From 5568c569c03c8c22ce81185b9e49efcaa6866050 Mon Sep 17 00:00:00 2001 From: Georg Semmler Date: Tue, 12 Mar 2024 20:12:03 +0100 Subject: [PATCH] Make `#[diagnostic::on_unimplemented]` format string parsing more robust This commit fixes several issues with the format string parsing of the `#[diagnostic::on_unimplemented]` attribute that were pointed out by @ehuss. In detail it fixes: * Appearing format specifiers (display, etc). For these we generate a warning that the specifier is unsupported. Otherwise we ignore them * Positional arguments. For these we generate a warning that positional arguments are unsupported in that location and replace them with the format string equivalent (so `{}` or `{n}` where n is the index of the positional argument) * Broken format strings with enclosed }. For these we generate a warning about the broken format string and set the emitted message literally to the provided unformatted string * Unknown format specifiers. For these we generate an additional warning about the unknown specifier. Otherwise we emit the literal string as message. This essentially makes those strings behave like `format!` with the minor difference that we do not generate hard errors but only warnings. After that we continue trying to do something unsuprising (mostly either ignoring the broken parts or falling back to just giving back the literal string as provided). Fix #122391 --- compiler/rustc_trait_selection/messages.ftl | 9 + .../error_reporting/on_unimplemented.rs | 189 ++++++++++++----- .../on_unimplemented/broken_format.rs | 45 ++++ .../on_unimplemented/broken_format.stderr | 193 ++++++++++++++++++ 4 files changed, 382 insertions(+), 54 deletions(-) create mode 100644 tests/ui/diagnostic_namespace/on_unimplemented/broken_format.rs create mode 100644 tests/ui/diagnostic_namespace/on_unimplemented/broken_format.stderr diff --git a/compiler/rustc_trait_selection/messages.ftl b/compiler/rustc_trait_selection/messages.ftl index 0dcba0e05f76f..f96bd98523774 100644 --- a/compiler/rustc_trait_selection/messages.ftl +++ b/compiler/rustc_trait_selection/messages.ftl @@ -19,6 +19,9 @@ trait_selection_closure_kind_mismatch = expected a closure that implements the ` trait_selection_closure_kind_requirement = the requirement to implement `{$trait_prefix}{$expected}` derives from here +trait_selection_disallowed_positional_argument = positional format arguments are not allowed here + .help = only named format arguments with the name of one of the generic types are allowed in this context + trait_selection_dump_vtable_entries = vtable entries for `{$trait_ref}`: {$entries} trait_selection_empty_on_clause_in_rustc_on_unimplemented = empty `on`-clause in `#[rustc_on_unimplemented]` @@ -30,6 +33,9 @@ trait_selection_ignored_diagnostic_option = `{$option_name}` is ignored due to p trait_selection_inherent_projection_normalization_overflow = overflow evaluating associated type `{$ty}` +trait_selection_invalid_format_specifier = invalid format specifier + .help = no format specifier are supported in this position + trait_selection_invalid_on_clause_in_rustc_on_unimplemented = invalid `on`-clause in `#[rustc_on_unimplemented]` .label = invalid on-clause here @@ -60,3 +66,6 @@ trait_selection_unable_to_construct_constant_value = unable to construct a const trait_selection_unknown_format_parameter_for_on_unimplemented_attr = there is no parameter `{$argument_name}` on trait `{$trait_name}` .help = expect either a generic argument name or {"`{Self}`"} as format argument + +trait_selection_wrapped_parser_error = {$description} + .label = {$label} diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs index 126bc0c9ec0fc..9e7a53df31994 100644 --- a/compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs +++ b/compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs @@ -367,6 +367,23 @@ pub struct UnknownFormatParameterForOnUnimplementedAttr { trait_name: Symbol, } +#[derive(LintDiagnostic)] +#[diag(trait_selection_disallowed_positional_argument)] +#[help] +pub struct DisallowedPositionalArgument; + +#[derive(LintDiagnostic)] +#[diag(trait_selection_invalid_format_specifier)] +#[help] +pub struct InvalidFormatSpecifier; + +#[derive(LintDiagnostic)] +#[diag(trait_selection_wrapped_parser_error)] +pub struct WrappedParserError { + description: String, + label: String, +} + impl<'tcx> OnUnimplementedDirective { fn parse( tcx: TyCtxt<'tcx>, @@ -758,64 +775,108 @@ impl<'tcx> OnUnimplementedFormatString { let trait_name = tcx.item_name(trait_def_id); let generics = tcx.generics_of(item_def_id); let s = self.symbol.as_str(); - let parser = Parser::new(s, None, None, false, ParseMode::Format); + let mut parser = Parser::new(s, None, None, false, ParseMode::Format); let mut result = Ok(()); - for token in parser { + for token in &mut parser { match token { Piece::String(_) => (), // Normal string, no need to check it - Piece::NextArgument(a) => match a.position { - Position::ArgumentNamed(s) => { - match Symbol::intern(s) { - // `{ThisTraitsName}` is allowed - s if s == trait_name && !self.is_diagnostic_namespace_variant => (), - s if ALLOWED_FORMAT_SYMBOLS.contains(&s) - && !self.is_diagnostic_namespace_variant => - { - () - } - // So is `{A}` if A is a type parameter - s if generics.params.iter().any(|param| param.name == s) => (), - s => { - if self.is_diagnostic_namespace_variant { - tcx.emit_node_span_lint( - UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES, - tcx.local_def_id_to_hir_id(item_def_id.expect_local()), - self.span, - UnknownFormatParameterForOnUnimplementedAttr { - argument_name: s, - trait_name, - }, - ); - } else { - result = Err(struct_span_code_err!( - tcx.dcx(), - self.span, - E0230, - "there is no parameter `{}` on {}", - s, - if trait_def_id == item_def_id { - format!("trait `{trait_name}`") - } else { - "impl".to_string() - } - ) - .emit()); + Piece::NextArgument(a) => { + let format_spec = a.format; + if self.is_diagnostic_namespace_variant + && (format_spec.ty_span.is_some() + || format_spec.width_span.is_some() + || format_spec.precision_span.is_some() + || format_spec.fill_span.is_some()) + { + tcx.emit_node_span_lint( + UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES, + tcx.local_def_id_to_hir_id(item_def_id.expect_local()), + self.span, + InvalidFormatSpecifier, + ); + } + match a.position { + Position::ArgumentNamed(s) => { + match Symbol::intern(s) { + // `{ThisTraitsName}` is allowed + s if s == trait_name && !self.is_diagnostic_namespace_variant => (), + s if ALLOWED_FORMAT_SYMBOLS.contains(&s) + && !self.is_diagnostic_namespace_variant => + { + () + } + // So is `{A}` if A is a type parameter + s if generics.params.iter().any(|param| param.name == s) => (), + s => { + if self.is_diagnostic_namespace_variant { + tcx.emit_node_span_lint( + UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES, + tcx.local_def_id_to_hir_id(item_def_id.expect_local()), + self.span, + UnknownFormatParameterForOnUnimplementedAttr { + argument_name: s, + trait_name, + }, + ); + } else { + result = Err(struct_span_code_err!( + tcx.dcx(), + self.span, + E0230, + "there is no parameter `{}` on {}", + s, + if trait_def_id == item_def_id { + format!("trait `{trait_name}`") + } else { + "impl".to_string() + } + ) + .emit()); + } } } } + // `{:1}` and `{}` are not to be used + Position::ArgumentIs(..) | Position::ArgumentImplicitlyIs(_) => { + if self.is_diagnostic_namespace_variant { + tcx.emit_node_span_lint( + UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES, + tcx.local_def_id_to_hir_id(item_def_id.expect_local()), + self.span, + DisallowedPositionalArgument, + ); + } else { + let reported = struct_span_code_err!( + tcx.dcx(), + self.span, + E0231, + "only named generic parameters are allowed" + ) + .emit(); + result = Err(reported); + } + } } - // `{:1}` and `{}` are not to be used - Position::ArgumentIs(..) | Position::ArgumentImplicitlyIs(_) => { - let reported = struct_span_code_err!( - tcx.dcx(), - self.span, - E0231, - "only named generic parameters are allowed" - ) - .emit(); - result = Err(reported); - } - }, + } + } + } + // we cannot return errors from processing the format string as hard error here + // as the diagnostic namespace gurantees that malformed input cannot cause an error + // + // if we encounter any error while processing we nevertheless want to show it as warning + // so that users are aware that something is not correct + for e in parser.errors { + if self.is_diagnostic_namespace_variant { + tcx.emit_node_span_lint( + UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES, + tcx.local_def_id_to_hir_id(item_def_id.expect_local()), + self.span, + WrappedParserError { description: e.description, label: e.label }, + ); + } else { + let reported = + struct_span_code_err!(tcx.dcx(), self.span, E0231, "{}", e.description,).emit(); + result = Err(reported); } } @@ -853,9 +914,9 @@ impl<'tcx> OnUnimplementedFormatString { let empty_string = String::new(); let s = self.symbol.as_str(); - let parser = Parser::new(s, None, None, false, ParseMode::Format); + let mut parser = Parser::new(s, None, None, false, ParseMode::Format); let item_context = (options.get(&sym::ItemContext)).unwrap_or(&empty_string); - parser + let constructed_message = (&mut parser) .map(|p| match p { Piece::String(s) => s.to_owned(), Piece::NextArgument(a) => match a.position { @@ -895,9 +956,29 @@ impl<'tcx> OnUnimplementedFormatString { } } } + Position::ArgumentImplicitlyIs(_) if self.is_diagnostic_namespace_variant => { + String::from("{}") + } + Position::ArgumentIs(idx) if self.is_diagnostic_namespace_variant => { + format!("{{{idx}}}") + } _ => bug!("broken on_unimplemented {:?} - bad format arg", self.symbol), }, }) - .collect() + .collect(); + // we cannot return errors from processing the format string as hard error here + // as the diagnostic namespace gurantees that malformed input cannot cause an error + // + // if we encounter any error while processing the format string + // we don't want to show the potentially half assembled formated string, + // therefore we fall back to just showing the input string in this case + // + // The actual parser errors are emitted earlier + // as lint warnings in OnUnimplementedFormatString::verify + if self.is_diagnostic_namespace_variant && !parser.errors.is_empty() { + String::from(s) + } else { + constructed_message + } } } diff --git a/tests/ui/diagnostic_namespace/on_unimplemented/broken_format.rs b/tests/ui/diagnostic_namespace/on_unimplemented/broken_format.rs new file mode 100644 index 0000000000000..8d8917fd319cb --- /dev/null +++ b/tests/ui/diagnostic_namespace/on_unimplemented/broken_format.rs @@ -0,0 +1,45 @@ +#[diagnostic::on_unimplemented(message = "{{Test } thing")] +//~^WARN unmatched `}` found +//~|WARN unmatched `}` found +trait ImportantTrait1 {} + +#[diagnostic::on_unimplemented(message = "Test {}")] +//~^WARN positional format arguments are not allowed here +//~|WARN positional format arguments are not allowed here +trait ImportantTrait2 {} + +#[diagnostic::on_unimplemented(message = "Test {1:}")] +//~^WARN positional format arguments are not allowed here +//~|WARN positional format arguments are not allowed here +trait ImportantTrait3 {} + +#[diagnostic::on_unimplemented(message = "Test {Self:123}")] +//~^WARN invalid format specifier +//~|WARN invalid format specifier +trait ImportantTrait4 {} + +#[diagnostic::on_unimplemented(message = "Test {Self:!}")] +//~^WARN expected `'}'`, found `'!'` +//~|WARN expected `'}'`, found `'!'` +//~|WARN unmatched `}` found +//~|WARN unmatched `}` found +trait ImportantTrait5 {} + +fn check_1(_: impl ImportantTrait1) {} +fn check_2(_: impl ImportantTrait2) {} +fn check_3(_: impl ImportantTrait3) {} +fn check_4(_: impl ImportantTrait4) {} +fn check_5(_: impl ImportantTrait5) {} + +fn main() { + check_1(()); + //~^ERROR {{Test } thing + check_2(()); + //~^ERROR Test {} + check_3(()); + //~^ERROR Test {1} + check_4(()); + //~^ERROR Test () + check_5(()); + //~^ERROR Test {Self:!} +} diff --git a/tests/ui/diagnostic_namespace/on_unimplemented/broken_format.stderr b/tests/ui/diagnostic_namespace/on_unimplemented/broken_format.stderr new file mode 100644 index 0000000000000..932e81ca48e49 --- /dev/null +++ b/tests/ui/diagnostic_namespace/on_unimplemented/broken_format.stderr @@ -0,0 +1,193 @@ +warning: unmatched `}` found + --> $DIR/broken_format.rs:1:32 + | +LL | #[diagnostic::on_unimplemented(message = "{{Test } thing")] + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: `#[warn(unknown_or_malformed_diagnostic_attributes)]` on by default + +warning: positional format arguments are not allowed here + --> $DIR/broken_format.rs:6:32 + | +LL | #[diagnostic::on_unimplemented(message = "Test {}")] + | ^^^^^^^^^^^^^^^^^^^ + | + = help: only named format arguments with the name of one of the generic types are allowed in this context + +warning: positional format arguments are not allowed here + --> $DIR/broken_format.rs:11:32 + | +LL | #[diagnostic::on_unimplemented(message = "Test {1:}")] + | ^^^^^^^^^^^^^^^^^^^^^ + | + = help: only named format arguments with the name of one of the generic types are allowed in this context + +warning: invalid format specifier + --> $DIR/broken_format.rs:16:32 + | +LL | #[diagnostic::on_unimplemented(message = "Test {Self:123}")] + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | + = help: no format specifier are supported in this position + +warning: expected `'}'`, found `'!'` + --> $DIR/broken_format.rs:21:32 + | +LL | #[diagnostic::on_unimplemented(message = "Test {Self:!}")] + | ^^^^^^^^^^^^^^^^^^^^^^^^^ + +warning: unmatched `}` found + --> $DIR/broken_format.rs:21:32 + | +LL | #[diagnostic::on_unimplemented(message = "Test {Self:!}")] + | ^^^^^^^^^^^^^^^^^^^^^^^^^ + +warning: unmatched `}` found + --> $DIR/broken_format.rs:1:32 + | +LL | #[diagnostic::on_unimplemented(message = "{{Test } thing")] + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no` + +error[E0277]: {{Test } thing + --> $DIR/broken_format.rs:35:13 + | +LL | check_1(()); + | ------- ^^ the trait `ImportantTrait1` is not implemented for `()` + | | + | required by a bound introduced by this call + | +help: this trait has no implementations, consider adding one + --> $DIR/broken_format.rs:4:1 + | +LL | trait ImportantTrait1 {} + | ^^^^^^^^^^^^^^^^^^^^^ +note: required by a bound in `check_1` + --> $DIR/broken_format.rs:28:20 + | +LL | fn check_1(_: impl ImportantTrait1) {} + | ^^^^^^^^^^^^^^^ required by this bound in `check_1` + +warning: positional format arguments are not allowed here + --> $DIR/broken_format.rs:6:32 + | +LL | #[diagnostic::on_unimplemented(message = "Test {}")] + | ^^^^^^^^^^^^^^^^^^^ + | + = help: only named format arguments with the name of one of the generic types are allowed in this context + = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no` + +error[E0277]: Test {} + --> $DIR/broken_format.rs:37:13 + | +LL | check_2(()); + | ------- ^^ the trait `ImportantTrait2` is not implemented for `()` + | | + | required by a bound introduced by this call + | +help: this trait has no implementations, consider adding one + --> $DIR/broken_format.rs:9:1 + | +LL | trait ImportantTrait2 {} + | ^^^^^^^^^^^^^^^^^^^^^ +note: required by a bound in `check_2` + --> $DIR/broken_format.rs:29:20 + | +LL | fn check_2(_: impl ImportantTrait2) {} + | ^^^^^^^^^^^^^^^ required by this bound in `check_2` + +warning: positional format arguments are not allowed here + --> $DIR/broken_format.rs:11:32 + | +LL | #[diagnostic::on_unimplemented(message = "Test {1:}")] + | ^^^^^^^^^^^^^^^^^^^^^ + | + = help: only named format arguments with the name of one of the generic types are allowed in this context + = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no` + +error[E0277]: Test {1} + --> $DIR/broken_format.rs:39:13 + | +LL | check_3(()); + | ------- ^^ the trait `ImportantTrait3` is not implemented for `()` + | | + | required by a bound introduced by this call + | +help: this trait has no implementations, consider adding one + --> $DIR/broken_format.rs:14:1 + | +LL | trait ImportantTrait3 {} + | ^^^^^^^^^^^^^^^^^^^^^ +note: required by a bound in `check_3` + --> $DIR/broken_format.rs:30:20 + | +LL | fn check_3(_: impl ImportantTrait3) {} + | ^^^^^^^^^^^^^^^ required by this bound in `check_3` + +warning: invalid format specifier + --> $DIR/broken_format.rs:16:32 + | +LL | #[diagnostic::on_unimplemented(message = "Test {Self:123}")] + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | + = help: no format specifier are supported in this position + = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no` + +error[E0277]: Test () + --> $DIR/broken_format.rs:41:13 + | +LL | check_4(()); + | ------- ^^ the trait `ImportantTrait4` is not implemented for `()` + | | + | required by a bound introduced by this call + | +help: this trait has no implementations, consider adding one + --> $DIR/broken_format.rs:19:1 + | +LL | trait ImportantTrait4 {} + | ^^^^^^^^^^^^^^^^^^^^^ +note: required by a bound in `check_4` + --> $DIR/broken_format.rs:31:20 + | +LL | fn check_4(_: impl ImportantTrait4) {} + | ^^^^^^^^^^^^^^^ required by this bound in `check_4` + +warning: expected `'}'`, found `'!'` + --> $DIR/broken_format.rs:21:32 + | +LL | #[diagnostic::on_unimplemented(message = "Test {Self:!}")] + | ^^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no` + +warning: unmatched `}` found + --> $DIR/broken_format.rs:21:32 + | +LL | #[diagnostic::on_unimplemented(message = "Test {Self:!}")] + | ^^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no` + +error[E0277]: Test {Self:!} + --> $DIR/broken_format.rs:43:13 + | +LL | check_5(()); + | ------- ^^ the trait `ImportantTrait5` is not implemented for `()` + | | + | required by a bound introduced by this call + | +help: this trait has no implementations, consider adding one + --> $DIR/broken_format.rs:26:1 + | +LL | trait ImportantTrait5 {} + | ^^^^^^^^^^^^^^^^^^^^^ +note: required by a bound in `check_5` + --> $DIR/broken_format.rs:32:20 + | +LL | fn check_5(_: impl ImportantTrait5) {} + | ^^^^^^^^^^^^^^^ required by this bound in `check_5` + +error: aborting due to 5 previous errors; 12 warnings emitted + +For more information about this error, try `rustc --explain E0277`.