diff options
5 files changed, 39 insertions, 9 deletions
diff --git a/compiler/rustc_expand/src/mbe/transcribe.rs b/compiler/rustc_expand/src/mbe/transcribe.rs index fdd8dc93fc1..3037855ae28 100644 --- a/compiler/rustc_expand/src/mbe/transcribe.rs +++ b/compiler/rustc_expand/src/mbe/transcribe.rs @@ -512,7 +512,18 @@ fn out_of_bounds_err<'a>( span: Span, ty: &str, ) -> DiagnosticBuilder<'a, ErrorGuaranteed> { - cx.struct_span_err(span, &format!("{ty} depth must be less than {max}")) + let msg = if max == 0 { + format!( + "meta-variable expression `{ty}` with depth parameter \ + must be called inside of a macro repetition" + ) + } else { + format!( + "depth parameter on meta-variable expression `{ty}` \ + must be less than {max}" + ) + }; + cx.struct_span_err(span, &msg) } fn transcribe_metavar_expr<'a>( diff --git a/src/test/ui/macros/meta-variable-depth-outside-repeat.rs b/src/test/ui/macros/meta-variable-depth-outside-repeat.rs new file mode 100644 index 00000000000..b7fb947854f --- /dev/null +++ b/src/test/ui/macros/meta-variable-depth-outside-repeat.rs @@ -0,0 +1,12 @@ +#![feature(macro_metavar_expr)] + +macro_rules! metavar { + ( $i:expr ) => { + ${length(0)} + //~^ ERROR meta-variable expression `length` with depth parameter must be called inside of a macro repetition + }; +} + +const _: i32 = metavar!(0); + +fn main() {} diff --git a/src/test/ui/macros/meta-variable-depth-outside-repeat.stderr b/src/test/ui/macros/meta-variable-depth-outside-repeat.stderr new file mode 100644 index 00000000000..fad150cadfc --- /dev/null +++ b/src/test/ui/macros/meta-variable-depth-outside-repeat.stderr @@ -0,0 +1,8 @@ +error: meta-variable expression `length` with depth parameter must be called inside of a macro repetition + --> $DIR/meta-variable-depth-outside-repeat.rs:5:10 + | +LL | ${length(0)} + | ^^^^^^^^^^^ + +error: aborting due to previous error + diff --git a/src/test/ui/macros/rfc-3086-metavar-expr/out-of-bounds-arguments.rs b/src/test/ui/macros/rfc-3086-metavar-expr/out-of-bounds-arguments.rs index d81c8628bab..6a0d68bd6b1 100644 --- a/src/test/ui/macros/rfc-3086-metavar-expr/out-of-bounds-arguments.rs +++ b/src/test/ui/macros/rfc-3086-metavar-expr/out-of-bounds-arguments.rs @@ -5,7 +5,7 @@ macro_rules! a { ( ${count(foo, 0)}, ${count(foo, 10)}, - //~^ ERROR count depth must be less than 4 + //~^ ERROR depth parameter on meta-variable expression `count` must be less than 4 ) }; } @@ -17,7 +17,7 @@ macro_rules! b { ${ignore(foo)} ${index(0)}, ${index(10)}, - //~^ ERROR index depth must be less than 3 + //~^ ERROR depth parameter on meta-variable expression `index` must be less than 3 )* )* )* ) }; @@ -30,15 +30,14 @@ macro_rules! c { ${ignore(foo)} ${length(0)} ${length(10)} - //~^ ERROR length depth must be less than 2 + //~^ ERROR depth parameter on meta-variable expression `length` must be less than 2 )* )* ) }; } - fn main() { a!( { [ (a) ] [ (b c) ] } ); b!( { [ a b ] } ); - c!( { a } ); + c!({ a }); } diff --git a/src/test/ui/macros/rfc-3086-metavar-expr/out-of-bounds-arguments.stderr b/src/test/ui/macros/rfc-3086-metavar-expr/out-of-bounds-arguments.stderr index 7474c03c0f9..236122b6465 100644 --- a/src/test/ui/macros/rfc-3086-metavar-expr/out-of-bounds-arguments.stderr +++ b/src/test/ui/macros/rfc-3086-metavar-expr/out-of-bounds-arguments.stderr @@ -1,16 +1,16 @@ -error: count depth must be less than 4 +error: depth parameter on meta-variable expression `count` must be less than 4 --> $DIR/out-of-bounds-arguments.rs:7:14 | LL | ${count(foo, 10)}, | ^^^^^^^^^^^^^^^^ -error: index depth must be less than 3 +error: depth parameter on meta-variable expression `index` must be less than 3 --> $DIR/out-of-bounds-arguments.rs:19:18 | LL | ${index(10)}, | ^^^^^^^^^^^ -error: length depth must be less than 2 +error: depth parameter on meta-variable expression `length` must be less than 2 --> $DIR/out-of-bounds-arguments.rs:32:18 | LL | ${length(10)} |