Hey I've been testing

SystemOutput

(https://docs.lucee.org/reference/functions/systemoutput.html) to write to stdout and stderr. Seems to be working well. I was hoping to write an test for the code, so wanted to listen to stdout and stderr as part of that. Anyone done this? I looked on S/O for a Java approach to it, and thusfar the answers have all been along the lines of "ooooh... that isn't easy, so do it this other way instead". The other ways are not helpful to me in this case (although it's good knowledge to know).

you know it also can dump non simple values?

@Adam Cameron You can wrap the Java's

System.out

print reader, but it's certainly a pain

Cheers for that fella. I had read about the PrintStream stuff this afternoon, but thought it might be stretching my Java a bit and decided to try other options first. BUT you piqued my interest mentioning it again, so I tried my hand. What do you make of this (gist here: https://gist.github.com/adamcameron/8b0913963c768b089b48434f43d5eaac):

import test.BaseSpec

component extends=BaseSpec {

	function run() {
		describe("Trying to capture stdout", () => {

			var fixtures = {}

			aroundEach((spec) => {
				try {
					fixtures.outFilePath = getTempDirectory() & createUuid() & ".out"
					fixtures.system = createObject("java", "java.lang.System")

					var originalOut = fixtures.system.out
					var fos = createObject("java", "java.io.FileOutputStream").init(fixtures.outFilePath)
					var ps = createObject("java", "java.io.PrintStream").init(fos, true)

					fixtures.system.setOut(ps)

					spec.body()
				} finally {
					fixtures.system.setOut(originalOut)
				}
			})

			it("captures stuff Java puts there", () => {
				var testString = "find this (Java)"
				fixtures.system.out.println(testString)

				var contents = fileRead(fixtures.outFilePath)
				expect(contents).toBe(testString & chr(10))
			})

			it("doesn't capture stuff Lucee puts there", () => {
				systemOutput("find this (Lucee)")

				var contents = fileRead(fixtures.outFilePath)

				expect(contents).toBeEmpty() // except I wish this *wasn't* the case
			})
		})
	}
}

@Adam Cameron What you're doing is fine, but the issue is (at least from me flipping through code for the past 3 minutes) that Lucee's

systemOutput()

function doesn't just internally do this

System.out.println( yourText )

Instead, it does this

PrintStream stream = CFMLEngineImpl.CONSOLE_OUT;
		stream.println(string);

And that

CONSOLE_OUT

is a static variable set when the CFMLEngine is constructed like so

public static final PrintStream CONSOLE_ERR = System.err;
	public static final PrintStream CONSOLE_OUT = System.out;

This means Lucee is going to print your string to whatever the print stream WAS back when Lucee started. Which, for the sake of discussion is a wrapper, but that's mostly beside the point. What Micha never considered was the possibility that someone would try to do their own swap in CFML at runtime.

Yeah I figured it was something along those lines.

Now, on a totally unrelated note-- you can also avoid the entire file writing bit by just using a

ByteArrayOutputStream

instead of a file ouput stream. It will buffer the input internally and you can just grab its contents when your test is done.

AH

you'd use

BAOS.toString( "UTF-8" )

to get the bytes back out as a string

I as hoping to grab it from the stream direct, but didn't find one I could read back from. Thanks!

I love Java's input/output stream/reader classes, but they're a sea of options....

Well... you know... Java. Needs to be able to do... everything.