Vv's Programs

PVar["variableName"]="value"	OR	PVar.variableName="value"

print (PVar["variableName])   OR   print(PVar.variableName)

-- ================================================
-- Persistent variables
-- ================================================

PVar={_PVarPath="/vvSystem/"}
setmetatable(PVar,PVar)

PVar._getVariablePath=function(name)
	local filepath = fs.combine(PVar["_PVarPath"],name..".var")
	if not fs.exists(PVar["_PVarPath"]) then
		fs.makeDir(PVar["_PVarPath"])
	end
	return filepath
end

function PVar._assertOnInvalidName(name)  
	if name:sub(1,1)=="_" then
		error("Variable names cannot start with _")
	else
		local invalidCharPos,_ = name:find("[:/*|<>;%s]")
		if invalidCharPos then
			error("Variable names contains invalid character '"..name:sub(invalidCharPos,invalidCharPos).."'")
		end
	end
end

function PVar.__index(tbl,name)
	PVar._assertOnInvalidName(name)
	local f = io.open(PVar._getVariablePath(name), "r")
	if f then
		local content = textutils.unserialize(f:read())
		f:close()
		return content
	else
		return nil
	end
end

function PVar.__newindex(tbl,name,value)
	PVar._assertOnInvalidName(name)
	if value then	  
		local f = io.open(PVar._getVariablePath(name), "w")	
		assert(f,"FAIL: could not open file")
		if f then
			f:write(textutils.serialize(value))
			f:close()
		end
	else
		fs.delete(PVar._getVariablePath(name))
	end
end

-- ================================================
-- Test cases
-- ================================================

_doTestCases=false

if (_doTestCases) then
	local function nz(v) if v then return v else return "nil" end end

	PVar["t"]="test"

	assert(PVar["doesnotexist"]==nil,"FAIL: expected nul for nonexisting variable")
	assert(PVar["t"]=="test","FAIL: Expected 'test' but got:"..nz(PVar["t"]))
	assert(fs.exists(PVar["_PVarPath"].."t.txt"),"FAIL: file expected to exist")
	PVar["t"]=nul
	assert(PVar["t"]==nul,"FAIL: deleted variable should return nul")
	assert(not fs.exists(PVar["_PVarPath"].."t.txt"),"FAIL: file should be deleted")
	PVar["t"]=6
	assert(type(PVar["t"])=="number","FAIL: returned wrong type")
	print("Test case completed OK")
end

Assert={}

function Assert.hasError(funcWithParams, arg1, arg2)
	local status,err = pcall(unpack(funcWithParams))
	if status or (arg2 and arg1~=err:sub(err:find("%s")+1)) then
		if arg2  then
			error(arg2)
		elseif arg1 then
			error(arg1)
		else
			error("expected error did not trigger")
		end
	end
end

function Assert.hasNoError(funcWithParams, optionalMessage)
	local status,err = pcall(unpack(funcWithParams))

	if not status then
		if optionalMessage  then
			error(optionalMessage)
		else
			error("expected no error but got: " .. err)
		end
	end
end

-- =================================================

_doTestCases=false

if (_doTestCases) then
	-- =[hasError]=
	Assert.hasError({function() error("test") end},"test", "FAILED: Expected error (1)")
	Assert.hasError({function() error("test") end},"FAILED: Expected error (2)")
	Assert.hasError({function() error("test") end})
	assert(not pcall(Assert.hasError, {function() end}),"FAILED: hasError(4): assert should not trigger when no error has detected")
	-- =[hasNoError]=
	Assert.hasNoError({function() end},"FAILED: HasNoError(1): Expected no errors")
	assert(not pcall(Assert.hasNoError, {function() error("test") end} ,"dummy"),"FAILED: HasNoError(2): hasNoError should have failed, but succeeded")
	assert(not pcall(Assert.hasNoError, {function() error("someError") end}),"FAILED: HasNoError(3): hasNoError should have failed, but succeeded")
	-- = ALL DONE
	print("TestCases OK")
end