Added macro 'luaL_pushfail'

The macro 'luaL_pushfail' documents all places in the standard libraries
that return nil to signal some kind of failure. It is defined as
'lua_pushnil'. The manual also got a notation (@fail) to document those
returns. The tests were changed to be agnostic regarding whether 'fail'
is 'nil' or 'false'.

9 files changed, 91 insertions, 91 deletions

diff --git a/testes/api.lua b/testes/api.lua
index 4f9d6717..b2680633 100644
--- a/testes/api.lua
+++ b/testes/api.lua
@@ -698,7 +698,7 @@ for k, v in ipairs(t) do
   assert(v1 == v and p)
 end
 
-assert(debug.getuservalue(4) == nil)
+assert(not debug.getuservalue(4))
 
 debug.setuservalue(b, function () return 10 end, 10)
 collectgarbage()   -- function should not be collected
diff --git a/testes/db.lua b/testes/db.lua
index a64a1130..c43243a6 100644
--- a/testes/db.lua
+++ b/testes/db.lua
@@ -351,12 +351,12 @@ assert(g(0,0) == 30)
  
 
 debug.sethook(nil);
-assert(debug.gethook() == nil)
+assert(not debug.gethook())
 
 
 -- minimal tests for setuservalue/getuservalue
 do
-  assert(debug.setuservalue(io.stdin, 10) == nil)
+  assert(not debug.setuservalue(io.stdin, 10))
   local a, b = debug.getuservalue(io.stdin, 10)
   assert(a == nil and not b)
 end
@@ -414,7 +414,7 @@ end, "c")
 a:f(1,2,3,4,5)
 assert(X.self == a and X.a == 1   and X.b == 2 and X.c == nil)
 assert(XX == 12)
-assert(debug.gethook() == nil)
+assert(not debug.gethook())
 
 
 -- testing access to local variables in return hook (bug in 5.2)
diff --git a/testes/errors.lua b/testes/errors.lua
index 6e7b8004..f9623b1d 100644
--- a/testes/errors.lua
+++ b/testes/errors.lua
@@ -18,7 +18,7 @@ end
 
 local function doit (s)
   local f, msg = load(s)
-  if f == nil then return msg end
+  if not f then return msg end
   local cond, msg = pcall(f)
   return (not cond) and msg
 end
@@ -312,8 +312,8 @@ end
 
 local function lineerror (s, l)
   local err,msg = pcall(load(s))
-  local line = string.match(msg, ":(%d+):")
-  assert(tonumber(line) == l)
+  local line = tonumber(string.match(msg, ":(%d+):"))
+  assert(line == l or (not line and not l))
 end
 
 lineerror("local a\n for i=1,'a' do \n print(i) \n end", 2)
@@ -359,7 +359,7 @@ local p = [[
 g()
 ]]
 X=3;lineerror((p), 3)
-X=0;lineerror((p), nil)
+X=0;lineerror((p), false)
 X=1;lineerror((p), 2)
 X=2;lineerror((p), 1)
 
@@ -510,7 +510,7 @@ checksyntax("a\1a = 1", "", "<\\1>", 1)
 checksyntax("\255a = 1", "", "<\\255>", 1)
 
 doit('I = load("a=9+"); a=3')
-assert(a==3 and I == nil)
+assert(a==3 and not I)
 print('+')
 
 lim = 1000
diff --git a/testes/files.lua b/testes/files.lua
index 585e5948..677c0dc2 100644
--- a/testes/files.lua
+++ b/testes/files.lua
@@ -184,7 +184,7 @@ three
   local f <close> = assert(io.open(file, "r"))
   -- second item failing
   l1, n1, n2, dummy = f:read("l", "n", "n", "l")
-  assert(l1 == "a line" and n1 == nil)
+  assert(l1 == "a line" and not n1)
 end
 assert(os.remove(file))
 
@@ -228,7 +228,7 @@ assert(f:read("n") == 0Xdeadbeefdeadbeef); assert(f:read(2) == "x\n")
 assert(f:read("n") == 0x1.13aP3); assert(f:read(1) == "e")
 
 do   -- attempt to read too long number
-  assert(f:read("n") == nil)  -- fails
+  assert(not f:read("n"))  -- fails
   local s = f:read("L")   -- read rest of line
   assert(string.find(s, "^00*\n$"))  -- lots of 0's left
 end
@@ -314,13 +314,13 @@ assert(io.read() == "fourth_line")
 assert(io.read() == "")  -- empty line
 assert(io.read('n') == 3450)
 assert(io.read(1) == '\n')
-assert(io.read(0) == nil)  -- end of file
-assert(io.read(1) == nil)  -- end of file
-assert(io.read(30000) == nil)  -- end of file
+assert(not io.read(0))  -- end of file
+assert(not io.read(1))  -- end of file
+assert(not io.read(30000))  -- end of file
 assert(({io.read(1)})[2] == undef)
-assert(io.read() == nil)  -- end of file
+assert(not io.read())  -- end of file
 assert(({io.read()})[2] == undef)
-assert(io.read('n') == nil)  -- end of file
+assert(not io.read('n'))  -- end of file
 assert(({io.read('n')})[2] == undef)
 assert(io.read('a') == '')  -- end of file (OK for 'a')
 assert(io.read('a') == '')  -- end of file (OK for 'a')
@@ -356,7 +356,7 @@ assert(io.read(string.len(t)) == t)
 assert(io.read(1) == ' ')
 assert(io.read(0))
 assert(io.read('a') == ';end of file\n')
-assert(io.read(0) == nil)
+assert(not io.read(0))
 assert(io.close(io.input()))
 
 
@@ -364,7 +364,7 @@ assert(io.close(io.input()))
 do
   local function ismsg (m)
     -- error message is not a code number
-    return (type(m) == "string" and tonumber(m) == nil)
+    return (type(m) == "string" and not tonumber(m))
   end
 
   -- read
@@ -393,7 +393,7 @@ assert(io.read"L" == "\n")
 assert(io.read"L" == "\n")
 assert(io.read"L" == "line\n")
 assert(io.read"L" == "other")
-assert(io.read"L" == nil)
+assert(not io.read"L")
 io.input():close()
 
 local f = assert(io.open(file))
@@ -462,7 +462,7 @@ end
 -- test for multipe arguments in 'lines'
 io.output(file); io.write"0123456789\n":close()
 for a,b in io.lines(file, 1, 1) do
-  if a == "\n" then assert(b == nil)
+  if a == "\n" then assert(not b)
   else assert(tonumber(a) == tonumber(b) - 1)
   end
 end
@@ -473,13 +473,13 @@ end
 
 for a,b,c in io.lines(file, "a", 0, 1) do
   if a == "" then break end
-  assert(a == "0123456789\n" and b == nil and c == nil)
+  assert(a == "0123456789\n" and not b and not c)
 end
 collectgarbage()   -- to close file in previous iteration
 
 io.output(file); io.write"00\n10\n20\n30\n40\n":close()
 for a, b in io.lines(file, "n", "n") do
-  if a == 40 then assert(b == nil)
+  if a == 40 then assert(not b)
   else assert(a == b - 10)
   end
 end
@@ -654,7 +654,7 @@ and the rest of the file
 io.input(file)
 local _,a,b,c,d,e,h,__ = io.read(1, 'n', 'n', 'l', 'l', 'l', 'a', 10)
 assert(io.close(io.input()))
-assert(_ == ' ' and __ == nil)
+assert(_ == ' ' and not __)
 assert(type(a) == 'number' and a==123.4 and b==-56e-2)
 assert(d=='second line' and e=='third line')
 assert(h==[[
@@ -706,7 +706,7 @@ if not _soft then
   io.input():seek('set', 0)
   y = io.read()  -- huge line
   assert(x == y..'\n'..io.read())
-  assert(io.read() == nil)
+  assert(not io.read())
   io.close(io.input())
   assert(os.remove(file))
   x = nil; y = nil
diff --git a/testes/literals.lua b/testes/literals.lua
index 27f9377d..e101eabf 100644
--- a/testes/literals.lua
+++ b/testes/literals.lua
@@ -281,7 +281,7 @@ if os.setlocale("pt_BR") or os.setlocale("ptb") then
 
   assert(" 0x.1 " + " 0x,1" + "-0X.1\t" == 0x0.1)
 
-  assert(tonumber"inf" == nil and tonumber"NAN" == nil)
+  assert(not tonumber"inf" and not tonumber"NAN")
 
   assert(assert(load(string.format("return %q", 4.51)))() == 4.51)
 
diff --git a/testes/math.lua b/testes/math.lua
index bad43901..c7dc8285 100644
--- a/testes/math.lua
+++ b/testes/math.lua
@@ -39,7 +39,7 @@ do
 end
 
 assert(math.type(0) == "integer" and math.type(0.0) == "float"
-       and math.type("10") == nil)
+       and not math.type("10"))
 
 
 local function checkerror (msg, f, ...)
@@ -381,17 +381,17 @@ assert(tonumber(1/0) == 1/0)
 
 -- 'tonumber' with strings
 assert(tonumber("0") == 0)
-assert(tonumber("") == nil)
-assert(tonumber("  ") == nil)
-assert(tonumber("-") == nil)
-assert(tonumber("  -0x ") == nil)
-assert(tonumber{} == nil)
+assert(not tonumber(""))
+assert(not tonumber("  "))
+assert(not tonumber("-"))
+assert(not tonumber("  -0x "))
+assert(not tonumber{})
 assert(tonumber'+0.01' == 1/100 and tonumber'+.01' == 0.01 and
        tonumber'.01' == 0.01    and tonumber'-1.' == -1 and
        tonumber'+1.' == 1)
-assert(tonumber'+ 0.01' == nil and tonumber'+.e1' == nil and
-       tonumber'1e' == nil     and tonumber'1.0e+' == nil and
-       tonumber'.' == nil)
+assert(not tonumber'+ 0.01' and not tonumber'+.e1' and
+       not tonumber'1e'     and not tonumber'1.0e+' and
+       not tonumber'.')
 assert(tonumber('-012') == -010-2)
 assert(tonumber('-1.2e2') == - - -120)
 
@@ -445,45 +445,45 @@ local function f (...)
   end
 end
 
-assert(f(tonumber('fFfa', 15)) == nil)
-assert(f(tonumber('099', 8)) == nil)
-assert(f(tonumber('1\0', 2)) == nil)
-assert(f(tonumber('', 8)) == nil)
-assert(f(tonumber('  ', 9)) == nil)
-assert(f(tonumber('  ', 9)) == nil)
-assert(f(tonumber('0xf', 10)) == nil)
+assert(not f(tonumber('fFfa', 15)))
+assert(not f(tonumber('099', 8)))
+assert(not f(tonumber('1\0', 2)))
+assert(not f(tonumber('', 8)))
+assert(not f(tonumber('  ', 9)))
+assert(not f(tonumber('  ', 9)))
+assert(not f(tonumber('0xf', 10)))
 
-assert(f(tonumber('inf')) == nil)
-assert(f(tonumber(' INF ')) == nil)
-assert(f(tonumber('Nan')) == nil)
-assert(f(tonumber('nan')) == nil)
+assert(not f(tonumber('inf')))
+assert(not f(tonumber(' INF ')))
+assert(not f(tonumber('Nan')))
+assert(not f(tonumber('nan')))
 
-assert(f(tonumber('  ')) == nil)
-assert(f(tonumber('')) == nil)
-assert(f(tonumber('1  a')) == nil)
-assert(f(tonumber('1  a', 2)) == nil)
-assert(f(tonumber('1\0')) == nil)
-assert(f(tonumber('1 \0')) == nil)
-assert(f(tonumber('1\0 ')) == nil)
-assert(f(tonumber('e1')) == nil)
-assert(f(tonumber('e  1')) == nil)
-assert(f(tonumber(' 3.4.5 ')) == nil)
+assert(not f(tonumber('  ')))
+assert(not f(tonumber('')))
+assert(not f(tonumber('1  a')))
+assert(not f(tonumber('1  a', 2)))
+assert(not f(tonumber('1\0')))
+assert(not f(tonumber('1 \0')))
+assert(not f(tonumber('1\0 ')))
+assert(not f(tonumber('e1')))
+assert(not f(tonumber('e  1')))
+assert(not f(tonumber(' 3.4.5 ')))
 
 
 -- testing 'tonumber' for invalid hexadecimal formats
 
-assert(tonumber('0x') == nil)
-assert(tonumber('x') == nil)
-assert(tonumber('x3') == nil)
-assert(tonumber('0x3.3.3') == nil)   -- two decimal points
-assert(tonumber('00x2') == nil)
-assert(tonumber('0x 2') == nil)
-assert(tonumber('0 x2') == nil)
-assert(tonumber('23x') == nil)
-assert(tonumber('- 0xaa') == nil)
-assert(tonumber('-0xaaP ') == nil)   -- no exponent
-assert(tonumber('0x0.51p') == nil)
-assert(tonumber('0x5p+-2') == nil)
+assert(not tonumber('0x'))
+assert(not tonumber('x'))
+assert(not tonumber('x3'))
+assert(not tonumber('0x3.3.3'))   -- two decimal points
+assert(not tonumber('00x2'))
+assert(not tonumber('0x 2'))
+assert(not tonumber('0 x2'))
+assert(not tonumber('23x'))
+assert(not tonumber('- 0xaa'))
+assert(not tonumber('-0xaaP '))   -- no exponent
+assert(not tonumber('0x0.51p'))
+assert(not tonumber('0x5p+-2'))
 
 
 -- testing hexadecimal numerals
@@ -705,19 +705,19 @@ do   -- testing floor & ceil
   assert(eqT(math.tointeger(maxint), maxint))
   assert(eqT(math.tointeger(maxint .. ""), maxint))
   assert(eqT(math.tointeger(minint + 0.0), minint))
-  assert(math.tointeger(0.0 - minint) == nil)
-  assert(math.tointeger(math.pi) == nil)
-  assert(math.tointeger(-math.pi) == nil)
+  assert(not math.tointeger(0.0 - minint))
+  assert(not math.tointeger(math.pi))
+  assert(not math.tointeger(-math.pi))
   assert(math.floor(math.huge) == math.huge)
   assert(math.ceil(math.huge) == math.huge)
-  assert(math.tointeger(math.huge) == nil)
+  assert(not math.tointeger(math.huge))
   assert(math.floor(-math.huge) == -math.huge)
   assert(math.ceil(-math.huge) == -math.huge)
-  assert(math.tointeger(-math.huge) == nil)
+  assert(not math.tointeger(-math.huge))
   assert(math.tointeger("34.0") == 34)
-  assert(math.tointeger("34.3") == nil)
-  assert(math.tointeger({}) == nil)
-  assert(math.tointeger(0/0) == nil)    -- NaN
+  assert(not math.tointeger("34.3"))
+  assert(not math.tointeger({}))
+  assert(not math.tointeger(0/0))    -- NaN
 end
 
 
diff --git a/testes/pm.lua b/testes/pm.lua
index 4d87fad2..94bb63ca 100644
--- a/testes/pm.lua
+++ b/testes/pm.lua
@@ -28,10 +28,10 @@ a,b = string.find('a\0a\0a\0a\0\0ab', '\0ab', 2);  -- finds at the end
 assert(a == 9 and b == 11);
 a,b = string.find('a\0a\0a\0a\0\0ab', 'b')    -- last position
 assert(a == 11 and b == 11)
-assert(string.find('a\0a\0a\0a\0\0ab', 'b\0') == nil)   -- check ending
-assert(string.find('', '\0') == nil)
+assert(not string.find('a\0a\0a\0a\0\0ab', 'b\0'))   -- check ending
+assert(not string.find('', '\0'))
 assert(string.find('alo123alo', '12') == 4)
-assert(string.find('alo123alo', '^12') == nil)
+assert(not string.find('alo123alo', '^12'))
 
 assert(string.match("aaab", ".*b") == "aaab")
 assert(string.match("aaa", ".*a") == "aaa")
@@ -57,17 +57,17 @@ assert(f('aaa', 'ab*a') == 'aa')
 assert(f('aba', 'ab*a') == 'aba')
 assert(f('aaab', 'a+') == 'aaa')
 assert(f('aaa', '^.+$') == 'aaa')
-assert(f('aaa', 'b+') == nil)
-assert(f('aaa', 'ab+a') == nil)
+assert(not f('aaa', 'b+'))
+assert(not f('aaa', 'ab+a'))
 assert(f('aba', 'ab+a') == 'aba')
 assert(f('a$a', '.$') == 'a')
 assert(f('a$a', '.%$') == 'a$')
 assert(f('a$a', '.$.') == 'a$a')
-assert(f('a$a', '$$') == nil)
-assert(f('a$b', 'a$') == nil)
+assert(not f('a$a', '$$'))
+assert(not f('a$b', 'a$'))
 assert(f('a$a', '$') == '')
 assert(f('', 'b*') == '')
-assert(f('aaa', 'bb*') == nil)
+assert(not f('aaa', 'bb*'))
 assert(f('aaab', 'a-') == '')
 assert(f('aaa', '^.-$') == 'aaa')
 assert(f('aabaaabaaabaaaba', 'b.*b') == 'baaabaaabaaab')
@@ -101,7 +101,7 @@ end
 assert(f1('alo alx 123 b\0o b\0o', '(..*) %1') == "b\0o b\0o")
 assert(f1('axz123= 4= 4 34', '(.+)=(.*)=%2 %1') == '3= 4= 4 3')
 assert(f1('=======', '^(=*)=%1$') == '=======')
-assert(string.match('==========', '^([=]*)=%1$') == nil)
+assert(not string.match('==========', '^([=]*)=%1$'))
 
 local function range (i, j)
   if i <= j then
@@ -135,7 +135,7 @@ print('+');
 assert(string.match("alo xyzK", "(%w+)K") == "xyz")
 assert(string.match("254 K", "(%d*)K") == "")
 assert(string.match("alo ", "(%w*)$") == "")
-assert(string.match("alo ", "(%w+)$") == nil)
+assert(not string.match("alo ", "(%w+)$"))
 assert(string.find("(álo)", "%(á") == 1)
 local a, b, c, d, e = string.match("âlo alo", "^(((.).).* (%w*))$")
 assert(a == 'âlo alo' and b == 'âl' and c == 'â' and d == 'alo' and e == nil)
@@ -209,7 +209,7 @@ assert(s == r and t[1] == 1 and t[3] == 3 and t[7] == 4 and t[13] == 4)
 
 
 function isbalanced (s)
-  return string.find(string.gsub(s, "%b()", ""), "[()]") == nil
+  return not string.find(string.gsub(s, "%b()", ""), "[()]")
 end
 
 assert(isbalanced("(9 ((8))(\0) 7) \0\0 a b ()(c)() a"))
diff --git a/testes/strings.lua b/testes/strings.lua
index 2e0e160f..97875ec0 100644
--- a/testes/strings.lua
+++ b/testes/strings.lua
@@ -56,13 +56,13 @@ a,b = string.find("123456789", "345")
 assert(string.sub("123456789", a, b) == "345")
 assert(string.find("1234567890123456789", "345", 3) == 3)
 assert(string.find("1234567890123456789", "345", 4) == 13)
-assert(string.find("1234567890123456789", "346", 4) == nil)
+assert(not string.find("1234567890123456789", "346", 4))
 assert(string.find("1234567890123456789", ".45", -9) == 13)
-assert(string.find("abcdefg", "\0", 5, 1) == nil)
+assert(not string.find("abcdefg", "\0", 5, 1))
 assert(string.find("", "") == 1)
 assert(string.find("", "", 1) == 1)
 assert(not string.find("", "", 2))
-assert(string.find('', 'aaa', 1) == nil)
+assert(not string.find('', 'aaa', 1))
 assert(('alo(.)alo'):find('(.)', 1, 1) == 4)
 
 assert(string.len("") == 0)
diff --git a/testes/utf8.lua b/testes/utf8.lua
index acbb181d..5954f6e8 100644
--- a/testes/utf8.lua
+++ b/testes/utf8.lua
@@ -30,8 +30,8 @@ local function checksyntax (s, t)
   assert(assert(load(ts))() == s)
 end
 
-assert(utf8.offset("alo", 5) == nil)
-assert(utf8.offset("alo", -4) == nil)
+assert(not utf8.offset("alo", 5))
+assert(not utf8.offset("alo", -4))
 
 -- 'check' makes several tests over the validity of string 's'.
 -- 't' is the list of codepoints of 's'.