diff --git a/crates/hir-def/src/macro_expansion_tests/proc_macros.rs b/crates/hir-def/src/macro_expansion_tests/proc_macros.rs index 70e3e1ed4e..a43c0eb9d7 100644 --- a/crates/hir-def/src/macro_expansion_tests/proc_macros.rs +++ b/crates/hir-def/src/macro_expansion_tests/proc_macros.rs @@ -5,7 +5,7 @@ //! in-memory macros. use expect_test::expect; -use crate::macro_expansion_tests::check; +use crate::macro_expansion_tests::{check, check_errors}; #[test] fn attribute_macro_attr_censoring() { @@ -216,3 +216,21 @@ struct S; #[doc = "doc attr"] struct S;"##]], ); } + +#[test] +fn cfg_evaluated_before_attr_macros() { + check_errors( + r#" +//- proc_macros: disallow_cfg + +use proc_macros::disallow_cfg; + +#[disallow_cfg] #[cfg(false)] fn foo() {} +// True cfg are kept. +// #[disallow_cfg] #[cfg(true)] fn bar() {} +#[disallow_cfg] #[cfg_attr(false, inline)] fn baz() {} +#[disallow_cfg] #[cfg_attr(true, inline)] fn qux() {} + "#, + expect![[r#""#]], + ); +} diff --git a/crates/hir-expand/src/cfg_process.rs b/crates/hir-expand/src/cfg_process.rs index 01a3103af8..626a82ae08 100644 --- a/crates/hir-expand/src/cfg_process.rs +++ b/crates/hir-expand/src/cfg_process.rs @@ -201,9 +201,6 @@ pub(crate) fn process_cfg_attrs( MacroDefKind::BuiltInAttr(_, expander) => expander.is_derive(), _ => false, }; - if !is_derive { - return None; - } let mut remove = FxHashSet::default(); let item = ast::Item::cast(node.clone())?; @@ -220,28 +217,43 @@ pub(crate) fn process_cfg_attrs( } } } - match item { - ast::Item::Struct(it) => match it.field_list()? { - ast::FieldList::RecordFieldList(fields) => { - process_has_attrs_with_possible_comma(db, fields.fields(), loc.krate, &mut remove)?; + + if is_derive { + // Only derives get their code cfg-clean, normal attribute macros process only the cfg at their level + // (cfg_attr is handled above, cfg is handled in the def map). + match item { + ast::Item::Struct(it) => match it.field_list()? { + ast::FieldList::RecordFieldList(fields) => { + process_has_attrs_with_possible_comma( + db, + fields.fields(), + loc.krate, + &mut remove, + )?; + } + ast::FieldList::TupleFieldList(fields) => { + process_has_attrs_with_possible_comma( + db, + fields.fields(), + loc.krate, + &mut remove, + )?; + } + }, + ast::Item::Enum(it) => { + process_enum(db, it.variant_list()?, loc.krate, &mut remove)?; } - ast::FieldList::TupleFieldList(fields) => { - process_has_attrs_with_possible_comma(db, fields.fields(), loc.krate, &mut remove)?; + ast::Item::Union(it) => { + process_has_attrs_with_possible_comma( + db, + it.record_field_list()?.fields(), + loc.krate, + &mut remove, + )?; } - }, - ast::Item::Enum(it) => { - process_enum(db, it.variant_list()?, loc.krate, &mut remove)?; + // FIXME: Implement for other items if necessary. As we do not support #[cfg_eval] yet, we do not need to implement it for now + _ => {} } - ast::Item::Union(it) => { - process_has_attrs_with_possible_comma( - db, - it.record_field_list()?.fields(), - loc.krate, - &mut remove, - )?; - } - // FIXME: Implement for other items if necessary. As we do not support #[cfg_eval] yet, we do not need to implement it for now - _ => {} } Some(remove) } diff --git a/crates/test-fixture/src/lib.rs b/crates/test-fixture/src/lib.rs index ca59658359..613f27c795 100644 --- a/crates/test-fixture/src/lib.rs +++ b/crates/test-fixture/src/lib.rs @@ -17,7 +17,7 @@ use hir_expand::{ tt::{Leaf, TokenTree, TopSubtree, TopSubtreeBuilder, TtElement, TtIter}, FileRange, }; -use intern::Symbol; +use intern::{sym, Symbol}; use rustc_hash::FxHashMap; use span::{Edition, EditionedFileId, FileId, Span}; use stdx::itertools::Itertools; @@ -511,6 +511,21 @@ pub fn issue_18898(_attr: TokenStream, input: TokenStream) -> TokenStream { disabled: false, }, ), + ( + r#" +#[proc_macro_attribute] +pub fn disallow_cfg(_attr: TokenStream, input: TokenStream) -> TokenStream { + input +} +"# + .into(), + ProcMacro { + name: Symbol::intern("disallow_cfg"), + kind: ProcMacroKind::Attr, + expander: sync::Arc::new(DisallowCfgProcMacroExpander), + disabled: false, + }, + ), ]) } @@ -865,3 +880,30 @@ impl ProcMacroExpander for Issue18898ProcMacroExpander { }) } } + +// Reads ident type within string quotes, for issue #17479. +#[derive(Debug)] +struct DisallowCfgProcMacroExpander; +impl ProcMacroExpander for DisallowCfgProcMacroExpander { + fn expand( + &self, + subtree: &TopSubtree, + _: Option<&TopSubtree>, + _: &Env, + _: Span, + _: Span, + _: Span, + _: Option, + ) -> Result { + for tt in subtree.token_trees().flat_tokens() { + if let tt::TokenTree::Leaf(tt::Leaf::Ident(ident)) = tt { + if ident.sym == sym::cfg || ident.sym == sym::cfg_attr { + return Err(ProcMacroExpansionError::Panic( + "cfg or cfg_attr found in DisallowCfgProcMacroExpander".to_owned(), + )); + } + } + } + Ok(subtree.clone()) + } +}