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Commit 459b67a

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Rollup merge of #146090 - Kobzol:invisible-origin-eq, r=petrochenkov
Derive `PartialEq` for `InvisibleOrigin` For #145354, we need `PartialEq` for `TokenStream` to "just work". However, due to the special comparison implementation that was used for `InvisibleOrigin`, this wasn't the case. So I derived `PartialEq` for `InvisibleOrigin`, and used the previous special comparison logic only on the single place where it was actually required. r? ``@petrochenkov``
2 parents 4fec477 + a8537ab commit 459b67a

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-19
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2 files changed

+21
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‎compiler/rustc_ast/src/token.rs‎

Lines changed: 3 additions & 17 deletions
Original file line numberDiff line numberDiff line change
@@ -22,8 +22,7 @@ pub enum CommentKind {
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Block,
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}
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// This type must not implement `Hash` due to the unusual `PartialEq` impl below.
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#[derive(Copy, Clone, Debug, Encodable, Decodable, HashStable_Generic)]
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#[derive(Copy, Clone, PartialEq, Debug, Encodable, Decodable, HashStable_Generic)]
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pub enum InvisibleOrigin {
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// From the expansion of a metavariable in a declarative macro.
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MetaVar(MetaVarKind),
@@ -45,20 +44,6 @@ impl InvisibleOrigin {
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}
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}
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48-
impl PartialEq for InvisibleOrigin {
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#[inline]
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fn eq(&self, _other: &InvisibleOrigin) -> bool {
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// When we had AST-based nonterminals we couldn't compare them, and the
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// old `Nonterminal` type had an `eq` that always returned false,
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// resulting in this restriction:
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// https://doc.rust-lang.org/nightly/reference/macros-by-example.html#forwarding-a-matched-fragment
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// This `eq` emulates that behaviour. We could consider lifting this
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// restriction now but there are still cases involving invisible
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// delimiters that make it harder than it first appears.
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false
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}
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}
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/// Annoyingly similar to `NonterminalKind`, but the slight differences are important.
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#[derive(Debug, Copy, Clone, PartialEq, Eq, Encodable, Decodable, Hash, HashStable_Generic)]
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pub enum MetaVarKind {
@@ -142,7 +127,8 @@ impl Delimiter {
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}
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}
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145-
// This exists because `InvisibleOrigin`s should be compared. It is only used for assertions.
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// This exists because `InvisibleOrigin`s should not be compared. It is only used for
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// assertions.
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pub fn eq_ignoring_invisible_origin(&self, other: &Delimiter) -> bool {
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match (self, other) {
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(Delimiter::Parenthesis, Delimiter::Parenthesis) => true,

‎compiler/rustc_expand/src/mbe/macro_parser.rs‎

Lines changed: 18 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -77,7 +77,7 @@ use std::rc::Rc;
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pub(crate) use NamedMatch::*;
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pub(crate) use ParseResult::*;
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use rustc_ast::token::{self, DocComment, NonterminalKind, Token};
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use rustc_ast::token::{self, DocComment, NonterminalKind, Token,TokenKind};
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use rustc_data_structures::fx::FxHashMap;
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use rustc_errors::ErrorGuaranteed;
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use rustc_lint_defs::pluralize;
@@ -397,7 +397,23 @@ fn token_name_eq(t1: &Token, t2: &Token) -> bool {
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{
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ident1.name == ident2.name && is_raw1 == is_raw2
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} else {
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t1.kind == t2.kind
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// Note: we SHOULD NOT use `t1.kind == t2.kind` here, and we should instead compare the
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// tokens using the special comparison logic below.
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// It makes sure that variants containing `InvisibleOrigin` will
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// never compare equal to one another.
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//
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// When we had AST-based nonterminals we couldn't compare them, and the
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// old `Nonterminal` type had an `eq` that always returned false,
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// resulting in this restriction:
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// <https://doc.rust-lang.org/nightly/reference/macros-by-example.html#forwarding-a-matched-fragment>
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// This comparison logic emulates that behaviour. We could consider lifting this
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// restriction now but there are still cases involving invisible
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// delimiters that make it harder than it first appears.
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match (t1.kind, t2.kind) {
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(TokenKind::OpenInvisible(_) | TokenKind::CloseInvisible(_), _)
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| (_, TokenKind::OpenInvisible(_) | TokenKind::CloseInvisible(_)) => false,
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(a, b) => a == b,
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}
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}
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}
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