Fix lint issues

.golangci.yml

@@ -19,8 +19,22 @@ linters:
     - nosnakecase
     - maligned
 
+linters-settings:
+  ireturn:
+    allow:
+      - anon
+      - error
+      - empty
+      - stdlib
+      - generic
+      - T
+
 issues:
   exclude-rules:
     - path: '_test\.go'
       linters:
         - funlen
+
+    - source: 'ok bool'
+      linters:
+        - nonamedreturns

internal/lists/linked_list.go

@@ -47,14 +47,14 @@ func (l *LinkedList[T]) ElementAt(index int) (value T, ok bool) {
 		return value, false
 	}
 
-	i := 0
-	for currentNode := l.head; currentNode != nil; currentNode = currentNode.next {
-		if i == index {
+	for currentNodeIndex, currentNode := 0, l.head; currentNode != nil; currentNode = currentNode.next {
+		if currentNodeIndex == index {
 			value = currentNode.value
+
 			break
 		}
 
-		i++
+		currentNodeIndex++
 	}
 
 	return value, true

internal/maps/contains_key.go

@@ -3,5 +3,6 @@ package maps
 // ContainsKey returns true if and only if elem is a key defined in _map.
 func ContainsKey[T comparable, V any](_map map[T]V, elem T) bool {
 	_, ok := _map[elem]
+
 	return ok
 }

internal/routes/errors.go

@@ -2,22 +2,22 @@ package routes
 
 import "fmt"
 
-// ErrRouteAlreadyDefined is the error for already defined routes.
-type ErrRouteAlreadyDefined struct {
+// RouteAlreadyDefinedError is the error for already defined routes.
+type RouteAlreadyDefinedError struct {
 	Route Route
 }
 
-func (e ErrRouteAlreadyDefined) Error() string {
+func (e RouteAlreadyDefinedError) Error() string {
 	return fmt.Sprintf("%s has been already defined", e.Route)
 }
 
-// ErrDuplicateArguments is the error for duplicate arguments in the same pattern.
+// DuplicateArgumentsError is the error for duplicate arguments in the same pattern.
 //
-// Example: /users/:id/books/:id
-type ErrDuplicateArguments struct {
+// Example: /users/:id/books/:id.
+type DuplicateArgumentsError struct {
 	Duplicate string
 }
 
-func (e ErrDuplicateArguments) Error() string {
+func (e DuplicateArgumentsError) Error() string {
 	return fmt.Sprintf("a pattern can not contain two arguments with the same name (%s)", e.Duplicate)
 }

internal/routes/graph.go

@@ -18,15 +18,15 @@ func NewGraph() Graph {
 // CanBeInserted checks if route can be defined in this graph.
 //
 // If it can't be inserted (ok equals false), CanBeInserted returns the reason error.
-func (g Graph) CanBeInserted(route Route) (reason error, ok bool) {
+func (g Graph) CanBeInserted(route Route) (ok bool, reason error) {
 	routePath := append(route.Path(), terminalNode)
 
 	if duplicate, has := hasDuplicateArguments(routePath); has {
-		return ErrDuplicateArguments{duplicate}, false
+		return false, DuplicateArgumentsError{duplicate}
 	}
 
 	if !maps.ContainsKey(g, route.Method) {
-		return nil, true
+		return true, nil
 	}
 
 	previousNode := route.Method
@@ -38,13 +38,13 @@ func (g Graph) CanBeInserted(route Route) (reason error, ok bool) {
 		}
 
 		if !maps.ContainsKey(g, path) || !slices.Contains(adjacentNodes, path) {
-			return nil, true
+			return true, nil
 		}
 
 		previousNode = path
 	}
 
-	return ErrRouteAlreadyDefined{route}, false
+	return false, RouteAlreadyDefinedError{route}
 }
 
 // Add adds the route to this graph.
@@ -102,6 +102,7 @@ func (g Graph) matchAdjacentNode(parent string, path []string, pathIndex int, ma
 		}
 
 		match.addPathFragmentAtBeginning(child)
+
 		return true
 	}
 
@@ -116,6 +117,7 @@ func (g Graph) matchAdjacentNode(parent string, path []string, pathIndex int, ma
 		}
 
 		match.addPathArgumentAtBeginning(childrenArguments[i], child)
+
 		return true
 	}
 

internal/routes/graph_test.go

@@ -53,7 +53,7 @@ func TestGraph_CanBeInserted(t *testing.T) {
 				routes.NewRoute("/users/:id", http.MethodGet),
 			},
 			routeToCheck: routes.NewRoute("/users/:user_id", http.MethodGet),
-			expectedError: routes.ErrRouteAlreadyDefined{
+			expectedError: routes.RouteAlreadyDefinedError{
 				Route: routes.NewRoute("/users/:user_id", http.MethodGet),
 			},
 			expectedOk: false,
@@ -62,7 +62,7 @@ func TestGraph_CanBeInserted(t *testing.T) {
 			name:          "UndefinedRoute_DuplicateParameters",
 			currentRoutes: []routes.Route{},
 			routeToCheck:  routes.NewRoute("/users/:id/books/:id", http.MethodGet),
-			expectedError: routes.ErrDuplicateArguments{Duplicate: ":id"},
+			expectedError: routes.DuplicateArgumentsError{Duplicate: ":id"},
 			expectedOk:    false,
 		},
 		{
@@ -71,7 +71,7 @@ func TestGraph_CanBeInserted(t *testing.T) {
 				routes.NewRoute("/users/:id", http.MethodGet),
 			},
 			routeToCheck: routes.NewRoute("/users/:user_id", http.MethodGet),
-			expectedError: routes.ErrRouteAlreadyDefined{
+			expectedError: routes.RouteAlreadyDefinedError{
 				Route: routes.NewRoute("/users/:user_id", http.MethodGet),
 			},
 			expectedOk: false,
@@ -90,11 +90,11 @@ func TestGraph_CanBeInserted(t *testing.T) {
 			}
 
 			// Act
-			actualError, actualOk := graph.CanBeInserted(test.routeToCheck)
+			actualOk, actualError := graph.CanBeInserted(test.routeToCheck)
 
 			// Assert
-			require.ErrorIs(t, test.expectedError, actualError)
 			require.Equal(t, test.expectedOk, actualOk)
+			require.ErrorIs(t, test.expectedError, actualError)
 		})
 	}
 }

internal/sets/hash_set.go

@@ -26,5 +26,6 @@ func (s HashSet[T]) Len() int {
 // Contains returns true if and only if elem is contained in this set.
 func (s HashSet[T]) Contains(elem T) bool {
 	_, ok := s[elem]
+
 	return ok
 }

router.go

@@ -38,7 +38,7 @@ func NewRouter() *Router {
 func (r *Router) Handle(pattern string, method string, handler HandleFunc) {
 	route := routes.NewRoute(pattern, method)
 
-	if err, ok := r.graph.CanBeInserted(route); !ok {
+	if ok, err := r.graph.CanBeInserted(route); !ok {
 		panic(err)
 	}