build.lua: match long comments correctly; flush and close files properly; implement fs.copy() on top of lfs

build.lua

@@ -17,6 +17,28 @@ local fs = (function()
 	--if we're not in minecraft, implement the functions we need on top of LuaFileSystem
 	local lfs = require('lfs')
 	local fs = {}
+	function fs.copy(src, dst)
+		--lfs doesn't seem to have this? for small files we can just `cat <src >dst`
+		src, err = io.open(src, 'rb')
+		if not src then
+			return nil, err
+		end
+
+		dst, err = io.open(dst, 'wb')
+		if not dst then
+			src:close()
+			return nil, err
+		end
+
+		--outside of opencomputers, we more than likely have more than enough ram, so read everything in one shot
+		local ok; ok, err = src:read('a')
+		if ok then ok, err = dst:write(ok) end
+		if ok then ok, err = dst:flush() end
+
+		src:close()
+		dst:close()
+		return ok, err
+	end
 	function fs.list(path)
 		local entries = {}
 		for name in lfs.dir(path) do
@@ -84,7 +106,7 @@ local function exportFile(srcpath, dstpath)
 	local dstf = assert(io.open(dstpath, 'w'))
 
 	--for now, run a very minimal minifier
-	local longEnd --nil normally, some "]==]--" string if we're in a long comment
+	local longEnd --nil normally, some "]==]" string if we're in a long comment
 
 	for line in srcf:lines() do
 		::stripComments:: --strip comments, including weird ones like "--[[ ]]-- --[=[ ]=]-- --text" all in one line
@@ -108,8 +130,8 @@ local function exportFile(srcpath, dstpath)
 		end
 		if line:byte(comment+2) == string.byte('[') then --start of a long comment
 			local depth = #line:sub(comment+2):match('^%[(%=*)%[') --validating syntax earlier ensures this will match
-			longEnd = string.format(']%s]--', string.rep('=', depth))
-			line = line:sub(comment + 4 + depth) -- #'--[' + depth + #'['
+			longEnd = string.format(']%s]', string.rep('=', depth))
+			line = line:sub(comment + 4 + depth) --len('--[') + depth + len('[')
 			goto stripComments --start from the beginning in case the comment ends on the same line it starts on
 		else
 			--found a short comment, remove to end of line
@@ -121,12 +143,16 @@ local function exportFile(srcpath, dstpath)
 		assert(not longEnd, 'shouldn\'t emit anything in a long comment')
 		line = assert(line:match('^%s*(.-)%s*$')) --strip leading and trailing whitespace
 		if #line > 0 then
-			dstf:write(line, '\n')
+			assert(dstf:write(line, '\n'))
 		end
 
 		::nextLine::
 	end
 	assert(not longEnd, 'unclosed long comment')
+
+	assert(dstf:flush())
+	dstf:close()
+	srcf:close()
 end
 
 fs.makeDirectory(outdir)