1 use std::collections::BTreeMap;
4 use crate::ast::{self, Ident, Name};
6 use crate::ext::base::{ExtCtxt, MacEager, MacResult};
7 use crate::ext::build::AstBuilder;
8 use crate::parse::token;
10 use crate::symbol::kw;
11 use crate::tokenstream::{TokenTree};
13 use smallvec::smallvec;
16 use crate::diagnostics::metadata::output_metadata;
20 // Maximum width of any line in an extended error description (inclusive).
21 const MAX_DESCRIPTION_WIDTH: usize = 80;
23 /// Error information type.
24 pub struct ErrorInfo {
25 pub description: Option<Name>,
26 pub use_site: Option<Span>
29 /// Mapping from error codes to metadata.
30 pub type ErrorMap = BTreeMap<Name, ErrorInfo>;
32 pub fn expand_diagnostic_used<'cx>(ecx: &'cx mut ExtCtxt<'_>,
34 token_tree: &[TokenTree])
35 -> Box<dyn MacResult+'cx> {
36 let code = match (token_tree.len(), token_tree.get(0)) {
37 (1, Some(&TokenTree::Token(_, token::Ident(code, _)))) => code,
41 ecx.parse_sess.registered_diagnostics.with_lock(|diagnostics| {
42 match diagnostics.get_mut(&code.name) {
43 // Previously used errors.
44 Some(&mut ErrorInfo { description: _, use_site: Some(previous_span) }) => {
45 ecx.struct_span_warn(span, &format!(
46 "diagnostic code {} already used", code
47 )).span_note(previous_span, "previous invocation")
51 Some(ref mut info) => {
52 info.use_site = Some(span);
54 // Unregistered errors.
56 ecx.span_err(span, &format!(
57 "used diagnostic code {} not registered", code
62 MacEager::expr(ecx.expr_tuple(span, Vec::new()))
65 pub fn expand_register_diagnostic<'cx>(ecx: &'cx mut ExtCtxt<'_>,
67 token_tree: &[TokenTree])
68 -> Box<dyn MacResult+'cx> {
69 let (code, description) = match (
75 (1, Some(&TokenTree::Token(_, token::Ident(ref code, _))), None, None) => {
78 (3, Some(&TokenTree::Token(_, token::Ident(ref code, _))),
79 Some(&TokenTree::Token(_, token::Comma)),
80 Some(&TokenTree::Token(_, token::Literal(token::Lit { symbol, .. })))) => {
86 // Check that the description starts and ends with a newline and doesn't
87 // overflow the maximum line width.
88 description.map(|raw_msg| {
89 let msg = raw_msg.as_str();
90 if !msg.starts_with("\n") || !msg.ends_with("\n") {
91 ecx.span_err(span, &format!(
92 "description for error code {} doesn't start and end with a newline",
97 // URLs can be unavoidably longer than the line limit, so we allow them.
98 // Allowed format is: `[name]: https://www.rust-lang.org/`
99 let is_url = |l: &str| l.starts_with("[") && l.contains("]:") && l.contains("http");
101 if msg.lines().any(|line| line.len() > MAX_DESCRIPTION_WIDTH && !is_url(line)) {
102 ecx.span_err(span, &format!(
103 "description for error code {} contains a line longer than {} characters.\n\
104 if you're inserting a long URL use the footnote style to bypass this check.",
105 code, MAX_DESCRIPTION_WIDTH
109 // Add the error to the map.
110 ecx.parse_sess.registered_diagnostics.with_lock(|diagnostics| {
111 let info = ErrorInfo {
115 if diagnostics.insert(code.name, info).is_some() {
116 ecx.span_err(span, &format!(
117 "diagnostic code {} already registered", code
122 let span = span.apply_mark(ecx.current_expansion.mark);
124 let name = Ident::from_str_and_span(&format!("__register_diagnostic_{}", code), span).gensym();
126 MacEager::items(smallvec![
138 pub fn expand_build_diagnostic_array<'cx>(ecx: &'cx mut ExtCtxt<'_>,
140 token_tree: &[TokenTree])
141 -> Box<dyn MacResult+'cx> {
142 assert_eq!(token_tree.len(), 3);
143 let (crate_name, name) = match (&token_tree[0], &token_tree[2]) {
146 &TokenTree::Token(_, token::Ident(ref crate_name, _)),
147 // DIAGNOSTICS ident.
148 &TokenTree::Token(_, token::Ident(ref name, _))
149 ) => (*&crate_name, name),
153 // Output error metadata to `tmp/extended-errors/<target arch>/<crate name>.json`
154 if let Ok(target_triple) = env::var("CFG_COMPILER_HOST_TRIPLE") {
155 ecx.parse_sess.registered_diagnostics.with_lock(|diagnostics| {
156 if let Err(e) = output_metadata(ecx,
158 &crate_name.as_str(),
160 ecx.span_bug(span, &format!(
161 "error writing metadata for triple `{}` and crate `{}`, error: {}, \
163 target_triple, crate_name, e.description(), e.cause()
168 ecx.span_err(span, &format!(
169 "failed to write metadata for crate `{}` because $CFG_COMPILER_HOST_TRIPLE is not set",
173 // Construct the output expression.
175 ecx.parse_sess.registered_diagnostics.with_lock(|diagnostics| {
176 let descriptions: Vec<P<ast::Expr>> =
177 diagnostics.iter().filter_map(|(&code, info)| {
178 info.description.map(|description| {
179 ecx.expr_tuple(span, vec![
180 ecx.expr_str(span, code),
181 ecx.expr_str(span, description)
185 (descriptions.len(), ecx.expr_vec(span, descriptions))
188 let static_ = ecx.lifetime(span, Ident::with_empty_ctxt(kw::StaticLifetime));
189 let ty_str = ecx.ty_rptr(
191 ecx.ty_ident(span, ecx.ident_of("str")),
193 ast::Mutability::Immutable,
201 ast::TyKind::Tup(vec![ty_str.clone(), ty_str])
204 id: ast::DUMMY_NODE_ID,
205 value: ecx.expr_usize(span, count),
210 MacEager::items(smallvec![
214 id: ast::DUMMY_NODE_ID,
215 node: ast::ItemKind::Const(
219 vis: source_map::respan(span.shrink_to_lo(), ast::VisibilityKind::Public),