more linter fixes

day134/problem.go

@@ -9,7 +9,7 @@ type SparseArray struct {
 	size int
 }
 
-var errIndexOutOfRange = fmt.Errorf("Index is out of range")
+var errIndexOutOfRange = fmt.Errorf("index is out of range")
 
 // ErrIndexOutOfRange returns the error that's associated with access beyond
 // the limits of the SparseArray.
@@ -31,7 +31,7 @@ func NewSparseArray(arr []int) *SparseArray {
 // Set mutates the value at position 'i' with value 'val'.
 func (sa *SparseArray) Set(i, val int) error {
 	if sa == nil {
-		return fmt.Errorf("Create with NewSparseArray")
+		return fmt.Errorf("create with NewSparseArray")
 	}
 	if i >= sa.size || i < 0 {
 		return errIndexOutOfRange
@@ -47,7 +47,7 @@ func (sa *SparseArray) Set(i, val int) error {
 // Get returns the value at position 'i'.
 func (sa *SparseArray) Get(i int) (int, error) {
 	if sa == nil {
-		return 0, fmt.Errorf("Create with NewSparseArray")
+		return 0, fmt.Errorf("create with NewSparseArray")
 	}
 	if i >= sa.size || i < 0 {
 		return 0, errIndexOutOfRange

day134/problem_test.go

@@ -13,11 +13,15 @@ func TestSparseArray(t *testing.T) {
 			t.Errorf("Expected (%v,%v) got (%v,%v)", val, nil, result, err)
 		}
 	}
-	sa.Set(0, 10)
+	if err := sa.Set(0, 10); err != nil {
+		t.Error("set shouldn't return an error", err)
+	}
 	if result, err := sa.Get(0); result != 10 || err != nil {
-		t.Errorf("Set didn't work properly")
+		t.Error("Set didn't work properly")
+	}
+	if err := sa.Set(0, 0); err != nil {
+		t.Error("set shouldn't return an error", err)
 	}
-	sa.Set(0, 0)
 	for i, val := range arr {
 		if result, err := sa.Get(i); result != val || err != nil {
 			t.Errorf("Expected (%v,%v) got (%v,%v)", val, nil, result, err)
@@ -51,8 +55,11 @@ func BenchmarkSparseArray(b *testing.B) {
 	arr := []int{0, 0, 0, 0, 9, 8, 7, 6, 0, 0}
 	sa := NewSparseArray(arr)
 	for i := 0; i < b.N; i++ {
+		//nolint: errcheck
 		sa.Set(0, 10)
+		//nolint: errcheck
 		sa.Get(0)
+		//nolint: errcheck
 		sa.Set(0, 0)
 
 	}

day188/problem.go

@@ -5,7 +5,7 @@ func MakeFunctionsOriginal() []func() int {
 	var funcList []func() int
 	for _, i := range []int{1, 2, 3} {
 		funcList = append(funcList, func() int {
-			return i
+			return i //nolint: scopelint
 		})
 	}
 	return funcList

day20/problem_test.go

@@ -11,10 +11,10 @@ func createTwoSharedLists() (*Node, *Node, *Node) {
 	return one, two, common
 }
 
-func createTwoIndependentLists() (*Node, *Node, *Node) {
+func createTwoIndependentLists() (*Node, *Node) {
 	one := &Node{"abc", &Node{"def", &Node{"ghi", nil}}}
 	two := &Node{111, nil}
-	return one, two, nil
+	return one, two
 }
 
 func TestFindCommonNode(t *testing.T) {
@@ -27,19 +27,19 @@ func TestFindCommonNode(t *testing.T) {
 	if result := FindCommonNode(one, two); result != common {
 		t.Error("Expected these two be the same pointer")
 	}
-	one, two, common = createTwoIndependentLists()
-	if result := FindCommonNode(one, two); result != common {
+	one, two = createTwoIndependentLists()
+	if result := FindCommonNode(one, two); result != nil {
 		t.Error("Expected these two be nil")
 	}
 	one, two = two, one // swap
-	if result := FindCommonNode(one, two); result != common {
+	if result := FindCommonNode(one, two); result != nil {
 		t.Error("Expected these two be nil")
 	}
 }
 
 func BenchmarkFindCommonNode(b *testing.B) {
 	one, two, _ := createTwoSharedLists()
-	onei, twoi, _ := createTwoIndependentLists()
+	onei, twoi := createTwoIndependentLists()
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
 		FindCommonNode(one, two)

day87/problem.go

@@ -50,15 +50,16 @@ func IsValidRules(rules []string) bool {
 		toPos, toFound := positions[to]
 		fromPos, fromFound := positions[from]
 		delta := directions[dir]
-		if toFound && fromFound {
+		switch {
+		case toFound && fromFound:
 			if !checkValid(fromPos, toPos, dir) {
 				return false
 			}
-		} else if toFound && !fromFound {
+		case toFound && !fromFound:
 			positions[from] = Position{toPos.X - delta.X, toPos.Y - delta.Y}
-		} else if !toFound && fromFound {
+		case !toFound && fromFound:
 			positions[to] = Position{fromPos.X + delta.X, fromPos.Y + delta.Y}
-		} else {
+		default:
 			positions[from] = Position{0, 0}
 			positions[to] = directions[dir]
 		}

day9/problem.go

@@ -5,11 +5,12 @@ package day9
 func MaximumNonAdjacentSum(nums []int) int {
 	var one, two, result int
 	for i, val := range nums {
-		if i == 0 {
+		switch {
+		case i == 0:
 			result = val
-		} else if i == 1 {
+		case i == 1:
 			result = max(result, val)
-		} else {
+		default:
 			result = max(one, val+two)
 		}
 		two = one

day91/problem.go

@@ -5,7 +5,7 @@ func BadSnippet() []int {
 	funcs := make([]func() int, 9)
 	for i := 0; i < 9; i++ {
 		funcs[i] = func() int {
-			return i
+			return i //nolint: scopelint
 		}
 	}
 	result := make([]int, 9)