tests: adding classes to an elementHEADmain

Signed-off-by: Lars Wirzenius <liw@liw.fi>
Sponsored-by: author

1 files changed, 33 insertions, 2 deletions

diff --git a/src/lib.rs b/src/lib.rs
index 51baa99..ab5cb84 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -530,10 +530,12 @@ impl Element {
     /// classes.
     pub fn add_class(&mut self, class: &str) {
         if let Some(old) = self.attribute_value("class") {
-            self.set_attribute("class", &format!("{old} {class}"));
+            if !old.split_ascii_whitespace().any(|s| s == class) {
+                self.set_attribute("class", &format!("{old} {class}"));
+            }
         } else {
             self.set_attribute("class", class);
-        };
+        }
     }
 
     /// Append text to element. It will be escaped, if needed, when
@@ -754,6 +756,35 @@ mod test {
     }
 
     #[test]
+    fn can_add_class_to_element() {
+        let mut e = Element::new(Tag::P);
+        e.add_class("foo");
+        let classes: Vec<&str> = e.classes().collect();
+        assert_eq!(classes, ["foo"]);
+        assert_eq!(e.to_string(), r#"<P class="foo"/>"#);
+    }
+
+    #[test]
+    fn can_two_classes_to_element() {
+        let mut e = Element::new(Tag::P);
+        e.add_class("foo");
+        e.add_class("bar");
+        let classes: Vec<&str> = e.classes().collect();
+        assert_eq!(classes, ["foo", "bar"]);
+        assert_eq!(e.to_string(), r#"<P class="foo bar"/>"#);
+    }
+
+    #[test]
+    fn can_add_same_class_twice_to_element() {
+        let mut e = Element::new(Tag::P);
+        e.add_class("foo");
+        e.add_class("foo");
+        let classes: Vec<&str> = e.classes().collect();
+        assert_eq!(classes, ["foo"]);
+        assert_eq!(e.to_string(), r#"<P class="foo"/>"#);
+    }
+
+    #[test]
     fn can_add_boolean_attribute_to_element() {
         let mut e = Element::new(Tag::P);
         e.set_boolean_attribute("foo");