Triage the ignored test cases
diff --git a/tests/common/mod.rs b/tests/common/mod.rs
index 302cc5f..8e000f7 100644
--- a/tests/common/mod.rs
+++ b/tests/common/mod.rs
@@ -59,6 +59,7 @@
     // TODO assert that parsing fails on the parse-fail cases
     if path_string.starts_with("tests/rust/src/test/parse-fail")
         || path_string.starts_with("tests/rust/src/test/compile-fail")
+        || path_string.starts_with("tests/rust/src/test/rustfix")
     {
         return false;
     }
@@ -72,18 +73,24 @@
     }
 
     match path_string.as_ref() {
-        // TODO better support for attributes
+        // TODO outer attributes on literals
         //
-        //      { #![foo] }
-        "tests/rust/src/test/pretty/stmt_expr_attributes.rs" |
-        // TODO better support for attributes
+        //     #[noop] "Hello, world!"
+        //     #[cfg(unset)] 341
+        "tests/rust/src/test/run-pass-fulldeps/proc-macro/attr-stmt-expr.rs" |
         "tests/rust/src/test/run-pass/cfg_stmt_expr.rs" |
-        // TODO better support for attributes
+        // TODO outer attributes on closures
+        //
+        //     #[inline] || {}
+        "tests/rust/src/test/run-pass/issue-49632.rs" |
+        // TODO inner attributes within expressions
+        //
+        //     { #![foo] }
+        "tests/rust/src/test/pretty/stmt_expr_attributes.rs" |
+        // TODO inner attributes within blocks
+        //
+        //     fn test_fn_inner() { #![inner_fn_attr] }
         "tests/rust/src/test/run-pass/item-attributes.rs" |
-        // Deprecated placement syntax
-        "tests/rust/src/test/run-pass/new-box-syntax.rs" |
-        // Deprecated placement syntax
-        "tests/rust/src/test/run-pass/placement-in-syntax.rs" |
         // TODO inclusive range syntax
         "tests/rust/src/test/run-pass/range-inclusive-pattern-precedence.rs" |
         // TODO feature(extern_in_paths)
@@ -91,19 +98,31 @@
         //      use extern::xcrate;
         "tests/rust/src/test/run-make-fulldeps/save-analysis-rfc2126/extern_in_paths.rs" |
         "tests/rust/src/test/run-pass/rfc-2126-extern-absolute-paths/extern.rs" |
-        // TODO
-        "tests/rust/src/test/run-pass-fulldeps/proc-macro/attr-stmt-expr.rs" |
+        // TODO feature(macros_in_extern)
+        //
+        // https://github.com/dtolnay/syn/issues/390
         "tests/rust/src/test/run-pass-fulldeps/proc-macro/macros-in-extern.rs" |
-        "tests/rust/src/test/run-pass/async-await.rs" |
-        "tests/rust/src/test/run-pass/issue-49632.rs" |
-        "tests/rust/src/test/run-pass/label_break_value.rs" |
         "tests/rust/src/test/run-pass/macros-in-extern.rs" |
+        // TODO async closures and async functions
+        //
+        // https://github.com/dtolnay/syn/issues/396
+        // https://github.com/dtolnay/syn/issues/395
+        "tests/rust/src/test/run-pass/async-await.rs" |
+        // TODO feature(label_break_value)
+        //
+        //     'block: { break 'block "value" }
+        "tests/rust/src/test/run-pass/label_break_value.rs" |
+        // TODO unreserve pure, offsetof, sizeof, alignof
         "tests/rust/src/test/run-pass/rfc-2421-unreserve-pure-offsetof-sizeof-alignof.rs" |
-        "tests/rust/src/test/rustfix/missing-comma-in-match.rs" |
-        "tests/rust/src/test/rustfix/str-as-char.rs" |
-        "tests/rust/src/test/rustfix/tuple-float-index.rs" |
-        "tests/rust/src/test/ui/obsolete-in-place/bad.rs" |
+        // TODO where-clause on associated types
+        //
+        //     impl Foo for Bar {
+        //         type Assoc3<T> where T: Iterator = Vec<T>;
+        //     }
         "tests/rust/src/test/ui/rfc1598-generic-associated-types/generic-associated-types-where.rs" |
+        // Deprecated placement syntax
+        "tests/rust/src/test/run-pass/new-box-syntax.rs" |
+        "tests/rust/src/test/ui/obsolete-in-place/bad.rs" |
         // not actually test cases
         "tests/rust/src/test/run-pass/auxiliary/macro-comma-support.rs" |
         "tests/rust/src/test/run-pass/auxiliary/macro-include-items-expr.rs" => false,