1 files changed, 190 insertions, 0 deletions
diff --git a/tests/ui/macros/metavar-expressions/concat-usage-errors.rs b/tests/ui/macros/metavar-expressions/concat-usage-errors.rs
new file mode 100644
index 00000000000..7d8756de9e2
--- /dev/null
+++ b/tests/ui/macros/metavar-expressions/concat-usage-errors.rs
@@ -0,0 +1,190 @@
+//@ edition: 2021
+
+#![feature(macro_metavar_expr_concat)]
+
+macro_rules! syntax_errors {
+    ($ex:expr) => {
+        ${concat()}
+        //~^ ERROR expected identifier
+
+        ${concat(aaaa)}
+        //~^ ERROR `concat` must have at least two elements
+
+        ${concat(aaaa,)}
+        //~^ ERROR expected identifier
+
+        ${concat(_, aaaa)}
+
+        ${concat(aaaa aaaa)}
+        //~^ ERROR expected comma
+
+        ${concat($ex)}
+        //~^ ERROR `concat` must have at least two elements
+
+        ${concat($ex, aaaa)}
+        //~^ ERROR metavariables of `${concat(..)}` must be of type
+
+        ${concat($ex, aaaa 123)}
+        //~^ ERROR expected comma
+
+        ${concat($ex, aaaa,)}
+        //~^ ERROR expected identifier
+    };
+}
+
+macro_rules! dollar_sign_without_referenced_ident {
+    ($ident:ident) => {
+        const ${concat(FOO, $foo)}: i32 = 2;
+        //~^ ERROR variable `foo` is not recognized in meta-variable expression
+    };
+}
+
+macro_rules! starting_number {
+    ($ident:ident) => {{
+        let ${concat("1", $ident)}: () = ();
+        //~^ ERROR `${concat(..)}` is not generating a valid identifier
+    }};
+}
+
+macro_rules! starting_valid_unicode {
+    ($ident:ident) => {{
+        let ${concat("Ý", $ident)}: () = ();
+    }};
+}
+
+macro_rules! starting_invalid_unicode {
+    ($ident:ident) => {{
+        let ${concat("\u{00BD}", $ident)}: () = ();
+        //~^ ERROR `${concat(..)}` is not generating a valid identifier
+    }};
+}
+
+macro_rules! ending_number {
+    ($ident:ident) => {{
+        let ${concat($ident, "1")}: () = ();
+    }};
+}
+
+macro_rules! ending_valid_unicode {
+    ($ident:ident) => {{
+        let ${concat($ident, "Ý")}: () = ();
+    }};
+}
+
+macro_rules! ending_invalid_unicode {
+    ($ident:ident) => {{
+        let ${concat($ident, "\u{00BD}")}: () = ();
+        //~^ ERROR `${concat(..)}` is not generating a valid identifier
+    }};
+}
+
+macro_rules! empty {
+    () => {{
+        let ${concat("", "")}: () = ();
+        //~^ ERROR `${concat(..)}` is not generating a valid identifier
+    }};
+}
+
+macro_rules! unsupported_literals {
+    ($ident:ident) => {{
+        let ${concat(_a, 'b')}: () = ();
+        //~^ ERROR expected identifier or string literal
+        //~| ERROR expected pattern
+        let ${concat(_a, 1)}: () = ();
+        //~^ ERROR expected identifier or string literal
+        let ${concat(_a, 1.5)}: () = ();
+        //~^ ERROR expected identifier or string literal
+        let ${concat(_a, c"hi")}: () = ();
+        //~^ ERROR expected identifier or string literal
+        let ${concat(_a, b"hi")}: () = ();
+        //~^ ERROR expected identifier or string literal
+        let ${concat(_a, b'b')}: () = ();
+        //~^ ERROR expected identifier or string literal
+        let ${concat(_a, b'b')}: () = ();
+        //~^ ERROR expected identifier or string literal
+
+        let ${concat($ident, 'b')}: () = ();
+        //~^ ERROR expected identifier or string literal
+        let ${concat($ident, 1)}: () = ();
+        //~^ ERROR expected identifier or string literal
+        let ${concat($ident, 1.5)}: () = ();
+        //~^ ERROR expected identifier or string literal
+        let ${concat($ident, c"hi")}: () = ();
+        //~^ ERROR expected identifier or string literal
+        let ${concat($ident, b"hi")}: () = ();
+        //~^ ERROR expected identifier or string literal
+        let ${concat($ident, b'b')}: () = ();
+        //~^ ERROR expected identifier or string literal
+        let ${concat($ident, b'b')}: () = ();
+        //~^ ERROR expected identifier or string literal
+    }};
+}
+
+macro_rules! bad_literal_string {
+    ($literal:literal) => {
+        const ${concat(_foo, $literal)}: () = ();
+        //~^ ERROR `${concat(..)}` is not generating a valid identifier
+        //~| ERROR `${concat(..)}` is not generating a valid identifier
+        //~| ERROR `${concat(..)}` is not generating a valid identifier
+        //~| ERROR `${concat(..)}` is not generating a valid identifier
+        //~| ERROR `${concat(..)}` is not generating a valid identifier
+        //~| ERROR `${concat(..)}` is not generating a valid identifier
+        //~| ERROR `${concat(..)}` is not generating a valid identifier
+    }
+}
+
+macro_rules! bad_literal_non_string {
+    ($literal:literal) => {
+        const ${concat(_foo, $literal)}: () = ();
+        //~^ ERROR metavariables of `${concat(..)}` must be of type
+        //~| ERROR metavariables of `${concat(..)}` must be of type
+        //~| ERROR metavariables of `${concat(..)}` must be of type
+        //~| ERROR metavariables of `${concat(..)}` must be of type
+        //~| ERROR metavariables of `${concat(..)}` must be of type
+    }
+}
+
+macro_rules! bad_tt_literal {
+    ($tt:tt) => {
+        const ${concat(_foo, $tt)}: () = ();
+        //~^ ERROR metavariables of `${concat(..)}` must be of type
+        //~| ERROR metavariables of `${concat(..)}` must be of type
+        //~| ERROR metavariables of `${concat(..)}` must be of type
+    }
+}
+
+fn main() {
+    syntax_errors!(1);
+
+    dollar_sign_without_referenced_ident!(VAR);
+
+    starting_number!(_abc);
+    starting_valid_unicode!(_abc);
+    starting_invalid_unicode!(_abc);
+
+    ending_number!(_abc);
+    ending_valid_unicode!(_abc);
+    ending_invalid_unicode!(_abc);
+    unsupported_literals!(_abc);
+
+    empty!();
+
+    bad_literal_string!("\u{00BD}");
+    bad_literal_string!("\x41");
+    bad_literal_string!("🤷");
+    bad_literal_string!("d[-_-]b");
+
+    bad_literal_string!("-1");
+    bad_literal_string!("1.0");
+    bad_literal_string!("'1'");
+
+    bad_literal_non_string!(1);
+    bad_literal_non_string!(-1);
+    bad_literal_non_string!(1.0);
+    bad_literal_non_string!('1');
+    bad_literal_non_string!(false);
+
+    bad_tt_literal!(1);
+    bad_tt_literal!(1.0);
+    bad_tt_literal!('1');
+}