tpl: Allow 'Querify' to take lone slice/interface argument

Querify can now take a lone string/interface slice (with string
keys) as a parameter, or multiple string parameters, to build
URL queries.

Querify earlier used 'Dictionary' to add key/value pairs to a
map to build URL queries. Changed to dynamically generate ordered
key/value pairs. Cannot take string slice as key (earlier
possible due to Dictionary).

Added tests and benchmarks for querify.

Closes #6735

tpl/collections/collections_test.go

@@ -564,9 +564,16 @@ func TestQuerify(t *testing.T) {
 	}{
 		{[]interface{}{"a", "b"}, "a=b"},
 		{[]interface{}{"a", "b", "c", "d", "f", " &"}, `a=b&c=d&f=+%26`},
+		{[]interface{}{[]string{"a", "b"}}, "a=b"},
+		{[]interface{}{[]string{"a", "b", "c", "d", "f", " &"}}, `a=b&c=d&f=+%26`},
+		{[]interface{}{[]interface{}{"x", "y"}}, `x=y`},
+		{[]interface{}{[]interface{}{"x", 5}}, `x=5`},
 		// errors
 		{[]interface{}{5, "b"}, false},
 		{[]interface{}{"a", "b", "c"}, false},
+		{[]interface{}{[]string{"a", "b", "c"}}, false},
+		{[]interface{}{[]string{"a", "b"}, "c"}, false},
+		{[]interface{}{[]interface{}{"c", "d", "e"}}, false},
 	} {
 		errMsg := qt.Commentf("[%d] %v", i, test.params)
 
@@ -582,6 +589,32 @@ func TestQuerify(t *testing.T) {
 	}
 }
 
+func BenchmarkQuerify(b *testing.B) {
+	ns := New(&deps.Deps{})
+	params := []interface{}{"a", "b", "c", "d", "f", " &"}
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_, err := ns.Querify(params...)
+		if err != nil {
+			b.Fatal(err)
+		}
+	}
+}
+
+func BenchmarkQuerifySlice(b *testing.B) {
+	ns := New(&deps.Deps{})
+	params := []string{"a", "b", "c", "d", "f", " &"}
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_, err := ns.Querify(params)
+		if err != nil {
+			b.Fatal(err)
+		}
+	}
+}
+
 func TestSeq(t *testing.T) {
 	t.Parallel()
 	c := qt.New(t)