feat: hash_map macro

Author: stifskere

library/alloc/src/macros.rs

@@ -109,3 +109,18 @@ macro_rules! format {
         })
     }
 }
+
+#[macro_export]
+#[allow_internal_unstable(hint_must_use)]
+#[rustc_diagnostic_item = "hash_map_macro"]
+macro_rules! hash_map {
+    () => {{
+        ::std::collections::HashMap::new()
+    }};
+
+    ( $( $key:expr => $value:expr ),* $(,)? ) => {{
+        let mut __map = ::std::collections::HashMap::new();
+        $( __map.insert($key, $value); )*
+        __map
+    }}
+}