diff --git a/golden_test.go b/golden_test.go
index 0cf5857..b721a28 100644
--- a/golden_test.go
+++ b/golden_test.go
@@ -22,41 +22,41 @@ type Golden struct {
 }
 
 var golden = []Golden{
-	{"day", day_in, day_out},
-	{"offset", offset_in, offset_out},
-	{"gap", gap_in, gap_out},
-	{"num", num_in, num_out},
-	{"unum", unum_in, unum_out},
-	{"prime", prime_in, prime_out},
+	{"day", dayIn, dayOut},
+	{"offset", offsetIn, offsetOut},
+	{"gap", gapIn, gapOut},
+	{"num", numIn, numOut},
+	{"unum", unumIn, unumOut},
+	{"prime", primeIn, primeOut},
 }
 
 var goldenJSON = []Golden{
-	{"prime", prime_json_in, prime_json_out},
+	{"prime", primeJsonIn, primeJsonOut},
 }
 var goldenText = []Golden{
-	{"prime", prime_text_in, prime_text_out},
+	{"prime", primeTextIn, primeTextOut},
 }
 
 var goldenYAML = []Golden{
-	{"prime", prime_yaml_in, prime_yaml_out},
+	{"prime", primeYamlIn, primeYamlOut},
 }
 
 var goldenSQL = []Golden{
-	{"prime", prime_sql_in, prime_sql_out},
+	{"prime", primeSqlIn, primeSqlOut},
 }
 
 var goldenJSONAndSQL = []Golden{
-	{"prime", prime_json_and_sql_in, prime_json_and_sql_out},
+	{"prime", primeJsonAndSqlIn, primeJsonAndSqlOut},
 }
 
 var goldenPrefix = []Golden{
-	{"prefix", prefix_in, day_out},
+	{"prefix", prefixIn, dayOut},
 }
 
 // Each example starts with "type XXX [u]int", with a single space separating them.
 
 // Simple test: enumeration of type int starting at 0.
-const day_in = `type Day int
+const dayIn = `type Day int
 const (
 	Monday Day = iota
 	Tuesday
@@ -68,7 +68,7 @@ const (
 )
 `
 
-const day_out = `
+const dayOut = `
 const _DayName = "MondayTuesdayWednesdayThursdayFridaySaturdaySunday"
 
 var _DayIndex = [...]uint8{0, 6, 13, 22, 30, 36, 44, 50}
@@ -119,7 +119,7 @@ func (i Day) IsADay() bool {
 
 // Enumeration with an offset.
 // Also includes a duplicate.
-const offset_in = `type Number int
+const offsetIn = `type Number int
 const (
 	_ Number = iota
 	One
@@ -129,7 +129,7 @@ const (
 )
 `
 
-const offset_out = `
+const offsetOut = `
 const _NumberName = "OneTwoThree"
 
 var _NumberIndex = [...]uint8{0, 3, 6, 11}
@@ -176,7 +176,7 @@ func (i Number) IsANumber() bool {
 `
 
 // Gaps and an offset.
-const gap_in = `type Gap int
+const gapIn = `type Gap int
 const (
 	Two Gap = 2
 	Three Gap = 3
@@ -189,7 +189,7 @@ const (
 )
 `
 
-const gap_out = `
+const gapOut = `
 const (
 	_GapName_0 = "TwoThree"
 	_GapName_1 = "FiveSixSevenEightNine"
@@ -256,7 +256,7 @@ func (i Gap) IsAGap() bool {
 `
 
 // Signed integers spanning zero.
-const num_in = `type Num int
+const numIn = `type Num int
 const (
 	m_2 Num = -2 + iota
 	m_1
@@ -266,7 +266,7 @@ const (
 )
 `
 
-const num_out = `
+const numOut = `
 const _NumName = "m_2m_1m0m1m2"
 
 var _NumIndex = [...]uint8{0, 3, 6, 8, 10, 12}
@@ -315,7 +315,7 @@ func (i Num) IsANum() bool {
 `
 
 // Unsigned integers spanning zero.
-const unum_in = `type Unum uint
+const unumIn = `type Unum uint
 const (
 	m_2 Unum = iota + 253
 	m_1
@@ -328,7 +328,7 @@ const (
 )
 `
 
-const unum_out = `
+const unumOut = `
 const (
 	_UnumName_0 = "m0m1m2"
 	_UnumName_1 = "m_2m_1"
@@ -388,7 +388,7 @@ func (i Unum) IsAUnum() bool {
 
 // Enough gaps to trigger a map implementation of the method.
 // Also includes a duplicate to test that it doesn't cause problems
-const prime_in = `type Prime int
+const primeIn = `type Prime int
 const (
 	p2 Prime = 2
 	p3 Prime = 3
@@ -407,7 +407,7 @@ const (
 )
 `
 
-const prime_out = `
+const primeOut = `
 const _PrimeName = "p2p3p5p7p11p13p17p19p23p29p37p41p43"
 
 var _PrimeMap = map[Prime]string{
@@ -471,7 +471,7 @@ func (i Prime) IsAPrime() bool {
 	return ok
 }
 `
-const prime_json_in = `type Prime int
+const primeJsonIn = `type Prime int
 const (
 	p2 Prime = 2
 	p3 Prime = 3
@@ -490,7 +490,7 @@ const (
 )
 `
 
-const prime_json_out = `
+const primeJsonOut = `
 const _PrimeName = "p2p3p5p7p11p13p17p19p23p29p37p41p43"
 
 var _PrimeMap = map[Prime]string{
@@ -572,7 +572,7 @@ func (i *Prime) UnmarshalJSON(data []byte) error {
 }
 `
 
-const prime_text_in = `type Prime int
+const primeTextIn = `type Prime int
 const (
 	p2 Prime = 2
 	p3 Prime = 3
@@ -591,7 +591,7 @@ const (
 )
 `
 
-const prime_text_out = `
+const primeTextOut = `
 const _PrimeName = "p2p3p5p7p11p13p17p19p23p29p37p41p43"
 
 var _PrimeMap = map[Prime]string{
@@ -668,7 +668,7 @@ func (i *Prime) UnmarshalText(text []byte) error {
 }
 `
 
-const prime_yaml_in = `type Prime int
+const primeYamlIn = `type Prime int
 const (
 	p2 Prime = 2
 	p3 Prime = 3
@@ -687,7 +687,7 @@ const (
 )
 `
 
-const prime_yaml_out = `
+const primeYamlOut = `
 const _PrimeName = "p2p3p5p7p11p13p17p19p23p29p37p41p43"
 
 var _PrimeMap = map[Prime]string{
@@ -769,7 +769,7 @@ func (i *Prime) UnmarshalYAML(unmarshal func(interface{}) error) error {
 }
 `
 
-const prime_sql_in = `type Prime int
+const primeSqlIn = `type Prime int
 const (
 	p2 Prime = 2
 	p3 Prime = 3
@@ -788,7 +788,7 @@ const (
 )
 `
 
-const prime_sql_out = `
+const primeSqlOut = `
 const _PrimeName = "p2p3p5p7p11p13p17p19p23p29p37p41p43"
 
 var _PrimeMap = map[Prime]string{
@@ -881,7 +881,7 @@ func (i *Prime) Scan(value interface{}) error {
 }
 `
 
-const prime_json_and_sql_in = `type Prime int
+const primeJsonAndSqlIn = `type Prime int
 const (
 	p2 Prime = 2
 	p3 Prime = 3
@@ -900,7 +900,7 @@ const (
 )
 `
 
-const prime_json_and_sql_out = `
+const primeJsonAndSqlOut = `
 const _PrimeName = "p2p3p5p7p11p13p17p19p23p29p37p41p43"
 
 var _PrimeMap = map[Prime]string{
@@ -1010,7 +1010,7 @@ func (i *Prime) Scan(value interface{}) error {
 }
 `
 
-const prefix_in = `type Day int
+const prefixIn = `type Day int
 const (
 	DayMonday Day = iota
 	DayTuesday
diff --git a/stringer.go b/stringer.go
index 34447fb..78c36b2 100644
--- a/stringer.go
+++ b/stringer.go
@@ -191,6 +191,7 @@ type Generator struct {
 	pkg *Package     // Package we are scanning.
 }
 
+// Printf prints the string to the output
 func (g *Generator) Printf(format string, args ...interface{}) {
 	fmt.Fprintf(&g.buf, format, args...)
 }
@@ -204,6 +205,7 @@ type File struct {
 	values   []Value // Accumulator for constant values of that type.
 }
 
+// Package holds information about a Go package
 type Package struct {
 	dir      string
 	name     string
diff --git a/util_test.go b/util_test.go
index 1aeba6e..fa50393 100644
--- a/util_test.go
+++ b/util_test.go
@@ -22,11 +22,11 @@ type SplitTest struct {
 }
 
 var (
-	m2  = uint64(2)
-	m1  = uint64(1)
-	m0  = uint64(0)
-	m_1 = ^uint64(0)     // -1 when signed.
-	m_2 = ^uint64(0) - 1 // -2 when signed.
+	m2          = uint64(2)
+	m1          = uint64(1)
+	m0          = uint64(0)
+	m1Spanning0 = ^uint64(0)     // -1 when signed.
+	m2Spanning0 = ^uint64(0) - 1 // -2 when signed.
 )
 
 var splitTests = []SplitTest{
@@ -44,9 +44,9 @@ var splitTests = []SplitTest{
 	// Gaps throughout
 	{u{33, 44, 1, 32, 45, 31}, uu{u{1}, u{31, 32, 33}, u{44, 45}}, true},
 	// Unsigned values spanning 0.
-	{u{m1, m0, m_1, m2, m_2}, uu{u{m0, m1, m2}, u{m_2, m_1}}, false},
+	{u{m1, m0, m1Spanning0, m2, m2Spanning0}, uu{u{m0, m1, m2}, u{m2Spanning0, m1Spanning0}}, false},
 	// Signed values spanning 0
-	{u{m1, m0, m_1, m2, m_2}, uu{u{m_2, m_1, m0, m1, m2}}, true},
+	{u{m1, m0, m1Spanning0, m2, m2Spanning0}, uu{u{m2Spanning0, m1Spanning0, m0, m1, m2}}, true},
 }
 
 func TestSplitIntoRuns(t *testing.T) {