Resolve Foo::class parameter defaults to FQN in extract_parameters

Author: AJenbo

src/parser/ast_update.rs

@@ -246,11 +246,21 @@ impl Backend {
         // like `if (! function_exists('...'))`) using the shared helper
         // which recurses into if/block statements.
         let mut functions = Vec::new();
+        // Update doc_ctx with the file's use-map and namespace so that
+        // parameter default values (e.g. `Application::class`) can be
+        // resolved to FQNs during extraction.
+        let func_doc_ctx = DocblockCtx {
+            trivias: doc_ctx.trivias,
+            content: doc_ctx.content,
+            php_version: doc_ctx.php_version,
+            use_map: use_map.clone(),
+            namespace: namespace.clone(),
+        };
         Self::extract_functions_from_statements(
             program.statements.iter(),
             &mut functions,
             &namespace,
-            Some(&doc_ctx),
+            Some(&func_doc_ctx),
         );
         if !functions.is_empty() {
             // Resolve class-like names in function return types and

src/parser/mod.rs

@@ -938,7 +938,15 @@ pub(crate) fn extract_parameters(
                 let span = dv.value.span();
                 let start = span.start.offset as usize;
                 let end = span.end.offset as usize;
-                src.get(start..end).map(|s| s.trim().to_string())
+                let raw = src.get(start..end)?.trim().to_string();
+                // Resolve `ClassName::class` to its FQN so that
+                // downstream template substitution can find the class.
+                if let Some(class_name) = raw.strip_suffix("::class") {
+                    let fqn = resolve_default_class_name(class_name, doc_ctx);
+                    Some(format!("{}::class", fqn))
+                } else {
+                    Some(raw)
+                }
             });
 
             ParameterInfo {
@@ -956,6 +964,35 @@ pub(crate) fn extract_parameters(
         .collect()
 }
 
+/// Resolve a class name from a parameter default (`Foo::class`) to its FQN
+/// using the file's use-map and namespace from [`DocblockCtx`].
+fn resolve_default_class_name(name: &str, doc_ctx: Option<&DocblockCtx<'_>>) -> String {
+    // Already fully-qualified.
+    if let Some(stripped) = name.strip_prefix('\\') {
+        return stripped.to_string();
+    }
+    let Some(ctx) = doc_ctx else {
+        return name.to_string();
+    };
+    // Check use-map (handles `use App\Application;` → "Application" → "App\Application").
+    if let Some(fqn) = ctx.use_map.get(name) {
+        return fqn.clone();
+    }
+    // If the name has a namespace prefix (e.g. `Sub\Foo`), check the first segment.
+    if let Some(first_seg) = name.split('\\').next()
+        && first_seg != name
+        && let Some(base) = ctx.use_map.get(first_seg)
+    {
+        let rest = &name[first_seg.len() + 1..];
+        return format!("{}\\{}", base, rest);
+    }
+    // Prepend file namespace if present.
+    if let Some(ref ns) = ctx.namespace {
+        return format!("{}\\{}", ns, name);
+    }
+    name.to_string()
+}
+
 /// Extract visibility from a set of modifiers.
 /// Defaults to `Public` if no visibility modifier is present.
 pub(crate) fn extract_visibility<'a>(

tests/integration/completion_generics.rs

@@ -5019,11 +5019,20 @@ async fn test_method_template_self_class_resolves_to_enclosing_class() {
     backend.did_open(open_params).await;
 
     let line = text.lines().position(|l| l.contains("$child->")).unwrap() as u32;
-    let col = text.lines().nth(line as usize).unwrap().find("$child->").unwrap() as u32 + 8;
+    let col = text
+        .lines()
+        .nth(line as usize)
+        .unwrap()
+        .find("$child->")
+        .unwrap() as u32
+        + 8;
     let completion_params = CompletionParams {
         text_document_position: TextDocumentPositionParams {
             text_document: TextDocumentIdentifier { uri },
-            position: Position { line, character: col },
+            position: Position {
+                line,
+                character: col,
+            },
         },
         work_done_progress_params: Default::default(),
         partial_result_params: Default::default(),