parse unsafe extern blocks and safe fns / static items

Author: m4rch3n1ng

grammar.js

@@ -280,6 +280,7 @@ module.exports = grammar({
 
     foreign_mod_item: $ => seq(
       optional($.visibility_modifier),
+      optional($._item_modifiers),
       $.extern_modifier,
       choice(
         ';',
@@ -404,6 +405,7 @@ module.exports = grammar({
 
     static_item: $ => seq(
       optional($.visibility_modifier),
+      optional(choice('unsafe', 'safe')),
       'static',
 
       // Not actual rust syntax, but made popular by the lazy_static crate.
@@ -456,12 +458,21 @@ module.exports = grammar({
       ';',
     ),
 
-    function_modifiers: $ => repeat1(choice(
+    function_modifiers: $ => choice(
+      $._item_modifiers,
+      $.extern_modifier,
+      seq(
+        $._item_modifiers,
+        $.extern_modifier,
+      )
+    ),
+
+    _item_modifiers: _ => repeat1(choice(
       'async',
       'default',
       'const',
       'unsafe',
-      $.extern_modifier,
+      'safe',
     )),
 
     where_clause: $ => prec.right(seq(

test/corpus/declarations.txt

@@ -2613,3 +2613,65 @@ pub struct Loaf<T: Sized, const N: usize = 1>([T; N]);
       (array_type
         (type_identifier)
         (identifier)))))
+
+================================================================================
+Unsafe extern blocks
+================================================================================
+
+unsafe extern "C" {
+    pub safe fn sqrt(x: f64) -> f64;
+    pub unsafe fn strlen(p: *const std::ffi::c_char) -> usize;
+    pub fn free(p: *mut core::ffi::c_void);
+    pub safe static IMPORTANT_BYTES: [u8; 256];
+}
+
+--------------------------------------------------------------------------------
+
+(source_file
+  (foreign_mod_item
+    (extern_modifier
+      (string_literal
+        (string_content)))
+    (declaration_list
+      (function_signature_item
+        (visibility_modifier)
+        (function_modifiers)
+        (identifier)
+        (parameters
+          (parameter
+            (identifier)
+            (primitive_type)))
+        (primitive_type))
+      (function_signature_item
+        (visibility_modifier)
+        (function_modifiers)
+        (identifier)
+        (parameters
+          (parameter
+            (identifier)
+            (pointer_type
+              (scoped_type_identifier
+                (scoped_identifier
+                  (identifier)
+                  (identifier))
+                (type_identifier)))))
+        (primitive_type))
+      (function_signature_item
+        (visibility_modifier)
+        (identifier)
+        (parameters
+          (parameter
+            (identifier)
+            (pointer_type
+              (mutable_specifier)
+              (scoped_type_identifier
+                (scoped_identifier
+                  (identifier)
+                  (identifier))
+                (type_identifier))))))
+      (static_item
+        (visibility_modifier)
+        (identifier)
+        (array_type
+          (primitive_type)
+          (integer_literal))))))