feat: manipulate classes0.1.0

Sponsored-by: author

1 files changed, 65 insertions, 0 deletions

diff --git a/src/lib.rs b/src/lib.rs
index 8df262e..331c09b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -462,6 +462,12 @@ impl Element {
         self
     }
 
+    /// Add a class when creating an element.
+    pub fn with_class(mut self, class: &str) -> Self {
+        self.add_class(class);
+        self
+    }
+
     /// Return the [`Tag`] of the element.
     pub fn tag(&self) -> Tag {
         self.tag
@@ -505,6 +511,31 @@ impl Element {
         self.attrs.unset(name);
     }
 
+    /// Return current classes set directly for this element.
+    pub fn classes(&self) -> impl Iterator<Item = &str> {
+        let v = if let Some(v) = self.attribute_value("class") {
+            v
+        } else {
+            ""
+        };
+        v.split_ascii_whitespace()
+    }
+
+    /// Does the element have a class set directly?
+    pub fn has_class(&self, wanted: &str) -> bool {
+        self.classes().any(|v| v == wanted)
+    }
+
+    /// Add a class to the element. This does not replace existing
+    /// classes.
+    pub fn add_class(&mut self, class: &str) {
+        if let Some(old) = self.attribute_value("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
     /// the element is serialized.
     pub fn push_text(&mut self, text: &str) {
@@ -811,6 +842,40 @@ mod test {
         assert_eq!(e.serialize(), "<P>hello &lt;world&gt;</P>");
     }
 
+    #[test]
+    fn element_has_no_class_initially() {
+        let e = Element::new(Tag::P);
+        assert_eq!(e.attribute_value("class"), None);
+        assert_eq!(e.classes().next(), None);
+        assert!(!e.has_class("foo"));
+    }
+
+    #[test]
+    fn element_adds_first_class() {
+        let mut e = Element::new(Tag::P);
+        e.add_class("foo");
+        assert_eq!(e.attribute_value("class"), Some("foo"));
+        assert!(e.has_class("foo"));
+    }
+
+    #[test]
+    fn element_adds_second_class() {
+        let mut e = Element::new(Tag::P);
+        e.add_class("foo");
+        e.add_class("bar");
+        assert_eq!(e.attribute_value("class"), Some("foo bar"));
+        assert!(e.has_class("foo"));
+        assert!(e.has_class("bar"));
+    }
+
+    #[test]
+    fn creates_classy_element() {
+        let e = Element::new(Tag::P).with_class("foo").with_class("bar");
+        assert_eq!(e.attribute_value("class"), Some("foo bar"));
+        assert!(e.has_class("foo"));
+        assert!(e.has_class("bar"));
+    }
+
     #[derive(Default)]
     struct Collector {
         tags: Vec<Tag>,