Add full test coverage to tpage.

2 files changed, 67 insertions, 6 deletions

diff --git a/tpage.go b/tpage.go
index 07fe641..facc789 100644
--- a/tpage.go
+++ b/tpage.go
@@ -88,8 +88,8 @@ func (p *tpage) write(pageSize int, allocate allocator) ([]*page, error) {
 
 // split divides up the noes in the page into appropriately sized groups.
 func (p *tpage) split(pageSize int) []tnodes {
-	// If we only have enough nodes for one page then just return the nodes.
-	if len(p.nodes) <= minKeysPerPage {
+	// If we only have enough nodes for multiple pages then just return the nodes.
+	if len(p.nodes) <= (minKeysPerPage * 2) {
 		return []tnodes{p.nodes}
 	}
 
@@ -110,19 +110,22 @@ func (p *tpage) split(pageSize int) []tnodes {
 	// Set fill threshold to 25%.
 	threshold := pageSize >> 4
 
-	for _, node := range p.nodes {
+	for index, node := range p.nodes {
 		nodeSize := lnodeSize + len(node.key) + len(node.value)
 
 		// TODO(benbjohnson): Don't create a new group for just the last node.
-		if group == nil || (len(group) > minKeysPerPage && size+nodeSize > threshold) {
+		if group == nil || (len(group) >= minKeysPerPage && index < len(p.nodes)-minKeysPerPage && size+nodeSize > threshold) {
 			size = pageHeaderSize
+			if group != nil {
+				groups = append(groups, group)
+			}
 			group = make(tnodes, 0)
-			groups = append(groups, group)
 		}
 
 		size += nodeSize
 		group = append(group, node)
 	}
+	groups = append(groups, group)
 
 	return groups
 }
diff --git a/tpage_test.go b/tpage_test.go
index 389a176..ace4c53 100644
--- a/tpage_test.go
+++ b/tpage_test.go
@@ -79,7 +79,65 @@ func TestTpageWrite(t *testing.T) {
 	assert.Equal(t, p2.nodes[2].value, []byte("que"))
 }
 
+// Ensure that an error that an allocation error during writing is returned.
+func TestTpageWriteError(t *testing.T) {
+	// Create a temp page.
+	p := &tpage{nodes: make(tnodes, 0)}
+	p.put([]byte("susy"), []byte("que"))
+
+	// Write it to a page.
+	exp := &Error{}
+	allocate := func(size int) (*page, error) {
+		return nil, exp
+	}
+	pages, err := p.write(4096, allocate)
+	assert.Nil(t, pages)
+	assert.Equal(t, err, exp)
+}
+
 // Ensure that a temporary page can split into appropriate subgroups.
 func TestTpageSplit(t *testing.T) {
-	t.Skip("pending")
+	// Create a temp page.
+	p := &tpage{nodes: make(tnodes, 0)}
+	p.put([]byte("00000001"), []byte("0123456701234567"))
+	p.put([]byte("00000002"), []byte("0123456701234567"))
+	p.put([]byte("00000003"), []byte("0123456701234567"))
+	p.put([]byte("00000004"), []byte("0123456701234567"))
+	p.put([]byte("00000005"), []byte("0123456701234567"))
+
+	// Split between 3 & 4.
+	pages := p.split(100)
+
+	assert.Equal(t, len(pages), 2)
+	assert.Equal(t, len(pages[0]), 2)
+	assert.Equal(t, len(pages[1]), 3)
+}
+
+// Ensure that a temporary page with the minimum number of nodes just returns a single split group.
+func TestTpageSplitWithMinKeys(t *testing.T) {
+	// Create a temp page.
+	p := &tpage{nodes: make(tnodes, 0)}
+	p.put([]byte("00000001"), []byte("0123456701234567"))
+	p.put([]byte("00000002"), []byte("0123456701234567"))
+
+	// Split.
+	pages := p.split(20)
+	assert.Equal(t, len(pages), 1)
+	assert.Equal(t, len(pages[0]), 2)
+}
+
+// Ensure that a temporary page that has keys that all fit on a page just returns one split group.
+func TestTpageSplitFitsInPage(t *testing.T) {
+	// Create a temp page.
+	p := &tpage{nodes: make(tnodes, 0)}
+	p.put([]byte("00000001"), []byte("0123456701234567"))
+	p.put([]byte("00000002"), []byte("0123456701234567"))
+	p.put([]byte("00000003"), []byte("0123456701234567"))
+	p.put([]byte("00000004"), []byte("0123456701234567"))
+	p.put([]byte("00000005"), []byte("0123456701234567"))
+
+	// Split.
+	pages := p.split(4096)
+	assert.Equal(t, len(pages), 1)
+	assert.Equal(t, len(pages[0]), 5)
 }