refactor: the resolv.conf tests read through one helper

Co-Authored-By: Claude <noreply@anthropic.com>
Signed-off-by: karo <karolin.kostial@gmail.com>

Author: The127

internal/builder/resolving_test.go

@@ -14,55 +14,49 @@ import (
 
 func TestAHostWithAnIPv4NameserverResolvesOverIPv4(t *testing.T) {
 	// act
-	resolving, err := builder.HostResolving(strings.NewReader("nameserver 127.0.0.53\n"))
+	resolving := resolvingOf(t, "nameserver 127.0.0.53\n")
 
 	// assert
-	require.NoError(t, err)
 	assert.Equal(t, builder.Resolving{IPv4: true}, resolving)
 }
 
 func TestAHostWithAnIPv6NameserverResolvesOverIPv6(t *testing.T) {
 	// act
-	resolving, err := builder.HostResolving(strings.NewReader("nameserver ::1\n"))
+	resolving := resolvingOf(t, "nameserver ::1\n")
 
 	// assert
-	require.NoError(t, err)
 	assert.Equal(t, builder.Resolving{IPv6: true}, resolving)
 }
 
 func TestANameserverNamedWithAnInterfaceCountsAsItsAddress(t *testing.T) {
 	// act
-	resolving, err := builder.HostResolving(strings.NewReader("nameserver 192.168.1.1%eth0\n"))
+	resolving := resolvingOf(t, "nameserver 192.168.1.1%eth0\n")
 
 	// assert
-	require.NoError(t, err)
 	assert.Equal(t, builder.Resolving{IPv4: true}, resolving)
 }
 
 func TestANameserverAfterATabCounts(t *testing.T) {
 	// act
-	resolving, err := builder.HostResolving(strings.NewReader("nameserver\t1.1.1.1\n"))
+	resolving := resolvingOf(t, "nameserver\t1.1.1.1\n")
 
 	// assert
-	require.NoError(t, err)
 	assert.Equal(t, builder.Resolving{IPv4: true}, resolving)
 }
 
 func TestWhatFollowsTheNameserversAddressIsIgnored(t *testing.T) {
 	// act
-	resolving, err := builder.HostResolving(strings.NewReader("nameserver 1.1.1.1 # home router\n"))
+	resolving := resolvingOf(t, "nameserver 1.1.1.1 # home router\n")
 
 	// assert
-	require.NoError(t, err)
 	assert.Equal(t, builder.Resolving{IPv4: true}, resolving)
 }
 
 func TestTheNameserversAddressEndsAtATab(t *testing.T) {
 	// act
-	resolving, err := builder.HostResolving(strings.NewReader("nameserver 1.1.1.1\t# home router\n"))
+	resolving := resolvingOf(t, "nameserver 1.1.1.1\t# home router\n")
 
 	// assert
-	require.NoError(t, err)
 	assert.Equal(t, builder.Resolving{IPv4: true}, resolving)
 }
 
@@ -79,12 +73,21 @@ func TestAResolvConfThatCannotBeReadFails(t *testing.T) {
 
 func TestAHostThatNamesNoNameserverResolvesInNeitherFamily(t *testing.T) {
 	// act
-	resolving, err := builder.HostResolving(strings.NewReader("search example.com\noptions edns0\n"))
+	resolving := resolvingOf(t, "search example.com\noptions edns0\n")
 
 	// assert
-	require.NoError(t, err)
 	// libslirp from 4.8 on falls back to 127.0.0.1 and ::1 here, before it
 	// to nothing, and miso cannot tell which one QEMU runs with. A lookup
 	// that fails at once beats one that waits for a timeout
 	assert.Equal(t, builder.Resolving{}, resolving)
 }
+
+// resolvingOf is what a host with the resolv.conf given resolves in.
+func resolvingOf(t *testing.T, conf string) builder.Resolving {
+	t.Helper()
+
+	resolving, err := builder.HostResolving(strings.NewReader(conf))
+	require.NoError(t, err)
+
+	return resolving
+}