Implement console.count/countReset (#31635)

* Implement console.count/countReset

* Address review comment

Signed-off-by: syvb <me@iter.ca>

---------

Signed-off-by: syvb <me@iter.ca>

3 files changed, 46 insertions, 0 deletions

diff --git a/components/script/dom/console.rs b/components/script/dom/console.rs
index f8547c449ff..737bb35b926 100644
--- a/components/script/dom/console.rs
+++ b/components/script/dom/console.rs
@@ -296,4 +296,21 @@ impl Console {
     pub fn GroupEnd(global: &GlobalScope) {
         global.pop_console_group();
     }
+
+    /// <https://console.spec.whatwg.org/#count>
+    pub fn Count(global: &GlobalScope, label: DOMString) {
+        let count = global.increment_console_count(&label);
+        let message = DOMString::from(format!("{label}: {count}"));
+        console_message(global, message, LogLevel::Log);
+    }
+
+    /// <https://console.spec.whatwg.org/#countreset>
+    pub fn CountReset(global: &GlobalScope, label: DOMString) {
+        if global.reset_console_count(&label).is_err() {
+            Self::internal_warn(
+                global,
+                DOMString::from(format!("Counter “{label}” doesn’t exist.")),
+            )
+        }
+    }
 }
diff --git a/components/script/dom/globalscope.rs b/components/script/dom/globalscope.rs
index c9fd013318c..9140088f67d 100644
--- a/components/script/dom/globalscope.rs
+++ b/components/script/dom/globalscope.rs
@@ -329,6 +329,11 @@ pub struct GlobalScope {
     /// The stack of active group labels for the Console APIs.
     console_group_stack: DomRefCell<Vec<DOMString>>,
 
+    /// The count map for the Console APIs.
+    ///
+    /// <https://console.spec.whatwg.org/#count>
+    console_count_map: DomRefCell<HashMap<DOMString, usize>>,
+
     /// List of ongoing dynamic module imports.
     dynamic_modules: DomRefCell<DynamicModuleList>,
 
@@ -790,6 +795,7 @@ impl GlobalScope {
             frozen_supported_performance_entry_types: DomRefCell::new(Default::default()),
             https_state: Cell::new(HttpsState::None),
             console_group_stack: DomRefCell::new(Vec::new()),
+            console_count_map: Default::default(),
             dynamic_modules: DomRefCell::new(DynamicModuleList::new()),
             inherited_secure_context,
         }
@@ -3255,6 +3261,25 @@ impl GlobalScope {
         let _ = self.console_group_stack.borrow_mut().pop();
     }
 
+    pub(crate) fn increment_console_count(&self, label: &DOMString) -> usize {
+        *self
+            .console_count_map
+            .borrow_mut()
+            .entry(label.clone())
+            .and_modify(|e| *e += 1)
+            .or_insert(1)
+    }
+
+    pub(crate) fn reset_console_count(&self, label: &DOMString) -> Result<(), ()> {
+        match self.console_count_map.borrow_mut().get_mut(label) {
+            Some(value) => {
+                *value = 0;
+                Ok(())
+            },
+            None => Err(()),
+        }
+    }
+
     pub(crate) fn dynamic_module_list(&self) -> RefMut<DynamicModuleList> {
         self.dynamic_modules.borrow_mut()
     }
diff --git a/components/script/dom/webidls/Console.webidl b/components/script/dom/webidls/Console.webidl
index ac6ffa27806..4cc02d80436 100644
--- a/components/script/dom/webidls/Console.webidl
+++ b/components/script/dom/webidls/Console.webidl
@@ -17,6 +17,10 @@ namespace console {
   undefined assert(boolean condition, optional any message);
   undefined clear();
 
+  // Counting
+  undefined count(optional DOMString label = "default");
+  undefined countReset(optional DOMString label = "default");
+
   // Grouping
   undefined group(any... data);
   undefined groupCollapsed(any... data);