tests: add tests for `cli-plugins/socket`

Signed-off-by: Laura Brehm <laurabrehm@hey.com>

cli-plugins/socket/socket_test.go

@@ -0,0 +1,129 @@
+package socket
+
+import (
+	"io/fs"
+	"net"
+	"os"
+	"runtime"
+	"testing"
+	"time"
+
+	"gotest.tools/v3/assert"
+	"gotest.tools/v3/poll"
+)
+
+func TestSetupConn(t *testing.T) {
+	t.Run("updates conn when connected", func(t *testing.T) {
+		var conn *net.UnixConn
+		listener, err := SetupConn(&conn)
+		assert.NilError(t, err)
+		assert.Check(t, listener != nil, "returned nil listener but no error")
+		addr, err := net.ResolveUnixAddr("unix", listener.Addr().String())
+		assert.NilError(t, err, "failed to resolve listener address")
+
+		_, err = net.DialUnix("unix", nil, addr)
+		assert.NilError(t, err, "failed to dial returned listener")
+
+		pollConnNotNil(t, &conn)
+	})
+
+	t.Run("allows reconnects", func(t *testing.T) {
+		var conn *net.UnixConn
+		listener, err := SetupConn(&conn)
+		assert.NilError(t, err)
+		assert.Check(t, listener != nil, "returned nil listener but no error")
+		addr, err := net.ResolveUnixAddr("unix", listener.Addr().String())
+		assert.NilError(t, err, "failed to resolve listener address")
+
+		otherConn, err := net.DialUnix("unix", nil, addr)
+		assert.NilError(t, err, "failed to dial returned listener")
+
+		otherConn.Close()
+
+		_, err = net.DialUnix("unix", nil, addr)
+		assert.NilError(t, err, "failed to redial listener")
+	})
+
+	t.Run("does not leak sockets to local directory", func(t *testing.T) {
+		var conn *net.UnixConn
+		listener, err := SetupConn(&conn)
+		assert.NilError(t, err)
+		assert.Check(t, listener != nil, "returned nil listener but no error")
+		checkDirClean(t)
+
+		addr, err := net.ResolveUnixAddr("unix", listener.Addr().String())
+		assert.NilError(t, err, "failed to resolve listener address")
+		_, err = net.DialUnix("unix", nil, addr)
+		assert.NilError(t, err, "failed to dial returned listener")
+		checkDirClean(t)
+	})
+}
+
+func checkDirClean(t *testing.T) {
+	t.Helper()
+
+	files, err := os.ReadDir(".")
+	assert.NilError(t, err, "failed to list files in dir to check for leaked sockets")
+
+	for _, f := range files {
+		info, err := f.Info()
+		assert.NilError(t, err, "failed to check file info")
+		if info.Mode().Type() == fs.ModeSocket {
+			t.Fatal("found socket in a local directory")
+		}
+	}
+}
+
+func TestConnectAndWait(t *testing.T) {
+	t.Run("calls cancel func on EOF", func(t *testing.T) {
+		var conn *net.UnixConn
+		listener, err := SetupConn(&conn)
+		assert.NilError(t, err, "failed to setup listener")
+
+		done := make(chan struct{})
+		t.Setenv(EnvKey, listener.Addr().String())
+		cancelFunc := func() {
+			done <- struct{}{}
+		}
+		ConnectAndWait(cancelFunc)
+		pollConnNotNil(t, &conn)
+		conn.Close()
+
+		select {
+		case <-done:
+		case <-time.After(10 * time.Millisecond):
+			t.Fatal("cancel function not closed after 10ms")
+		}
+	})
+
+	t.Run("connect goroutine exits after EOF", func(t *testing.T) {
+		var conn *net.UnixConn
+		listener, err := SetupConn(&conn)
+		assert.NilError(t, err, "failed to setup listener")
+		t.Setenv(EnvKey, listener.Addr().String())
+		numGoroutines := runtime.NumGoroutine()
+
+		ConnectAndWait(func() {})
+		assert.Equal(t, runtime.NumGoroutine(), numGoroutines+1)
+
+		pollConnNotNil(t, &conn)
+		conn.Close()
+		poll.WaitOn(t, func(t poll.LogT) poll.Result {
+			if runtime.NumGoroutine() > numGoroutines+1 {
+				return poll.Continue("waiting for connect goroutine to exit")
+			}
+			return poll.Success()
+		}, poll.WithDelay(1*time.Millisecond), poll.WithTimeout(10*time.Millisecond))
+	})
+}
+
+func pollConnNotNil(t *testing.T, conn **net.UnixConn) {
+	t.Helper()
+
+	poll.WaitOn(t, func(t poll.LogT) poll.Result {
+		if *conn == nil {
+			return poll.Continue("waiting for conn to not be nil")
+		}
+		return poll.Success()
+	}, poll.WithDelay(1*time.Millisecond), poll.WithTimeout(10*time.Millisecond))
+}