1 files changed, 303 insertions, 0 deletions
diff --git a/third_party/rust/thiserror/tests/test_display.rs b/third_party/rust/thiserror/tests/test_display.rs
new file mode 100644
index 0000000000..6f603882eb
--- /dev/null
+++ b/third_party/rust/thiserror/tests/test_display.rs
@@ -0,0 +1,303 @@
+#![allow(clippy::uninlined_format_args)]
+
+use std::fmt::{self, Display};
+use thiserror::Error;
+
+fn assert<T: Display>(expected: &str, value: T) {
+    assert_eq!(expected, value.to_string());
+}
+
+#[test]
+fn test_braced() {
+    #[derive(Error, Debug)]
+    #[error("braced error: {msg}")]
+    struct Error {
+        msg: String,
+    }
+
+    let msg = "T".to_owned();
+    assert("braced error: T", Error { msg });
+}
+
+#[test]
+fn test_braced_unused() {
+    #[derive(Error, Debug)]
+    #[error("braced error")]
+    struct Error {
+        extra: usize,
+    }
+
+    assert("braced error", Error { extra: 0 });
+}
+
+#[test]
+fn test_tuple() {
+    #[derive(Error, Debug)]
+    #[error("tuple error: {0}")]
+    struct Error(usize);
+
+    assert("tuple error: 0", Error(0));
+}
+
+#[test]
+fn test_unit() {
+    #[derive(Error, Debug)]
+    #[error("unit error")]
+    struct Error;
+
+    assert("unit error", Error);
+}
+
+#[test]
+fn test_enum() {
+    #[derive(Error, Debug)]
+    enum Error {
+        #[error("braced error: {id}")]
+        Braced { id: usize },
+        #[error("tuple error: {0}")]
+        Tuple(usize),
+        #[error("unit error")]
+        Unit,
+    }
+
+    assert("braced error: 0", Error::Braced { id: 0 });
+    assert("tuple error: 0", Error::Tuple(0));
+    assert("unit error", Error::Unit);
+}
+
+#[test]
+fn test_constants() {
+    #[derive(Error, Debug)]
+    #[error("{MSG}: {id:?} (code {CODE:?})")]
+    struct Error {
+        id: &'static str,
+    }
+
+    const MSG: &str = "failed to do";
+    const CODE: usize = 9;
+
+    assert("failed to do: \"\" (code 9)", Error { id: "" });
+}
+
+#[test]
+fn test_inherit() {
+    #[derive(Error, Debug)]
+    #[error("{0}")]
+    enum Error {
+        Some(&'static str),
+        #[error("other error")]
+        Other(&'static str),
+    }
+
+    assert("some error", Error::Some("some error"));
+    assert("other error", Error::Other("..."));
+}
+
+#[test]
+fn test_brace_escape() {
+    #[derive(Error, Debug)]
+    #[error("fn main() {{}}")]
+    struct Error;
+
+    assert("fn main() {}", Error);
+}
+
+#[test]
+fn test_expr() {
+    #[derive(Error, Debug)]
+    #[error("1 + 1 = {}", 1 + 1)]
+    struct Error;
+    assert("1 + 1 = 2", Error);
+}
+
+#[test]
+fn test_nested() {
+    #[derive(Error, Debug)]
+    #[error("!bool = {}", not(.0))]
+    struct Error(bool);
+
+    #[allow(clippy::trivially_copy_pass_by_ref)]
+    fn not(bool: &bool) -> bool {
+        !*bool
+    }
+
+    assert("!bool = false", Error(true));
+}
+
+#[test]
+fn test_match() {
+    #[derive(Error, Debug)]
+    #[error("{}: {0}", match .1 {
+        Some(n) => format!("error occurred with {}", n),
+        None => "there was an empty error".to_owned(),
+    })]
+    struct Error(String, Option<usize>);
+
+    assert(
+        "error occurred with 1: ...",
+        Error("...".to_owned(), Some(1)),
+    );
+    assert(
+        "there was an empty error: ...",
+        Error("...".to_owned(), None),
+    );
+}
+
+#[test]
+fn test_nested_display() {
+    // Same behavior as the one in `test_match`, but without String allocations.
+    #[derive(Error, Debug)]
+    #[error("{}", {
+        struct Msg<'a>(&'a String, &'a Option<usize>);
+        impl<'a> Display for Msg<'a> {
+            fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+                match self.1 {
+                    Some(n) => write!(formatter, "error occurred with {}", n),
+                    None => write!(formatter, "there was an empty error"),
+                }?;
+                write!(formatter, ": {}", self.0)
+            }
+        }
+        Msg(.0, .1)
+    })]
+    struct Error(String, Option<usize>);
+
+    assert(
+        "error occurred with 1: ...",
+        Error("...".to_owned(), Some(1)),
+    );
+    assert(
+        "there was an empty error: ...",
+        Error("...".to_owned(), None),
+    );
+}
+
+#[test]
+fn test_void() {
+    #[allow(clippy::empty_enum)]
+    #[derive(Error, Debug)]
+    #[error("...")]
+    pub enum Error {}
+
+    let _: Error;
+}
+
+#[test]
+fn test_mixed() {
+    #[derive(Error, Debug)]
+    #[error("a={a} :: b={} :: c={c} :: d={d}", 1, c = 2, d = 3)]
+    struct Error {
+        a: usize,
+        d: usize,
+    }
+
+    assert("a=0 :: b=1 :: c=2 :: d=3", Error { a: 0, d: 0 });
+}
+
+#[test]
+fn test_ints() {
+    #[derive(Error, Debug)]
+    enum Error {
+        #[error("error {0}")]
+        Tuple(usize, usize),
+        #[error("error {0}", '?')]
+        Struct { v: usize },
+    }
+
+    assert("error 9", Error::Tuple(9, 0));
+    assert("error ?", Error::Struct { v: 0 });
+}
+
+#[test]
+fn test_trailing_comma() {
+    #[derive(Error, Debug)]
+    #[error(
+        "error {0}",
+    )]
+    #[rustfmt::skip]
+    struct Error(char);
+
+    assert("error ?", Error('?'));
+}
+
+#[test]
+fn test_field() {
+    #[derive(Debug)]
+    struct Inner {
+        data: usize,
+    }
+
+    #[derive(Error, Debug)]
+    #[error("{}", .0.data)]
+    struct Error(Inner);
+
+    assert("0", Error(Inner { data: 0 }));
+}
+
+#[test]
+fn test_macro_rules() {
+    // Regression test for https://github.com/dtolnay/thiserror/issues/86
+
+    macro_rules! decl_error {
+        ($variant:ident($value:ident)) => {
+            #[derive(Debug, Error)]
+            pub enum Error0 {
+                #[error("{0:?}")]
+                $variant($value),
+            }
+
+            #[derive(Debug, Error)]
+            #[error("{0:?}")]
+            pub enum Error1 {
+                $variant($value),
+            }
+        };
+    }
+
+    decl_error!(Repro(u8));
+
+    assert("0", Error0::Repro(0));
+    assert("0", Error1::Repro(0));
+}
+
+#[test]
+fn test_raw() {
+    #[derive(Error, Debug)]
+    #[error("braced raw error: {r#fn}")]
+    struct Error {
+        r#fn: &'static str,
+    }
+
+    assert("braced raw error: T", Error { r#fn: "T" });
+}
+
+#[test]
+fn test_raw_enum() {
+    #[derive(Error, Debug)]
+    enum Error {
+        #[error("braced raw error: {r#fn}")]
+        Braced { r#fn: &'static str },
+    }
+
+    assert("braced raw error: T", Error::Braced { r#fn: "T" });
+}
+
+#[test]
+fn test_raw_conflict() {
+    #[derive(Error, Debug)]
+    enum Error {
+        #[error("braced raw error: {r#func}, {func}", func = "U")]
+        Braced { r#func: &'static str },
+    }
+
+    assert("braced raw error: T, U", Error::Braced { r#func: "T" });
+}
+
+#[test]
+fn test_keyword() {
+    #[derive(Error, Debug)]
+    #[error("error: {type}", type = 1)]
+    struct Error;
+
+    assert("error: 1", Error);
+}