Merge branch 'lukeshu/lint'

4 files changed, 40 insertions, 32 deletions

diff --git a/lib/btrfs/btrfstree/btree.go b/lib/btrfs/btrfstree/btree.go
index 4c10ffa..89d4f9d 100644
--- a/lib/btrfs/btrfstree/btree.go
+++ b/lib/btrfs/btrfstree/btree.go
@@ -2,6 +2,8 @@
 //
 // SPDX-License-Identifier: GPL-2.0-or-later
 
+// Package btrfstree contains core b+-tree implementation and
+// interfaces.
 package btrfstree
 
 import (
diff --git a/lib/btrfs/btrfstree/btree_tree.go b/lib/btrfs/btrfstree/btree_tree.go
index df58c0c..1e3c789 100644
--- a/lib/btrfs/btrfstree/btree_tree.go
+++ b/lib/btrfs/btrfstree/btree_tree.go
@@ -188,7 +188,8 @@ func (fs TreeOperatorImpl) treeSearch(treeRoot TreeRoot, fn func(btrfsprim.Key,
 			return nil, nil, err
 		}
 
-		if node.Data.Head.Level > 0 {
+		switch {
+		case node.Data.Head.Level > 0:
 			// interior node
 
 			// Search for the right-most node.Data.BodyInterior item for which
@@ -220,7 +221,7 @@ func (fs TreeOperatorImpl) treeSearch(treeRoot TreeRoot, fn func(btrfsprim.Key,
 				ToMaxKey:         toMaxKey,
 			})
 			FreeNodeRef(node)
-		} else {
+		default:
 			// leaf node
 
 			// Search for a member of node.Data.BodyLeaf for which
diff --git a/lib/btrfs/btrfstree/path.go b/lib/btrfs/btrfstree/path.go
index 9b1a5c7..b9ab5bc 100644
--- a/lib/btrfs/btrfstree/path.go
+++ b/lib/btrfs/btrfstree/path.go
@@ -101,23 +101,22 @@ func (elem TreePathElem) writeNodeTo(w io.Writer) {
 func (path TreePath) String() string {
 	if len(path) == 0 {
 		return "(empty-path)"
+	}
+	var ret strings.Builder
+	fmt.Fprintf(&ret, "%s->", path[0].FromTree.Format(btrfsprim.ROOT_TREE_OBJECTID))
+	if len(path) == 1 && path[0] == (TreePathElem{FromTree: path[0].FromTree, FromItemSlot: -1}) {
+		ret.WriteString("(empty-path)")
 	} else {
-		var ret strings.Builder
-		fmt.Fprintf(&ret, "%s->", path[0].FromTree.Format(btrfsprim.ROOT_TREE_OBJECTID))
-		if len(path) == 1 && path[0] == (TreePathElem{FromTree: path[0].FromTree, FromItemSlot: -1}) {
-			ret.WriteString("(empty-path)")
-		} else {
-			path[0].writeNodeTo(&ret)
-		}
-		for _, elem := range path[1:] {
-			fmt.Fprintf(&ret, "[%v]", elem.FromItemSlot)
-			if elem.ToNodeAddr != 0 {
-				ret.WriteString("->")
-				elem.writeNodeTo(&ret)
-			}
+		path[0].writeNodeTo(&ret)
+	}
+	for _, elem := range path[1:] {
+		fmt.Fprintf(&ret, "[%v]", elem.FromItemSlot)
+		if elem.ToNodeAddr != 0 {
+			ret.WriteString("->")
+			elem.writeNodeTo(&ret)
 		}
-		return ret.String()
 	}
+	return ret.String()
 }
 
 func (path TreePath) DeepCopy() TreePath {
@@ -128,9 +127,10 @@ func (path TreePath) Parent() TreePath {
 	return path[:len(path)-1]
 }
 
-// path.Node(x) is like &path[x], but negative values of x move down
-// from the end of path (similar to how lists work in many other
-// languages, such as Python).
+// Node is returns an element from the path; `path.Node(x)` is like
+// `&path[x]`, but negative values of x move down from the end of path
+// (similar to how lists work in many other languages, such as
+// Python).
 func (path TreePath) Node(x int) *TreePathElem {
 	if x < 0 {
 		x += len(path)
diff --git a/lib/btrfs/btrfstree/types_node.go b/lib/btrfs/btrfstree/types_node.go
index 150539d..8295ccb 100644
--- a/lib/btrfs/btrfstree/types_node.go
+++ b/lib/btrfs/btrfstree/types_node.go
@@ -113,20 +113,22 @@ type NodeHeader struct {
 // .Head.NumItems.
 func (node Node) MaxItems() uint32 {
 	bodyBytes := node.Size - uint32(nodeHeaderSize)
-	if node.Head.Level > 0 {
+	switch {
+	case node.Head.Level > 0:
 		return bodyBytes / uint32(keyPointerSize)
-	} else {
+	default:
 		return bodyBytes / uint32(itemHeaderSize)
 	}
 }
 
 func (node Node) MinItem() (btrfsprim.Key, bool) {
-	if node.Head.Level > 0 {
+	switch {
+	case node.Head.Level > 0:
 		if len(node.BodyInterior) == 0 {
 			return btrfsprim.Key{}, false
 		}
 		return node.BodyInterior[0].Key, true
-	} else {
+	default:
 		if len(node.BodyLeaf) == 0 {
 			return btrfsprim.Key{}, false
 		}
@@ -135,12 +137,13 @@ func (node Node) MinItem() (btrfsprim.Key, bool) {
 }
 
 func (node Node) MaxItem() (btrfsprim.Key, bool) {
-	if node.Head.Level > 0 {
+	switch {
+	case node.Head.Level > 0:
 		if len(node.BodyInterior) == 0 {
 			return btrfsprim.Key{}, false
 		}
 		return node.BodyInterior[len(node.BodyInterior)-1].Key, true
-	} else {
+	default:
 		if len(node.BodyLeaf) == 0 {
 			return btrfsprim.Key{}, false
 		}
@@ -221,15 +224,15 @@ func (node Node) MarshalBinary() ([]byte, error) {
 
 	buf := make([]byte, node.Size)
 
-	if bs, err := binstruct.Marshal(node.Head); err != nil {
+	bs, err := binstruct.Marshal(node.Head)
+	if err != nil {
 		return buf, err
-	} else {
-		if len(bs) != nodeHeaderSize {
-			return nil, fmt.Errorf("header is %v bytes but expected %v",
-				len(bs), nodeHeaderSize)
-		}
-		copy(buf, bs)
 	}
+	if len(bs) != nodeHeaderSize {
+		return nil, fmt.Errorf("header is %v bytes but expected %v",
+			len(bs), nodeHeaderSize)
+	}
+	copy(buf, bs)
 
 	if node.Head.Level > 0 {
 		if err := node.marshalInteriorTo(buf[nodeHeaderSize:]); err != nil {
@@ -456,6 +459,8 @@ func newNodeRef[Addr ~int64]() *diskio.Ref[Addr, Node] {
 	return (*diskio.Ref[Addr, Node])(unsafe.Pointer(ret)) //nolint:gosec // I know it's unsafe.
 }
 
+// ReadNode reads a node from the given file.
+//
 // It is possible that both a non-nil diskio.Ref and an error are
 // returned.  The error returned (if non-nil) is always of type
 // *NodeError[Addr].  Notable errors that may be inside of the