Merge pull request #467 from Fesaa/feature/generics

Add a generic form of Selection.Map

go.mod

@@ -5,4 +5,4 @@ require (
 	golang.org/x/net v0.17.0
 )
 
-go 1.13
+go 1.18

iteration.go

@@ -37,3 +37,12 @@ func (s *Selection) Map(f func(int, *Selection) string) (result []string) {
 
 	return result
 }
+
+// Generic version of Selection.Map, allowing any type to be returned.
+func Map[E any](s *Selection, f func(int, *Selection) E) (result []E) {
+	for i, n := range s.Nodes {
+		result = append(result, f(i, newSingleSelection(n, s.document)))
+	}
+
+	return result
+}

iteration_test.go

@@ -86,3 +86,22 @@ func TestForRange(t *testing.T) {
 		t.Errorf("expected initial selection to still have length %d, got %d", initLen, sel.Length())
 	}
 }
+
+func TestGenericMap(t *testing.T) {
+	sel := Doc().Find(".pvk-content")
+	vals := Map(sel, func(i int, s *Selection) *html.NodeType {
+		n := s.Get(0)
+		if n.Type == html.ElementNode {
+			return &n.Type
+		}
+		return nil
+	})
+	for _, v := range vals {
+		if v == nil || *v != html.ElementNode {
+			t.Error("Expected Map array result to be all 'div's.")
+		}
+	}
+	if len(vals) != 3 {
+		t.Errorf("Expected Map array result to have a length of 3, found %v.", len(vals))
+	}
+}