Added support for using stin/stdout as input/output.

Author: ReFreezed

.gitignore

@@ -4,6 +4,8 @@ local/
 /*.sublime-*
 /.run
 
+/temp/
+
 /tests/quickTest.lua
 /tests/quickTest.meta.lua
 

preprocess-cl.lua

@@ -21,6 +21,8 @@ exec lua "$0" "$@"
 		OR
 		lua preprocess-cl.lua --outputpaths [options] [--] inputpath1 outputpath1 [inputpath2 outputpath2 ...]
 
+		File paths can be "-" for usage of stdin/stdout.
+
 	Examples:
 		lua preprocess-cl.lua --saveinfo=logs/info.lua --silent src/main.lua2p src/network.lua2p
 		lua preprocess-cl.lua --debug src/main.lua2p src/network.lua2p
@@ -97,16 +99,17 @@ exec lua "$0" "$@"
 			to see what information is saved.
 
 		--silent
-			Only print errors to the console.
+			Only print errors to the console. (This flag is automatically
+			enabled if an output path is stdout.)
 
 		--debug
 			Enable some preprocessing debug features. Useful if you want
 			to inspect the generated metaprogram (*.meta.lua). (This also
 			enables the --meta option.)
 
 		--
-			Stop options from being parsed further. Needed if you have
-			paths starting with "-".
+			Stop options from being parsed further. Needed if you have paths
+			starting with "-" (except for usage of stdin/stdout).
 
 ----------------------------------------------------------------
 
@@ -157,7 +160,7 @@ local args = arg
 
 local major, minor = _VERSION:match"Lua (%d+)%.(%d+)"
 if not major then
-	io.stderr:write("[LuaPreprocess] Warning: Could not detect Lua version.\n") -- Note: This line does not obey the --silent option.
+	io.stderr:write("[LuaPreprocess] Warning: Could not detect Lua version.\n")
 else
 	major = tonumber(major)
 	minor = tonumber(minor)
@@ -269,10 +272,14 @@ local pathsIn            = {}
 local pathsOut           = {}
 
 for _, arg in ipairs(args) do
-	if not (processOptions and arg:find"^%-") then
-		local paths = (hasOutputPaths and #pathsOut < #pathsIn and pathsOut or pathsIn)
+	if not (processOptions and arg:find"^%-.") then
+		local paths = (hasOutputPaths and #pathsOut < #pathsIn) and pathsOut or pathsIn
 		table.insert(paths, arg)
 
+		if arg == "-" and (not hasOutputPaths or paths == pathsOut) then
+			silent = true
+		end
+
 	elseif arg == "--" then
 		processOptions = false
 
@@ -432,7 +439,7 @@ sendMessage("init", pathsIn, (hasOutputPaths and pathsOut or nil))
 
 if not hasOutputPaths then
 	for i, pathIn in ipairs(pathsIn) do
-		pathsOut[i] = pathIn:gsub("%.%w+$", "").."."..outputExtension
+		pathsOut[i] = (pathIn == "-") and "-" or pathIn:gsub("%.%w+$", "").."."..outputExtension
 	end
 end
 
@@ -444,13 +451,16 @@ end
 
 local pathsSetIn  = {}
 local pathsSetOut = {}
+
 for i = 1, #pathsIn do
 	if pathsSetIn [pathsIn [i]] then  errorLine("Duplicate input path: " ..pathsIn [i])  end
 	if pathsSetOut[pathsOut[i]] then  errorLine("Duplicate output path: "..pathsOut[i])  end
+
 	pathsSetIn [pathsIn [i]] = true
 	pathsSetOut[pathsOut[i]] = true
-	if pathsSetOut[pathsIn [i]] then  errorLine("Path is both input and output: "..pathsIn [i])  end
-	if pathsSetIn [pathsOut[i]] then  errorLine("Path is both input and output: "..pathsOut[i])  end
+
+	if pathsIn [i] ~= "-" and pathsSetOut[pathsIn [i]] then  errorLine("Path is both input and output: "..pathsIn [i])  end
+	if pathsOut[i] ~= "-" and pathsSetIn [pathsOut[i]] then  errorLine("Path is both input and output: "..pathsOut[i])  end
 end
 
 
@@ -475,7 +485,7 @@ for i, pathIn in ipairs(pathsIn) do
 	local pathOut  = pathsOut[i]
 	local pathMeta = pathOut:gsub("%.%w+$", "")..".meta.lua"
 
-	if not outputMeta then
+	if not outputMeta or pathOut == "-" then
 		pathMeta = nil
 	end
 
@@ -582,10 +592,10 @@ end
 printfNoise(
 	"All done! (%.3fs, %.0f file%s, %.0f LOC, %.0f line%s, %.0f token%s, %s)",
 	os.clock()-startClock,
-	#pathsIn,   #pathsIn   == 1 and "" or "s",
+	#pathsIn,   (#pathsIn   == 1) and "" or "s",
 	lineCountCode,
-	lineCount,  lineCount  == 1 and "" or "s",
-	tokenCount, tokenCount == 1 and "" or "s",
+	lineCount,  (lineCount  == 1) and "" or "s",
+	tokenCount, (tokenCount == 1) and "" or "s",
 	formatBytes(byteCount)
 )
 

preprocess.lua

@@ -251,7 +251,7 @@ end
 
 
 function printf(s, ...)
-	print(s:format(...))
+	print(F(s, ...))
 end
 
 -- printTokens( tokens [, filterUselessTokens ] )
@@ -764,7 +764,7 @@ function _tokenize(s, path, allowPpTokens, allowBacktickStrings, allowJitSyntax)
 		tok.lineEnd = ln
 
 		tableInsert(tokens, tok)
-		-- print(#tokens, tok.type, tok.representation)
+		-- print(#tokens, tok.type, tok.representation) -- DEBUG
 	end
 
 	return tokens
@@ -1334,7 +1334,7 @@ local metaFuncs = {}
 
 -- printf()
 --   printf( format, value1, ... )
---   Print a formatted string.
+--   Print a formatted string to stdout.
 metaFuncs.printf = printf
 
 -- getFileContents()
@@ -2616,7 +2616,9 @@ local function _processFileOrString(params, isFile)
 		if not params.pathIn  then  error("Missing 'pathIn' in params.",  2)  end
 		if not params.pathOut then  error("Missing 'pathOut' in params.", 2)  end
 
-		if params.pathOut == params.pathIn then  error("'pathIn' and 'pathOut' are the same in params.", 2)  end
+		if params.pathOut == params.pathIn and params.pathOut ~= "-" then
+			error("'pathIn' and 'pathOut' are the same in params.", 2)
+		end
 
 	else
 		if not params.code then  error("Missing 'code' in params.", 2)  end
@@ -2625,10 +2627,14 @@ local function _processFileOrString(params, isFile)
 	local luaUnprocessed, pathIn
 
 	if isFile then
+		pathIn = params.pathIn
 		local err
 
-		pathIn              = params.pathIn
-		luaUnprocessed, err = getFileContents(pathIn, true)
+		if pathIn == "-" then
+			luaUnprocessed, err = io.stdin:read"*a"
+		else
+			luaUnprocessed, err = getFileContents(pathIn, true)
+		end
 
 		if not luaUnprocessed then
 			errorf("Could not read file '%s'. (%s)", pathIn, err)
@@ -2650,7 +2656,7 @@ local function _processFileOrString(params, isFile)
 	end
 
 	local tokens = _tokenize(luaUnprocessed, pathIn, true, params.backtickStrings, params.jitSyntax)
-	-- printTokens(tokens)
+	-- printTokens(tokens) -- DEBUG
 
 	-- Info variables.
 	local lastTok = tokens[#tokens]
@@ -3029,7 +3035,7 @@ local function _processFileOrString(params, isFile)
 	--==============================================================
 
 	local luaMeta = table.concat(metaParts)
-	--[[ :PrintCode
+	--[[ DEBUG :PrintCode
 	print("=META===============================")
 	print(luaMeta)
 	print("====================================")
@@ -3068,7 +3074,7 @@ local function _processFileOrString(params, isFile)
 	end
 
 	local lua = table.concat(outputFromMeta)
-	--[[ :PrintCode
+	--[[ DEBUG :PrintCode
 	print("=OUTPUT=============================")
 	print(lua)
 	print("====================================")
@@ -3095,10 +3101,15 @@ local function _processFileOrString(params, isFile)
 	local pathOut = isFile and params.pathOut or "<output>"
 
 	if isFile then
-		local file = assert(io.open(pathOut, "wb"))
-		file:write(specialFirstLine or "")
-		file:write(lua)
-		file:close()
+		if pathOut == "-" then
+			io.stdout:write(specialFirstLine or "")
+			io.stdout:write(lua)
+		else
+			local file = assert(io.open(pathOut, "wb"))
+			file:write(specialFirstLine or "")
+			file:write(lua)
+			file:close()
+		end
 	end
 
 	-- Check if the output is valid Lua.
@@ -3218,8 +3229,8 @@ local pp = {
 	-- info: Table with various information. (See 'ProcessInfo' for more info.)
 	--
 	-- params: Table with these fields:
-	--   pathIn          = pathToInputFile       -- [Required]
-	--   pathOut         = pathToOutputFile      -- [Required]
+	--   pathIn          = pathToInputFile       -- [Required] Specify "-" to use stdin.
+	--   pathOut         = pathToOutputFile      -- [Required] Specify "-" to use stdout. (Note that if stdout is used then anything you print() in the metaprogram will end up there.)
 	--   pathMeta        = pathForMetaprogram    -- [Optional] You can inspect this temporary output file if an error occurs in the metaprogram.
 	--
 	--   debug           = boolean               -- [Optional] Debug mode. The metaprogram file is formatted more nicely and does not get deleted automatically.

tests/runQuickTestUsingStd.cmd

@@ -0,0 +1,13 @@
+@ECHO OFF
+CD /D "%~dp0.."
+
+IF NOT EXIST temp             MD  temp
+IF EXIST     temp\stdout.txt  DEL temp\stdout.txt
+IF EXIST     temp\stderr.txt  DEL temp\stderr.txt
+
+lua ./preprocess-cl.lua --debug --data="Hello, world!" - <tests\quickTest.lua2p 1>temp\stdout.txt 2>temp\stderr.txt
+REM lua ./preprocess-cl.lua --debug --data="Hello, world!" - --backtickstrings <tests\quickTest.lua2p 1>temp\stdout.txt 2>temp\stderr.txt
+REM lua ./preprocess-cl.lua --debug --data="Hello, world!" - --linenumbers <tests\quickTest.lua2p 1>temp\stdout.txt 2>temp\stderr.txt
+
+REM lua ./preprocess-cl.lua --debug --data="Hello, world!" --outputpaths - - <tests\quickTest.lua2p 1>temp\stdout.txt 2>temp\stderr.txt
+REM lua ./preprocess-cl.lua --debug --data="Hello, world!" --outputpaths - - --linenumbers <tests\quickTest.lua2p 1>temp\stdout.txt 2>temp\stderr.txt