Improve 'cannot contain emoji' error.

[rust.git] / compiler / rustc_interface / src / passes.rs

diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs
index b073ee9682fbdfeef72fb6c9ad20f0fca95a9184..da76f221269fe7a61032d0d41b9b43f22d86fa01 100644 (file)
--- a/compiler/rustc_interface/src/passes.rs
+++ b/compiler/rustc_interface/src/passes.rs
@@ -10,7 +10,7 @@
 use rustc_data_structures::parallel;
 use rustc_data_structures::sync::{Lrc, OnceCell, WorkerLocal};
 use rustc_data_structures::temp_dir::MaybeTempDir;
-use rustc_errors::{ErrorReported, PResult};
+use rustc_errors::{Applicability, ErrorReported, PResult};
 use rustc_expand::base::ExtCtxt;
 use rustc_hir::def_id::{StableCrateId, LOCAL_CRATE};
 use rustc_hir::Crate;
@@ -35,7 +35,7 @@
 use rustc_session::search_paths::PathKind;
 use rustc_session::{Limit, Session};
 use rustc_span::symbol::{sym, Ident, Symbol};
-use rustc_span::FileName;
+use rustc_span::{FileName, MultiSpan};
 use rustc_trait_selection::traits;
 use rustc_typeck as typeck;
 use tempfile::Builder as TempFileBuilder;
@@ -323,7 +323,7 @@ pub fn configure_and_expand(
 
         let crate_attrs = krate.attrs.clone();
         let extern_mod_loaded = |ident: Ident, attrs, items, span| {
-            let krate = ast::Crate { attrs, items, span };
+            let krate = ast::Crate { attrs, items, span, is_placeholder: None };
             pre_expansion_lint(sess, lint_store, &krate, &crate_attrs, &ident.name.as_str());
             (krate.attrs, krate.items)
         };
@@ -450,6 +450,35 @@ pub fn configure_and_expand(
         });
     }
 
+    // Gate identifiers containing invalid Unicode codepoints that were recovered during lexing.
+    sess.parse_sess.bad_unicode_identifiers.with_lock(|identifiers| {
+        let mut identifiers: Vec<_> = identifiers.drain().collect();
+        identifiers.sort_by_key(|&(key, _)| key);
+        for (ident, mut spans) in identifiers.into_iter() {
+            spans.sort();
+            if ident == sym::ferris {
+                let first_span = spans[0];
+                sess.diagnostic()
+                    .struct_span_err(
+                        MultiSpan::from(spans),
+                        "Ferris cannot be used as an identifier",
+                    )
+                    .span_suggestion(
+                        first_span,
+                        "try using their name instead",
+                        "ferris".to_string(),
+                        Applicability::MaybeIncorrect,
+                    )
+                    .emit();
+            } else {
+                sess.diagnostic().span_err(
+                    MultiSpan::from(spans),
+                    &format!("identifiers cannot contain emoji: `{}`", ident),
+                );
+            }
+        }
+    });
+
     Ok(krate)
 }