Add check to -i short circuit for the automatic key

pkg/cmd/codespace/ssh.go

@@ -246,7 +246,11 @@ func useAutomaticSSHKeys(
 		arg := args[i]
 
 		if arg == "-i" {
-			// User specified the identity file so just trust it is correct
+			if i+1 < len(args) && path.Base(args[i+1]) == automaticPrivateKeyName {
+				return true, nil
+			}
+
+			// User specified a custom identity file so just trust it is correct
 			return false, nil
 		}
 
@@ -550,13 +554,11 @@ func (a *App) printOpenSSHConfig(ctx context.Context, opts sshOptions) (err erro
 		return fmt.Errorf("error formatting template: %w", err)
 	}
 
-	sshDir, err := config.HomeDirPath(".ssh")
+	automaticIdentityFilePath, err := automaticPrivateKeyPath()
 	if err != nil {
 		return fmt.Errorf("error finding .ssh directory: %w", err)
 	}
 
-	automaticIdentityFilePath := path.Join(sshDir, automaticPrivateKeyName)
-
 	ghExec := a.executable.Executable()
 	for result := range sshUsers {
 		if result.err != nil {
@@ -599,6 +601,15 @@ func (a *App) printOpenSSHConfig(ctx context.Context, opts sshOptions) (err erro
 	return status
 }
 
+func automaticPrivateKeyPath() (string, error) {
+	sshDir, err := config.HomeDirPath(".ssh")
+	if err != nil {
+		return "", err
+	}
+
+	return path.Join(sshDir, automaticPrivateKeyName), nil
+}
+
 type cpOptions struct {
 	sshOptions
 	recursive bool // -r

pkg/cmd/codespace/ssh_test.go

@@ -125,16 +125,33 @@ func TestAutomaticSSHKeyPairs(t *testing.T) {
 	}
 }
 
-func TestDontUseAutomaticSSHKeysWithCustomPrivateKey(t *testing.T) {
-	args := []string{"-i", "private-key"}
-	result, err := useAutomaticSSHKeys(context.Background(), ssh.Context{}, nil, args, sshOptions{})
-
-	if err != nil {
-		t.Errorf("Unexpected error from useAutomaticSSHKeys: %v", err)
+func TestUseAutomaticSSHKeysIdentityFileArg(t *testing.T) {
+	tests := []struct {
+		identityFileArg string
+		wantResult      bool
+	}{
+		{"custom-private-key", false},
+		{automaticPrivateKeyName, true},
+		{"", false}, // Edge case check for missing arg value
 	}
 
-	if result != false {
-		t.Errorf("Want useAutomaticSSHKeys to be false, got true")
+	for _, tt := range tests {
+		t.Logf("%v", tt.identityFileArg)
+
+		args := []string{"-i"}
+		if tt.identityFileArg != "" {
+			args = append(args, tt.identityFileArg)
+		}
+
+		result, err := useAutomaticSSHKeys(context.Background(), ssh.Context{}, nil, args, sshOptions{})
+
+		if err != nil {
+			t.Errorf("Unexpected error from useAutomaticSSHKeys: %v", err)
+		}
+
+		if result != tt.wantResult {
+			t.Errorf("Want useAutomaticSSHKeys to be %v, got %v", tt.wantResult, result)
+		}
 	}
 }