Auto merge of #69260 - GuillaumeGomez:create-E0747-error-code, r=varkor,estebank

Create E0747 error code for unterminated raw strings Reopening of #66035. r? @estebank

Author: bors

src/librustc_error_codes/error_codes.rs

@@ -418,6 +418,7 @@ E0744: include_str!("./error_codes/E0744.md"),
 E0745: include_str!("./error_codes/E0745.md"),
 E0746: include_str!("./error_codes/E0746.md"),
 E0747: include_str!("./error_codes/E0747.md"),
+E0748: include_str!("./error_codes/E0748.md"),
 ;
 // E0006, // merged with E0005
 // E0008, // cannot bind by-move into a pattern guard

src/librustc_error_codes/error_codes/E0748.md

@@ -0,0 +1,16 @@
+A raw string isn't correctly terminated because the trailing `#` count doesn't
+match its leading `#` count.
+
+Erroneous code example:
+
+```compile_fail,E0748
+let dolphins = r##"Dolphins!"#; // error!
+```
+
+To terminate a raw string, you have to have the same number of `#` at the end
+as at the beginning. Example:
+
+```
+let dolphins = r#"Dolphins!"#; // One `#` at the beginning, one at the end so
+ // all good!
+```

src/librustc_parse/lexer/mod.rs

@@ -1,5 +1,5 @@
 use rustc_data_structures::sync::Lrc;
-use rustc_errors::{DiagnosticBuilder, FatalError};
+use rustc_errors::{error_code, DiagnosticBuilder, FatalError};
 use rustc_lexer::unescape;
 use rustc_lexer::Base;
 use rustc_session::parse::ParseSess;
@@ -495,7 +495,11 @@ impl<'a> StringReader<'a> {
  }
 
  fn report_unterminated_raw_string(&self, start: BytePos, n_hashes: usize) -> ! {
- let mut err = self.struct_span_fatal(start, start, "unterminated raw string");
+ let mut err = self.sess.span_diagnostic.struct_span_fatal_with_code(
+ self.mk_sp(start, start),
+ "unterminated raw string",
+ error_code!(E0748),
+ );
  err.span_label(self.mk_sp(start, start), "unterminated raw string");
 
  if n_hashes > 0 {

src/test/ui/parser/raw-byte-string-eof.stderr

@@ -1,4 +1,4 @@
-error: unterminated raw string
+error[E0748]: unterminated raw string
  --> $DIR/raw-byte-string-eof.rs:2:5
  |
 LL | br##"a"#;
@@ -8,3 +8,4 @@ LL | br##"a"#;
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0748`.

src/test/ui/parser/raw-str-unterminated.stderr

@@ -1,4 +1,4 @@
-error: unterminated raw string
+error[E0748]: unterminated raw string
  --> $DIR/raw-str-unterminated.rs:2:5
  |
 LL | r#" string literal goes on
@@ -8,3 +8,4 @@ LL | r#" string literal goes on
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0748`.

src/test/ui/parser/raw/raw_string.stderr

@@ -1,4 +1,4 @@
-error: unterminated raw string
+error[E0748]: unterminated raw string
  --> $DIR/raw_string.rs:2:13
  |
 LL | let x = r##"lol"#;
@@ -8,3 +8,4 @@ LL | let x = r##"lol"#;
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0748`.