integration/signing_test: move findFingerprint to utils_test.go

Prep for another test which will also use this.

Signed-off-by: Jonathan Lebon <jonathan@jlebon.com>

integration/signing_test.go

@@ -1,12 +1,9 @@
 package main
 
 import (
-	"bytes"
-	"errors"
 	"fmt"
 	"os"
 	"os/exec"
-	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -29,16 +26,6 @@ type signingSuite struct {
 
 var _ = suite.SetupAllSuite(&signingSuite{})
 
-func findFingerprint(lineBytes []byte) (string, error) {
-	for line := range bytes.SplitSeq(lineBytes, []byte{'\n'}) {
-		fields := strings.Split(string(line), ":")
-		if len(fields) >= 10 && fields[0] == "fpr" {
-			return fields[9], nil
-		}
-	}
-	return "", errors.New("No fingerprint found")
-}
-
 func (s *signingSuite) SetupSuite() {
 	t := s.T()
 	_, err := exec.LookPath(skopeoBinary)

integration/utils_test.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"compress/gzip"
 	"encoding/json"
+	"errors"
 	"io"
 	"net"
 	"net/netip"
@@ -29,6 +30,17 @@ var skopeoBinary = func() string {
 	return "skopeo"
 }()
 
+// findFingerprint extracts the GPG key fingerprint from gpg --with-colons output.
+func findFingerprint(lineBytes []byte) (string, error) {
+	for line := range bytes.SplitSeq(lineBytes, []byte{'\n'}) {
+		fields := strings.Split(string(line), ":")
+		if len(fields) >= 10 && fields[0] == "fpr" {
+			return fields[9], nil
+		}
+	}
+	return "", errors.New("No fingerprint found")
+}
+
 const (
 	testFQIN           = "docker://quay.io/libpod/busybox" // tag left off on purpose, some tests need to add a special one
 	testFQIN64         = "docker://quay.io/libpod/busybox:amd64"