Lua boostraps using tcc and musl from the previous stage. Since musl
0.6.0 doesn't support dynamic linking this build of lua doesn't support
shared libraries. I couldn't easily patch musl with dlopen and friends
so instead I link statically and call deps with c api.

06/parser-gen/parsers/lua-5.3.4-tests/utf8.lua

@@ -0,0 +1,210 @@
+-- $Id: utf8.lua,v 1.12 2016/11/07 13:11:28 roberto Exp $
+-- See Copyright Notice in file all.lua
+
+print "testing UTF-8 library"
+
+local utf8 = require'utf8'
+
+
+local function checkerror (msg, f, ...)
+  local s, err = pcall(f, ...)
+  assert(not s and string.find(err, msg))
+end
+
+
+local function len (s)
+  return #string.gsub(s, "[\x80-\xBF]", "")
+end
+
+
+local justone = "^" .. utf8.charpattern .. "$"
+
+-- 't' is the list of codepoints of 's'
+local function checksyntax (s, t)
+  local ts = {"return '"}
+  for i = 1, #t do ts[i + 1] = string.format("\\u{%x}", t[i]) end
+  ts[#t + 2] = "'"
+  ts = table.concat(ts)
+  assert(assert(load(ts))() == s)
+end
+
+assert(utf8.offset("alo", 5) == nil)
+assert(utf8.offset("alo", -4) == nil)
+
+-- 't' is the list of codepoints of 's'
+local function check (s, t)
+  local l = utf8.len(s) 
+  assert(#t == l and len(s) == l)
+  assert(utf8.char(table.unpack(t)) == s)
+
+  assert(utf8.offset(s, 0) == 1)
+
+  checksyntax(s, t)
+
+  local t1 = {utf8.codepoint(s, 1, -1)}
+  assert(#t == #t1)
+  for i = 1, #t do assert(t[i] == t1[i]) end
+
+  for i = 1, l do
+    local pi = utf8.offset(s, i)        -- position of i-th char
+    local pi1 = utf8.offset(s, 2, pi)   -- position of next char
+    assert(string.find(string.sub(s, pi, pi1 - 1), justone))
+    assert(utf8.offset(s, -1, pi1) == pi)
+    assert(utf8.offset(s, i - l - 1) == pi)
+    assert(pi1 - pi == #utf8.char(utf8.codepoint(s, pi)))
+    for j = pi, pi1 - 1 do 
+      assert(utf8.offset(s, 0, j) == pi)
+    end
+    for j = pi + 1, pi1 - 1 do
+      assert(not utf8.len(s, j))
+    end
+   assert(utf8.len(s, pi, pi) == 1)
+   assert(utf8.len(s, pi, pi1 - 1) == 1)
+   assert(utf8.len(s, pi) == l - i + 1)
+   assert(utf8.len(s, pi1) == l - i)
+   assert(utf8.len(s, 1, pi) == i)
+  end
+
+  local i = 0
+  for p, c in utf8.codes(s) do
+    i = i + 1
+    assert(c == t[i] and p == utf8.offset(s, i))
+    assert(utf8.codepoint(s, p) == c)
+  end
+  assert(i == #t)
+
+  i = 0
+  for p, c in utf8.codes(s) do
+    i = i + 1
+    assert(c == t[i] and p == utf8.offset(s, i)) 
+  end
+  assert(i == #t)
+
+  i = 0
+  for c in string.gmatch(s, utf8.charpattern) do
+    i = i + 1
+    assert(c == utf8.char(t[i]))
+  end
+  assert(i == #t)
+
+  for i = 1, l do
+    assert(utf8.offset(s, i) == utf8.offset(s, i - l - 1, #s + 1))
+  end
+
+end
+
+
+do    -- error indication in utf8.len
+  local function check (s, p)
+    local a, b = utf8.len(s)
+    assert(not a and b == p)
+  end
+  check("abc\xE3def", 4)
+  check("汉字\x80", #("汉字") + 1)
+  check("\xF4\x9F\xBF", 1)
+  check("\xF4\x9F\xBF\xBF", 1)
+end
+
+-- error in utf8.codes
+checkerror("invalid UTF%-8 code",
+  function ()
+    local s = "ab\xff"
+    for c in utf8.codes(s) do assert(c) end
+  end)
+
+
+-- error in initial position for offset
+checkerror("position out of range", utf8.offset, "abc", 1, 5)
+checkerror("position out of range", utf8.offset, "abc", 1, -4)
+checkerror("position out of range", utf8.offset, "", 1, 2)
+checkerror("position out of range", utf8.offset, "", 1, -1)
+checkerror("continuation byte", utf8.offset, "𦧺", 1, 2)
+checkerror("continuation byte", utf8.offset, "𦧺", 1, 2)
+checkerror("continuation byte", utf8.offset, "\x80", 1)
+
+
+
+local s = "hello World"
+local t = {string.byte(s, 1, -1)}
+for i = 1, utf8.len(s) do assert(t[i] == string.byte(s, i)) end
+check(s, t)
+
+check("汉字/漢字", {27721, 23383, 47, 28450, 23383,})
+
+do
+  local s = "áéí\128"
+  local t = {utf8.codepoint(s,1,#s - 1)}
+  assert(#t == 3 and t[1] == 225 and t[2] == 233 and t[3] == 237)
+  checkerror("invalid UTF%-8 code", utf8.codepoint, s, 1, #s)
+  checkerror("out of range", utf8.codepoint, s, #s + 1)
+  t = {utf8.codepoint(s, 4, 3)}
+  assert(#t == 0)
+  checkerror("out of range", utf8.codepoint, s, -(#s + 1), 1)
+  checkerror("out of range", utf8.codepoint, s, 1, #s + 1)
+end
+
+assert(utf8.char() == "")
+assert(utf8.char(97, 98, 99) == "abc")
+
+assert(utf8.codepoint(utf8.char(0x10FFFF)) == 0x10FFFF)
+
+checkerror("value out of range", utf8.char, 0x10FFFF + 1)
+
+local function invalid (s)
+  checkerror("invalid UTF%-8 code", utf8.codepoint, s)
+  assert(not utf8.len(s))
+end
+
+-- UTF-8 representation for 0x11ffff (value out of valid range)
+invalid("\xF4\x9F\xBF\xBF")
+
+-- overlong sequences
+invalid("\xC0\x80")          -- zero
+invalid("\xC1\xBF")          -- 0x7F (should be coded in 1 byte)
+invalid("\xE0\x9F\xBF")      -- 0x7FF (should be coded in 2 bytes)
+invalid("\xF0\x8F\xBF\xBF")  -- 0xFFFF (should be coded in 3 bytes)
+
+
+-- invalid bytes
+invalid("\x80")  -- continuation byte
+invalid("\xBF")  -- continuation byte
+invalid("\xFE")  -- invalid byte
+invalid("\xFF")  -- invalid byte
+
+
+-- empty string
+check("", {})
+
+-- minimum and maximum values for each sequence size
+s = "\0 \x7F\z
+     \xC2\x80 \xDF\xBF\z
+     \xE0\xA0\x80 \xEF\xBF\xBF\z
+     \xF0\x90\x80\x80  \xF4\x8F\xBF\xBF"
+s = string.gsub(s, " ", "")
+check(s, {0,0x7F, 0x80,0x7FF, 0x800,0xFFFF, 0x10000,0x10FFFF})
+
+x = "日本語a-4\0éó"
+check(x, {26085, 26412, 35486, 97, 45, 52, 0, 233, 243})
+
+
+-- Supplementary Characters
+check("𣲷𠜎𠱓𡁻𠵼ab𠺢",
+      {0x23CB7, 0x2070E, 0x20C53, 0x2107B, 0x20D7C, 0x61, 0x62, 0x20EA2,})
+
+check("𨳊𩶘𦧺𨳒𥄫𤓓\xF4\x8F\xBF\xBF",
+      {0x28CCA, 0x29D98, 0x269FA, 0x28CD2, 0x2512B, 0x244D3, 0x10ffff})
+
+
+local i = 0
+for p, c in string.gmatch(x, "()(" .. utf8.charpattern .. ")") do
+  i = i + 1
+  assert(utf8.offset(x, i) == p)
+  assert(utf8.len(x, p) == utf8.len(x) - i + 1)
+  assert(utf8.len(c) == 1)
+  for j = 1, #c - 1 do
+    assert(utf8.offset(x, 0, p + j - 1) == p)
+  end
+end
+
+print'ok'
+