1 files changed, 102 insertions, 0 deletions
diff --git a/tests/ui/macros/metavar-expressions/macro-expansion.rs b/tests/ui/macros/metavar-expressions/macro-expansion.rs
new file mode 100644
index 00000000000..1d34275874b
--- /dev/null
+++ b/tests/ui/macros/metavar-expressions/macro-expansion.rs
@@ -0,0 +1,102 @@
+//@ run-pass
+
+#![feature(macro_metavar_expr)]
+
+#[derive(Debug)]
+struct Example<'a> {
+    _indexes: &'a [(u32, u32)],
+    _counts: &'a [u32],
+    _nested: Vec<Example<'a>>,
+}
+
+macro_rules! example {
+    ( $( [ $( ( $( $x:ident )* ) )* ] )* ) => {
+        Example {
+            _indexes: &[],
+            _counts: &[${count($x, 0)}, ${count($x, 1)}, ${count($x, 2)}],
+            _nested: vec![
+            $(
+                Example {
+                    _indexes: &[(${index()}, ${len()})],
+                    _counts: &[${count($x, 0)}, ${count($x, 1)}],
+                    _nested: vec![
+                    $(
+                        Example {
+                            _indexes: &[(${index(1)}, ${len(1)}), (${index()}, ${len()})],
+                            _counts: &[${count($x)}],
+                            _nested: vec![
+                            $(
+                                Example {
+                                    _indexes: &[
+                                        (${index(2)}, ${len(2)}),
+                                        (${index(1)}, ${len(1)}),
+                                        (${index()}, ${len()})
+                                    ],
+                                    _counts: &[],
+                                    _nested: vec![],
+                                    ${ignore($x)}
+                                }
+                            ),*
+                            ]
+                        }
+                    ),*
+                    ]
+                }
+            ),*
+            ]
+        }
+    };
+}
+
+static EXPECTED: &str = concat!(
+    "Example { _indexes: [], _counts: [13, 4, 2], _nested: [",
+    concat!(
+        "Example { _indexes: [(0, 2)], _counts: [10, 3], _nested: [",
+        concat!(
+            "Example { _indexes: [(0, 2), (0, 3)], _counts: [4], _nested: [",
+            concat!(
+                "Example { _indexes: [(0, 2), (0, 3), (0, 4)], _counts: [], _nested: [] }, ",
+                "Example { _indexes: [(0, 2), (0, 3), (1, 4)], _counts: [], _nested: [] }, ",
+                "Example { _indexes: [(0, 2), (0, 3), (2, 4)], _counts: [], _nested: [] }, ",
+                "Example { _indexes: [(0, 2), (0, 3), (3, 4)], _counts: [], _nested: [] }",
+            ),
+            "] }, ",
+            "Example { _indexes: [(0, 2), (1, 3)], _counts: [4], _nested: [",
+            concat!(
+                "Example { _indexes: [(0, 2), (1, 3), (0, 4)], _counts: [], _nested: [] }, ",
+                "Example { _indexes: [(0, 2), (1, 3), (1, 4)], _counts: [], _nested: [] }, ",
+                "Example { _indexes: [(0, 2), (1, 3), (2, 4)], _counts: [], _nested: [] }, ",
+                "Example { _indexes: [(0, 2), (1, 3), (3, 4)], _counts: [], _nested: [] }",
+            ),
+            "] }, ",
+            "Example { _indexes: [(0, 2), (2, 3)], _counts: [2], _nested: [",
+            concat!(
+                "Example { _indexes: [(0, 2), (2, 3), (0, 2)], _counts: [], _nested: [] }, ",
+                "Example { _indexes: [(0, 2), (2, 3), (1, 2)], _counts: [], _nested: [] }",
+            ),
+            "] }",
+        ),
+        "] }, ",
+        "Example { _indexes: [(1, 2)], _counts: [3, 1], _nested: [",
+        concat!(
+            "Example { _indexes: [(1, 2), (0, 1)], _counts: [3], _nested: [",
+            concat!(
+                "Example { _indexes: [(1, 2), (0, 1), (0, 3)], _counts: [], _nested: [] }, ",
+                "Example { _indexes: [(1, 2), (0, 1), (1, 3)], _counts: [], _nested: [] }, ",
+                "Example { _indexes: [(1, 2), (0, 1), (2, 3)], _counts: [], _nested: [] }",
+            ),
+            "] }",
+        ),
+        "] }",
+    ),
+    "] }",
+);
+
+fn main() {
+    let e = example! {
+        [ ( A B C D ) ( E F G H ) ( I J ) ]
+        [ ( K L M ) ]
+    };
+    let debug = format!("{:?}", e);
+    assert_eq!(debug, EXPECTED);
+}