blueprint,disk: tiny style changes

This commit changes some ordering and var names, very minor, test
tweaks, c.f.
* osbuild#1041 (comment)
* osbuild#1041 (comment)
* osbuild#1041 (comment)
* osbuild#1041 (comment)
* osbuild#1041 (comment)
* osbuild#1041 (comment)
* osbuild#1041 (comment)
* osbuild#1041 (comment)

pkg/blueprint/disk_customizations.go

@@ -314,12 +314,12 @@ func (p *DiskCustomization) Validate() error {
 	var errs []error
 	for _, part := range p.Partitions {
 		switch part.Type {
+		case "plain", "":
+			errs = append(errs, part.validatePlain(mountpoints))
 		case "lvm":
 			errs = append(errs, part.validateLVM(mountpoints, vgnames))
 		case "btrfs":
 			errs = append(errs, part.validateBtrfs(mountpoints))
-		case "plain", "":
-			errs = append(errs, part.validatePlain(mountpoints))
 		default:
 			errs = append(errs, fmt.Errorf("unknown partition type: %s", part.Type))
 		}
@@ -382,19 +382,19 @@ func (p *DiskCustomization) ValidateLayoutConstraints() error {
 
 // Check that the fs type is valid for the mountpoint.
 func validateFilesystemType(path, fstype string) error {
-	badfsMsg := "unsupported filesystem type for %q: %s"
+	badfsMsgFmt := "unsupported filesystem type for %q: %s"
 	switch path {
 	case "/boot":
 		switch fstype {
 		case "xfs", "ext4":
 		default:
-			return fmt.Errorf(badfsMsg, path, fstype)
+			return fmt.Errorf(badfsMsgFmt, path, fstype)
 		}
 	case "/boot/efi":
 		switch fstype {
 		case "vfat":
 		default:
-			return fmt.Errorf(badfsMsg, path, fstype)
+			return fmt.Errorf(badfsMsgFmt, path, fstype)
 		}
 	}
 	return nil

pkg/blueprint/disk_customizations_test.go

@@ -848,12 +848,6 @@ func TestPartitioningLayoutConstraints(t *testing.T) {
 		"unhappy-btrfs+lvm": {
 			partitioning: &blueprint.DiskCustomization{
 				Partitions: []blueprint.PartitionCustomization{
-					{
-						Type: "ext4",
-						FilesystemTypedCustomization: blueprint.FilesystemTypedCustomization{
-							Mountpoint: "/data",
-						},
-					},
 					{
 						Type: "btrfs",
 						BtrfsVolumeCustomization: blueprint.BtrfsVolumeCustomization{
@@ -1276,12 +1270,6 @@ func TestPartitionCustomizationUnmarshalJSON(t *testing.T) {
 						"mountpoint": "/home",
 						"label": "home",
 						"fs_type": "ext4"
-					},
-					{
-						"name": "loglv",
-						"mountpoint": "/var/log",
-						"label": "log",
-						"fs_type": "xfs"
 					}
 				]
 			}`,

pkg/disk/partition_table.go

@@ -1000,17 +1000,17 @@ func EnsureRootFilesystem(pt *PartitionTable, defaultFsType FSType) error {
 // partition to the end of the existing partition table therefore it is best to
 // call this function early to put boot near the front (as is conventional).
 func AddBootPartition(pt *PartitionTable, bootFsType FSType) error {
+	if bootFsType == FS_NONE {
+		return fmt.Errorf("error creating boot partition: no filesystem type")
+	}
+
 	// collect all labels to avoid conflicts
 	labels := make(map[string]bool)
 	_ = pt.ForEachMountable(func(mnt Mountable, path []Entity) error {
 		labels[mnt.GetFSSpec().Label] = true
 		return nil
 	})
 
-	if bootFsType == FS_NONE {
-		return fmt.Errorf("error creating boot partition: no filesystem type")
-	}
-
 	bootLabel, err := genUniqueString("boot", labels)
 	if err != nil {
 		return fmt.Errorf("error creating boot partition: %w", err)
@@ -1158,12 +1158,8 @@ func (options *CustomPartitionTableOptions) getfstype(fstype string) (string, er
 // NewCustomPartitionTable creates a partition table based almost entirely on the disk customizations from a blueprint.
 func NewCustomPartitionTable(customizations *blueprint.DiskCustomization, options *CustomPartitionTableOptions, rng *rand.Rand) (*PartitionTable, error) {
 	if options == nil {
-		// init options with defaults
-		options = &CustomPartitionTableOptions{
-			PartitionTableType: PT_GPT,
-		}
+		options = &CustomPartitionTableOptions{}
 	}
-
 	if customizations == nil {
 		customizations = &blueprint.DiskCustomization{}
 	}
@@ -1255,7 +1251,7 @@ func addPlainPartition(pt *PartitionTable, partition blueprint.PartitionCustomiz
 	}
 	partType, err := getPartitionTypeIDfor(pt.Type, typeName)
 	if err != nil {
-		return fmt.Errorf("error creating root partition: %w", err)
+		return fmt.Errorf("error getting partition type ID for %q: %w", partition.Mountpoint, err)
 	}
 	newpart := Partition{
 		Type:     partType,
@@ -1275,7 +1271,7 @@ func addPlainPartition(pt *PartitionTable, partition blueprint.PartitionCustomiz
 func addLVMPartition(pt *PartitionTable, partition blueprint.PartitionCustomization, options *CustomPartitionTableOptions) error {
 	vgname := partition.Name
 	if vgname == "" {
-		// count existing volume groups and generate unique name
+		// get existing volume groups and generate unique name
 		existing := make(map[string]bool)
 		for _, part := range pt.Partitions {
 			vg, ok := part.Payload.(*LVMVolumeGroup)