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ef1114a964
The one notable test change is `tests/ui/macros/trace_faulty_macros.rs`. This commit removes the complicated `Interpolated` handling in `expected_expression_found` that results in a longer error message. But I think the new, shorter message is actually an improvement. The original complaint was in #71039, when the error message started with "error: expected expression, found `1 + 1`". That was confusing because `1 + 1` is an expression. Other than that, the reporter said "the whole error message is not too bad if you ignore the first line". Subsequently, extra complexity and wording was added to the error message. But I don't think the extra wording actually helps all that much. In particular, it still says of the `1+1` that "this is expected to be expression". This repeats the problem from the original complaint! This commit removes the extra complexity, reverting to a simpler error message. This is primarily because the traversal is a pain without `Interpolated` tokens. Nonetheless, I think the error message is *improved*. It now starts with "expected expression, found `pat` metavariable", which is much clearer and the real problem. It also doesn't say anything specific about `1+1`, which is good, because the `1+1` isn't really relevant to the error -- it's the `$e:pat` that's important.
55 lines
1023 B
Rust
55 lines
1023 B
Rust
//@ compile-flags: -Z trace-macros
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#![recursion_limit = "4"]
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macro_rules! my_faulty_macro {
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() => {
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my_faulty_macro!(bcd); //~ ERROR no rules
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};
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}
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macro_rules! pat_macro {
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() => {
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pat_macro!(A{a:a, b:0, c:_, ..});
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};
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($a:pat) => {
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$a //~ ERROR expected expression
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};
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}
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macro_rules! my_recursive_macro {
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() => {
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my_recursive_macro!(); //~ ERROR recursion limit
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};
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}
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macro_rules! my_macro {
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() => {};
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}
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fn main() {
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my_faulty_macro!();
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my_recursive_macro!();
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test!();
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non_exisiting!();
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derive!(Debug);
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let a = pat_macro!();
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}
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#[my_macro]
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fn use_bang_macro_as_attr() {}
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#[derive(Debug)] //~ ERROR `derive` may only be applied to `struct`s
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fn use_derive_macro_as_attr() {}
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macro_rules! test {
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(let $p:pat = $e:expr) => {test!(($p,$e))};
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// this should be expr
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// vvv
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(($p:pat, $e:pat)) => {let $p = $e;}; //~ ERROR expected expression, found `pat` metavariable
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}
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fn foo() {
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test!(let x = 1+1);
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}
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