### Timer changes

Go 1.23 makes two significant changes to the implementation of
[time.Timer] and [time.Ticker].

First, `Timer`s and `Ticker`s that are no longer referred to by the program
become eligible for garbage collection immediately, even if their
`Stop` methods have not been called.
Earlier versions of Go did not collect unstopped `Timer`s until after
they had fired and never collected unstopped `Ticker`s.

//go:build !(windows || js || wasip1)

package main

import (
	"regexp"
	"strings"
	"testing"
)

func TestExitCodeFilter(t *testing.T) {
	// Write text to the filter one character at a time.
	var out strings.Builder
	f, exitStr := newExitCodeFilter(&out)
	// Embed a "fake" exit code in the middle to check that we don't get caught on it.
	pre := "abc" + exitStr + "123def"
	text := pre + exitStr + `1`