diff options
Diffstat (limited to 'compiler/rustc_macros/src/diagnostics/utils.rs')
| -rw-r--r-- | compiler/rustc_macros/src/diagnostics/utils.rs | 256 |
1 files changed, 255 insertions, 1 deletions
diff --git a/compiler/rustc_macros/src/diagnostics/utils.rs b/compiler/rustc_macros/src/diagnostics/utils.rs index 3efcd216d19..a31bda9ca0d 100644 --- a/compiler/rustc_macros/src/diagnostics/utils.rs +++ b/compiler/rustc_macros/src/diagnostics/utils.rs @@ -1,12 +1,18 @@ -use crate::diagnostics::error::{span_err, throw_span_err, DiagnosticDeriveError}; +use crate::diagnostics::error::{ + span_err, throw_invalid_attr, throw_invalid_nested_attr, throw_span_err, DiagnosticDeriveError, +}; use proc_macro::Span; use proc_macro2::TokenStream; use quote::{format_ident, quote, ToTokens}; use std::collections::{BTreeSet, HashMap}; +use std::fmt; use std::str::FromStr; use syn::{spanned::Spanned, Attribute, Meta, Type, TypeTuple}; +use syn::{MetaList, MetaNameValue, NestedMeta, Path}; use synstructure::{BindingInfo, Structure}; +use super::error::invalid_nested_attr; + /// Checks whether the type name of `ty` matches `name`. /// /// Given some struct at `a::b::c::Foo`, this will return true for `c::Foo`, `b::c::Foo`, or @@ -311,6 +317,7 @@ pub(crate) trait HasFieldMap { /// `Applicability` of a suggestion - mirrors `rustc_errors::Applicability` - and used to represent /// the user's selection of applicability if specified in an attribute. +#[derive(Clone, Copy)] pub(crate) enum Applicability { MachineApplicable, MaybeIncorrect, @@ -367,3 +374,250 @@ pub(crate) fn build_field_mapping<'a>(structure: &Structure<'a>) -> HashMap<Stri fields_map } + +/// Possible styles for suggestion subdiagnostics. +#[derive(Clone, Copy)] +pub(super) enum SuggestionKind { + /// `#[suggestion]` + Normal, + /// `#[suggestion_short]` + Short, + /// `#[suggestion_hidden]` + Hidden, + /// `#[suggestion_verbose]` + Verbose, +} + +impl FromStr for SuggestionKind { + type Err = (); + + fn from_str(s: &str) -> Result<Self, Self::Err> { + match s { + "" => Ok(SuggestionKind::Normal), + "_short" => Ok(SuggestionKind::Short), + "_hidden" => Ok(SuggestionKind::Hidden), + "_verbose" => Ok(SuggestionKind::Verbose), + _ => Err(()), + } + } +} + +impl SuggestionKind { + pub fn to_suggestion_style(&self) -> TokenStream { + match self { + SuggestionKind::Normal => { + quote! { rustc_errors::SuggestionStyle::ShowCode } + } + SuggestionKind::Short => { + quote! { rustc_errors::SuggestionStyle::HideCodeInline } + } + SuggestionKind::Hidden => { + quote! { rustc_errors::SuggestionStyle::HideCodeAlways } + } + SuggestionKind::Verbose => { + quote! { rustc_errors::SuggestionStyle::ShowAlways } + } + } + } +} + +/// Types of subdiagnostics that can be created using attributes +#[derive(Clone)] +pub(super) enum SubdiagnosticKind { + /// `#[label(...)]` + Label, + /// `#[note(...)]` + Note, + /// `#[help(...)]` + Help, + /// `#[warning(...)]` + Warn, + /// `#[suggestion{,_short,_hidden,_verbose}]` + Suggestion { + suggestion_kind: SuggestionKind, + applicability: SpannedOption<Applicability>, + code: TokenStream, + }, + /// `#[multipart_suggestion{,_short,_hidden,_verbose}]` + MultipartSuggestion { + suggestion_kind: SuggestionKind, + applicability: SpannedOption<Applicability>, + }, +} + +impl SubdiagnosticKind { + /// Constructs a `SubdiagnosticKind` from a field or type attribute such as `#[note]`, + /// `#[error(parser::add_paren)]` or `#[suggestion(code = "...")]`. Returns the + /// `SubdiagnosticKind` and the diagnostic slug, if specified. + pub(super) fn from_attr( + attr: &Attribute, + fields: &impl HasFieldMap, + ) -> Result<(SubdiagnosticKind, Option<Path>), DiagnosticDeriveError> { + let span = attr.span().unwrap(); + + let name = attr.path.segments.last().unwrap().ident.to_string(); + let name = name.as_str(); + + let meta = attr.parse_meta()?; + let mut kind = match name { + "label" => SubdiagnosticKind::Label, + "note" => SubdiagnosticKind::Note, + "help" => SubdiagnosticKind::Help, + "warning" => SubdiagnosticKind::Warn, + _ => { + if let Some(suggestion_kind) = + name.strip_prefix("suggestion").and_then(|s| s.parse().ok()) + { + SubdiagnosticKind::Suggestion { + suggestion_kind, + applicability: None, + code: TokenStream::new(), + } + } else if let Some(suggestion_kind) = + name.strip_prefix("multipart_suggestion").and_then(|s| s.parse().ok()) + { + SubdiagnosticKind::MultipartSuggestion { suggestion_kind, applicability: None } + } else { + throw_invalid_attr!(attr, &meta); + } + } + }; + + let nested = match meta { + Meta::List(MetaList { ref nested, .. }) => { + // An attribute with properties, such as `#[suggestion(code = "...")]` or + // `#[error(some::slug)]` + nested + } + Meta::Path(_) => { + // An attribute without a slug or other properties, such as `#[note]` - return + // without further processing. + // + // Only allow this if there are no mandatory properties, such as `code = "..."` in + // `#[suggestion(...)]` + match kind { + SubdiagnosticKind::Label + | SubdiagnosticKind::Note + | SubdiagnosticKind::Help + | SubdiagnosticKind::Warn + | SubdiagnosticKind::MultipartSuggestion { .. } => return Ok((kind, None)), + SubdiagnosticKind::Suggestion { .. } => { + throw_span_err!(span, "suggestion without `code = \"...\"`") + } + } + } + _ => { + throw_invalid_attr!(attr, &meta) + } + }; + + let mut code = None; + + let mut nested_iter = nested.into_iter().peekable(); + + // Peek at the first nested attribute: if it's a slug path, consume it. + let slug = if let Some(NestedMeta::Meta(Meta::Path(path))) = nested_iter.peek() { + let path = path.clone(); + // Advance the iterator. + nested_iter.next(); + Some(path) + } else { + None + }; + + for nested_attr in nested_iter { + let meta = match nested_attr { + NestedMeta::Meta(ref meta) => meta, + NestedMeta::Lit(_) => { + invalid_nested_attr(attr, &nested_attr).emit(); + continue; + } + }; + + let span = meta.span().unwrap(); + let nested_name = meta.path().segments.last().unwrap().ident.to_string(); + let nested_name = nested_name.as_str(); + + let value = match meta { + Meta::NameValue(MetaNameValue { lit: syn::Lit::Str(value), .. }) => value, + Meta::Path(_) => throw_invalid_nested_attr!(attr, &nested_attr, |diag| { + diag.help("a diagnostic slug must be the first argument to the attribute") + }), + _ => { + invalid_nested_attr(attr, &nested_attr).emit(); + continue; + } + }; + + match (nested_name, &mut kind) { + ("code", SubdiagnosticKind::Suggestion { .. }) => { + let formatted_str = fields.build_format(&value.value(), value.span()); + code.set_once(formatted_str, span); + } + ( + "applicability", + SubdiagnosticKind::Suggestion { ref mut applicability, .. } + | SubdiagnosticKind::MultipartSuggestion { ref mut applicability, .. }, + ) => { + let value = Applicability::from_str(&value.value()).unwrap_or_else(|()| { + span_err(span, "invalid applicability").emit(); + Applicability::Unspecified + }); + applicability.set_once(value, span); + } + + // Invalid nested attribute + (_, SubdiagnosticKind::Suggestion { .. }) => { + invalid_nested_attr(attr, &nested_attr) + .help("only `code` and `applicability` are valid nested attributes") + .emit(); + } + (_, SubdiagnosticKind::MultipartSuggestion { .. }) => { + invalid_nested_attr(attr, &nested_attr) + .help("only `applicability` is a valid nested attributes") + .emit() + } + _ => { + invalid_nested_attr(attr, &nested_attr).emit(); + } + } + } + + match kind { + SubdiagnosticKind::Suggestion { code: ref mut code_field, .. } => { + *code_field = if let Some((code, _)) = code { + code + } else { + span_err(span, "suggestion without `code = \"...\"`").emit(); + quote! { "" } + } + } + SubdiagnosticKind::Label + | SubdiagnosticKind::Note + | SubdiagnosticKind::Help + | SubdiagnosticKind::Warn + | SubdiagnosticKind::MultipartSuggestion { .. } => {} + } + + Ok((kind, slug)) + } +} + +impl quote::IdentFragment for SubdiagnosticKind { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + match self { + SubdiagnosticKind::Label => write!(f, "label"), + SubdiagnosticKind::Note => write!(f, "note"), + SubdiagnosticKind::Help => write!(f, "help"), + SubdiagnosticKind::Warn => write!(f, "warn"), + SubdiagnosticKind::Suggestion { .. } => write!(f, "suggestion_with_style"), + SubdiagnosticKind::MultipartSuggestion { .. } => { + write!(f, "multipart_suggestion_with_style") + } + } + } + + fn span(&self) -> Option<proc_macro2::Span> { + None + } +} |