Expand assertion statements.

This commit expands calls to _assert() that use variadic arguments. These calls require conversion to interface{} so there
was a large number of calls to Go's internal convT2E() function. In some profiling this was taking over 20% of total runtime.
I don't remember seeing this before Go 1.4 so perhaps something has changed.

bucket.go

@@ -511,8 +511,12 @@ func (b *Bucket) spill() error {
 		// Update parent node.
 		var c = b.Cursor()
 		k, _, flags := c.seek([]byte(name))
-		_assert(bytes.Equal([]byte(name), k), "misplaced bucket header: %x -> %x", []byte(name), k)
+		if !bytes.Equal([]byte(name), k) {
-		_assert(flags&bucketLeafFlag != 0, "unexpected bucket header flag: %x", flags)
+			panic(fmt.Sprintf("misplaced bucket header: %x -> %x", []byte(name), k))
+		}
+		if flags&bucketLeafFlag == 0 {
+			panic(fmt.Sprintf("unexpected bucket header flag: %x", flags))
+		}
 		c.node().put([]byte(name), []byte(name), value, 0, bucketLeafFlag)
 	}
 
@@ -528,7 +532,9 @@ func (b *Bucket) spill() error {
 	b.rootNode = b.rootNode.root()
 
 	// Update the root node for this bucket.
-	_assert(b.rootNode.pgid < b.tx.meta.pgid, "pgid (%d) above high water mark (%d)", b.rootNode.pgid, b.tx.meta.pgid)
+	if b.rootNode.pgid >= b.tx.meta.pgid {
+		panic(fmt.Sprintf("pgid (%d) above high water mark (%d)", b.rootNode.pgid, b.tx.meta.pgid))
+	}
 	b.root = b.rootNode.pgid
 
 	return nil
@@ -659,7 +665,9 @@ func (b *Bucket) pageNode(id pgid) (*page, *node) {
 	// Inline buckets have a fake page embedded in their value so treat them
 	// differently. We'll return the rootNode (if available) or the fake page.
 	if b.root == 0 {
-		_assert(id == 0, "inline bucket non-zero page access(2): %d != 0", id)
+		if id != 0 {
+			panic(fmt.Sprintf("inline bucket non-zero page access(2): %d != 0", id))
+		}
 		if b.rootNode != nil {
 			return nil, b.rootNode
 		}

cursor.go

@@ -2,6 +2,7 @@ package bolt
 
 import (
 	"bytes"
+	"fmt"
 	"sort"
 )
 
@@ -228,8 +229,8 @@ func (c *Cursor) next() (key []byte, value []byte, flags uint32) {
 // search recursively performs a binary search against a given page/node until it finds a given key.
 func (c *Cursor) search(key []byte, pgid pgid) {
 	p, n := c.bucket.pageNode(pgid)
-	if p != nil {
+	if p != nil && (p.flags&(branchPageFlag|leafPageFlag)) == 0 {
-		_assert((p.flags&(branchPageFlag|leafPageFlag)) != 0, "invalid page type: %d: %x", p.id, p.flags)
+		panic(fmt.Sprintf("invalid page type: %d: %x", p.id, p.flags))
 	}
 	e := elemRef{page: p, node: n}
 	c.stack = append(c.stack, e)

db.go

@@ -664,9 +664,11 @@ func (m *meta) copy(dest *meta) {
 
 // write writes the meta onto a page.
 func (m *meta) write(p *page) {
-
+	if m.root.root >= m.pgid {
-	_assert(m.root.root < m.pgid, "root bucket pgid (%d) above high water mark (%d)", m.root.root, m.pgid)
+		panic(fmt.Sprintf("root bucket pgid (%d) above high water mark (%d)", m.root.root, m.pgid))
-	_assert(m.freelist < m.pgid, "freelist pgid (%d) above high water mark (%d)", m.freelist, m.pgid)
+	} else if m.freelist >= m.pgid {
+		panic(fmt.Sprintf("freelist pgid (%d) above high water mark (%d)", m.freelist, m.pgid))
+	}
 
 	// Page id is either going to be 0 or 1 which we can determine by the transaction ID.
 	p.id = pgid(m.txid % 2)

freelist.go

@@ -1,6 +1,7 @@
 package bolt
 
 import (
+	"fmt"
 	"sort"
 	"unsafe"
 )
@@ -67,7 +68,9 @@ func (f *freelist) allocate(n int) pgid {
 
 	var initial, previd pgid
 	for i, id := range f.ids {
-		_assert(id > 1, "invalid page allocation: %d", id)
+		if id <= 1 {
+			panic(fmt.Sprintf("invalid page allocation: %d", id))
+		}
 
 		// Reset initial page if this is not contiguous.
 		if previd == 0 || id-previd != 1 {
@@ -103,13 +106,17 @@ func (f *freelist) allocate(n int) pgid {
 // free releases a page and its overflow for a given transaction id.
 // If the page is already free then a panic will occur.
 func (f *freelist) free(txid txid, p *page) {
-	_assert(p.id > 1, "cannot free page 0 or 1: %d", p.id)
+	if p.id <= 1 {
+		panic(fmt.Sprintf("cannot free page 0 or 1: %d", p.id))
+	}
 
 	// Free page and all its overflow pages.
 	var ids = f.pending[txid]
 	for id := p.id; id <= p.id+pgid(p.overflow); id++ {
 		// Verify that page is not already free.
-		_assert(!f.cache[id], "page %d already freed", id)
+		if f.cache[id] {
+			panic(fmt.Sprintf("page %d already freed", id))
+		}
 
 		// Add to the freelist and cache.
 		ids = append(ids, id)

node.go

@@ -2,6 +2,7 @@ package bolt
 
 import (
 	"bytes"
+	"fmt"
 	"sort"
 	"unsafe"
 )
@@ -70,7 +71,9 @@ func (n *node) pageElementSize() int {
 
 // childAt returns the child node at a given index.
 func (n *node) childAt(index int) *node {
-	_assert(!n.isLeaf, "invalid childAt(%d) on a leaf node", index)
+	if n.isLeaf {
+		panic(fmt.Sprintf("invalid childAt(%d) on a leaf node", index))
+	}
 	return n.bucket.node(n.inodes[index].pgid, n)
 }
 
@@ -111,9 +114,13 @@ func (n *node) prevSibling() *node {
 
 // put inserts a key/value.
 func (n *node) put(oldKey, newKey, value []byte, pgid pgid, flags uint32) {
-	_assert(pgid < n.bucket.tx.meta.pgid, "pgid (%d) above high water mark (%d)", pgid, n.bucket.tx.meta.pgid)
+	if pgid >= n.bucket.tx.meta.pgid {
-	_assert(len(oldKey) > 0, "put: zero-length old key")
+		panic(fmt.Sprintf("pgid (%d) above high water mark (%d)", pgid, n.bucket.tx.meta.pgid))
-	_assert(len(newKey) > 0, "put: zero-length new key")
+	} else if len(oldKey) <= 0 {
+		panic("put: zero-length old key")
+	} else if len(newKey) <= 0 {
+		panic("put: zero-length new key")
+	}
 
 	// Find insertion index.
 	index := sort.Search(len(n.inodes), func(i int) bool { return bytes.Compare(n.inodes[i].key, oldKey) != -1 })
@@ -189,7 +196,9 @@ func (n *node) write(p *page) {
 		p.flags |= branchPageFlag
 	}
 
-	_assert(len(n.inodes) < 0xFFFF, "inode overflow: %d (pgid=%d)", len(n.inodes), p.id)
+	if len(n.inodes) >= 0xFFFF {
+		panic(fmt.Sprintf("inode overflow: %d (pgid=%d)", len(n.inodes), p.id))
+	}
 	p.count = uint16(len(n.inodes))
 
 	// Loop over each item and write it to the page.
@@ -348,7 +357,9 @@ func (n *node) spill() error {
 		}
 
 		// Write the node.
-		_assert(p.id < tx.meta.pgid, "pgid (%d) above high water mark (%d)", p.id, tx.meta.pgid)
+		if p.id >= tx.meta.pgid {
+			panic(fmt.Sprintf("pgid (%d) above high water mark (%d)", p.id, tx.meta.pgid))
+		}
 		node.pgid = p.id
 		node.write(p)
 		node.spilled = true