diff options
Diffstat (limited to 'compiler/rustc_macros/src/diagnostics/utils.rs')
| -rw-r--r-- | compiler/rustc_macros/src/diagnostics/utils.rs | 105 |
1 files changed, 94 insertions, 11 deletions
diff --git a/compiler/rustc_macros/src/diagnostics/utils.rs b/compiler/rustc_macros/src/diagnostics/utils.rs index 61d5007fc30..374c795d0a6 100644 --- a/compiler/rustc_macros/src/diagnostics/utils.rs +++ b/compiler/rustc_macros/src/diagnostics/utils.rs @@ -2,7 +2,7 @@ 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 proc_macro2::{Ident, TokenStream}; use quote::{format_ident, quote, ToTokens}; use std::cell::RefCell; use std::collections::{BTreeSet, HashMap}; @@ -395,6 +395,82 @@ pub(super) fn build_field_mapping<'v>(variant: &VariantInfo<'v>) -> HashMap<Stri fields_map } +#[derive(Copy, Clone, Debug)] +pub(super) enum AllowMultipleAlternatives { + No, + Yes, +} + +/// Constructs the `format!()` invocation(s) necessary for a `#[suggestion*(code = "foo")]` or +/// `#[suggestion*(code("foo", "bar"))]` attribute field +pub(super) fn build_suggestion_code( + code_field: &Ident, + meta: &Meta, + fields: &impl HasFieldMap, + allow_multiple: AllowMultipleAlternatives, +) -> TokenStream { + let values = match meta { + // `code = "foo"` + Meta::NameValue(MetaNameValue { lit: syn::Lit::Str(s), .. }) => vec![s], + // `code("foo", "bar")` + Meta::List(MetaList { nested, .. }) => { + if let AllowMultipleAlternatives::No = allow_multiple { + span_err( + meta.span().unwrap(), + "expected exactly one string literal for `code = ...`", + ) + .emit(); + vec![] + } else if nested.is_empty() { + span_err( + meta.span().unwrap(), + "expected at least one string literal for `code(...)`", + ) + .emit(); + vec![] + } else { + nested + .into_iter() + .filter_map(|item| { + if let NestedMeta::Lit(syn::Lit::Str(s)) = item { + Some(s) + } else { + span_err( + item.span().unwrap(), + "`code(...)` must contain only string literals", + ) + .emit(); + None + } + }) + .collect() + } + } + _ => { + span_err( + meta.span().unwrap(), + r#"`code = "..."`/`code(...)` must contain only string literals"#, + ) + .emit(); + vec![] + } + }; + + if let AllowMultipleAlternatives::Yes = allow_multiple { + let formatted_strings: Vec<_> = values + .into_iter() + .map(|value| fields.build_format(&value.value(), value.span())) + .collect(); + quote! { let #code_field = [#(#formatted_strings),*].into_iter(); } + } else if let [value] = values.as_slice() { + let formatted_str = fields.build_format(&value.value(), value.span()); + quote! { let #code_field = #formatted_str; } + } else { + // error handled previously + quote! { let #code_field = String::new(); } + } +} + /// Possible styles for suggestion subdiagnostics. #[derive(Clone, Copy)] pub(super) enum SuggestionKind { @@ -571,21 +647,23 @@ impl SubdiagnosticKind { 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, + let string_value = match meta { + Meta::NameValue(MetaNameValue { lit: syn::Lit::Str(value), .. }) => Some(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; - } + _ => None, }; match (nested_name, &mut kind) { ("code", SubdiagnosticKind::Suggestion { code_field, .. }) => { - let formatted_str = fields.build_format(&value.value(), value.span()); - let code_init = quote! { let #code_field = #formatted_str; }; + let code_init = build_suggestion_code( + code_field, + meta, + fields, + AllowMultipleAlternatives::Yes, + ); code.set_once(code_init, span); } ( @@ -593,6 +671,11 @@ impl SubdiagnosticKind { SubdiagnosticKind::Suggestion { ref mut applicability, .. } | SubdiagnosticKind::MultipartSuggestion { ref mut applicability, .. }, ) => { + let Some(value) = string_value else { + invalid_nested_attr(attr, &nested_attr).emit(); + continue; + }; + let value = Applicability::from_str(&value.value()).unwrap_or_else(|()| { span_err(span, "invalid applicability").emit(); Applicability::Unspecified @@ -623,7 +706,7 @@ impl SubdiagnosticKind { init } else { span_err(span, "suggestion without `code = \"...\"`").emit(); - quote! { let #code_field: String = unreachable!(); } + quote! { let #code_field = std::iter::empty(); } }; } SubdiagnosticKind::Label @@ -644,7 +727,7 @@ impl quote::IdentFragment for SubdiagnosticKind { SubdiagnosticKind::Note => write!(f, "note"), SubdiagnosticKind::Help => write!(f, "help"), SubdiagnosticKind::Warn => write!(f, "warn"), - SubdiagnosticKind::Suggestion { .. } => write!(f, "suggestion_with_style"), + SubdiagnosticKind::Suggestion { .. } => write!(f, "suggestions_with_style"), SubdiagnosticKind::MultipartSuggestion { .. } => { write!(f, "multipart_suggestion_with_style") } |