🩹 Fix: sorting error in sortAcceptedTypes (#3331)

* 🩹 Fix: correct sorting error in sortAcceptedTypes.

* ♻️ Refactor: remove redundant branch

---------

Co-authored-by: Juan Calderon-Perez <[email protected]>

Author: ksw2000

helpers.go

@@ -483,7 +483,7 @@ func getOffer(header []byte, isAccepted func(spec, offer string, specParams head
 
 	if len(acceptedTypes) > 1 {
 		// Sort accepted types by quality and specificity, preserving order of equal elements
-		sortAcceptedTypes(&acceptedTypes)
+		sortAcceptedTypes(acceptedTypes)
 	}
 
 	// Find the first offer that matches the accepted types
@@ -511,19 +511,14 @@ func getOffer(header []byte, isAccepted func(spec, offer string, specParams head
 // A type with parameters has higher priority than an equivalent one without parameters.
 // e.g., text/html;a=1;b=2 comes before text/html;a=1
 // See: https://www.rfc-editor.org/rfc/rfc9110#name-content-negotiation-fields
-func sortAcceptedTypes(acceptedTypes *[]acceptedType) {
-	if acceptedTypes == nil || len(*acceptedTypes) < 2 {
-		return
-	}
-	at := *acceptedTypes
-
+func sortAcceptedTypes(at []acceptedType) {
 	for i := 1; i < len(at); i++ {
 		lo, hi := 0, i-1
 		for lo <= hi {
 			mid := (lo + hi) / 2
 			if at[i].quality < at[mid].quality ||
 				(at[i].quality == at[mid].quality && at[i].specificity < at[mid].specificity) ||
-				(at[i].quality == at[mid].quality && at[i].specificity < at[mid].specificity && len(at[i].params) < len(at[mid].params)) ||
+				(at[i].quality == at[mid].quality && at[i].specificity == at[mid].specificity && len(at[i].params) < len(at[mid].params)) ||
 				(at[i].quality == at[mid].quality && at[i].specificity == at[mid].specificity && len(at[i].params) == len(at[mid].params) && at[i].order > at[mid].order) {
 				lo = mid + 1
 			} else {

helpers_test.go

@@ -354,7 +354,6 @@ func Test_Utils_SortAcceptedTypes(t *testing.T) {
 		{spec: "text/html", quality: 1, specificity: 3, order: 0},
 		{spec: "text/*", quality: 0.5, specificity: 2, order: 1},
 		{spec: "*/*", quality: 0.1, specificity: 1, order: 2},
-		{spec: "application/json", quality: 0.999, specificity: 3, order: 3},
 		{spec: "application/xml", quality: 1, specificity: 3, order: 4},
 		{spec: "application/pdf", quality: 1, specificity: 3, order: 5},
 		{spec: "image/png", quality: 1, specificity: 3, order: 6},
@@ -363,8 +362,9 @@ func Test_Utils_SortAcceptedTypes(t *testing.T) {
 		{spec: "image/gif", quality: 1, specificity: 3, order: 9},
 		{spec: "text/plain", quality: 1, specificity: 3, order: 10},
 		{spec: "application/json", quality: 0.999, specificity: 3, params: headerParams{"a": []byte("1")}, order: 11},
+		{spec: "application/json", quality: 0.999, specificity: 3, order: 3},
 	}
-	sortAcceptedTypes(&acceptedTypes)
+	sortAcceptedTypes(acceptedTypes)
 	require.Equal(t, []acceptedType{
 		{spec: "text/html", quality: 1, specificity: 3, order: 0},
 		{spec: "application/xml", quality: 1, specificity: 3, order: 4},
@@ -390,7 +390,7 @@ func Benchmark_Utils_SortAcceptedTypes_Sorted(b *testing.B) {
 		acceptedTypes[0] = acceptedType{spec: "text/html", quality: 1, specificity: 1, order: 0}
 		acceptedTypes[1] = acceptedType{spec: "text/*", quality: 0.5, specificity: 1, order: 1}
 		acceptedTypes[2] = acceptedType{spec: "*/*", quality: 0.1, specificity: 1, order: 2}
-		sortAcceptedTypes(&acceptedTypes)
+		sortAcceptedTypes(acceptedTypes)
 	}
 	require.Equal(b, "text/html", acceptedTypes[0].spec)
 	require.Equal(b, "text/*", acceptedTypes[1].spec)
@@ -414,7 +414,7 @@ func Benchmark_Utils_SortAcceptedTypes_Unsorted(b *testing.B) {
 		acceptedTypes[8] = acceptedType{spec: "image/*", quality: 1, specificity: 2, order: 8}
 		acceptedTypes[9] = acceptedType{spec: "image/gif", quality: 1, specificity: 3, order: 9}
 		acceptedTypes[10] = acceptedType{spec: "text/plain", quality: 1, specificity: 3, order: 10}
-		sortAcceptedTypes(&acceptedTypes)
+		sortAcceptedTypes(acceptedTypes)
 	}
 	require.Equal(b, []acceptedType{
 		{spec: "text/html", quality: 1, specificity: 3, order: 0},