Rollup merge of #146584 - cyrgani:error-codes-macro, r=GuillaumeGomez

remove duplicated columns from `rustc_error_code::error_codes!`

Possible because of rust-lang/rust#146308 ~~, but currently still blocked on the next stage0 bump~~.

compiler/rustc_error_codes/src/error_codes/E0773.md

@@ -1,4 +1,4 @@
-#### this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 This was triggered when multiple macro definitions used the same
 `#[rustc_builtin_macro(..)]`. This is no longer an error.

compiler/rustc_errors/src/codes.rs

@@ -23,15 +23,15 @@ impl fmt::Display for ErrCode {
 rustc_error_messages::into_diag_arg_using_display!(ErrCode);
 
 macro_rules! define_error_code_constants_and_diagnostics_table {
-    ($($name:ident: $num:literal,)*) => (
+    ($($num:literal,)*) => (
         $(
-            pub const $name: $crate::ErrCode = $crate::ErrCode::from_u32($num);
+            pub const ${concat(E, $num)}: $crate::ErrCode = $crate::ErrCode::from_u32($num);
         )*
         pub static DIAGNOSTICS: &[($crate::ErrCode, &str)] = &[
             $( (
-                $name,
+                ${concat(E, $num)},
                 include_str!(
-                    concat!("../../rustc_error_codes/src/error_codes/", stringify!($name), ".md")
+                    concat!("../../rustc_error_codes/src/error_codes/E", stringify!($num), ".md")
                 )
             ), )*
         ];

compiler/rustc_errors/src/lib.rs

@@ -13,6 +13,7 @@
 #![feature(box_patterns)]
 #![feature(default_field_values)]
 #![feature(error_reporter)]
+#![feature(macro_metavar_expr_concat)]
 #![feature(negative_impls)]
 #![feature(never_type)]
 #![feature(rustc_attrs)]

src/tools/tidy/src/error_codes.rs

@@ -91,20 +91,16 @@ fn extract_error_codes(root_path: &Path, check: &mut RunningCheck) -> Vec<String
         let line_index = line_index + 1;
         let line = line.trim();
 
-        if line.starts_with('E') {
-            let split_line = line.split_once(':');
-
-            // Extract the error code from the line. Emit a fatal error if it is not in the correct
-            // format.
-            let Some(split_line) = split_line else {
+        if line.starts_with(|c: char| c.is_ascii_digit()) {
+            let mut chars = line.chars();
+            let err_code = chars.by_ref().take(4).collect::<String>();
+            if chars.next() != Some(',') {
                 check.error(format!(
-                    "{path}:{line_index}: Expected a line with the format `Eabcd: abcd, \
-                    but got \"{line}\" without a `:` delimiter",
+                    "{path}:{line_index}: Expected a line with the format `abcd,` \
+                    but got \"{line}\" without a `,` delimiter",
                 ));
                 continue;
-            };
-
-            let err_code = split_line.0.to_owned();
+            }
 
             // If this is a duplicate of another error code, emit a fatal error.
             if error_codes.contains(&err_code) {
@@ -114,35 +110,13 @@ fn extract_error_codes(root_path: &Path, check: &mut RunningCheck) -> Vec<String
                 continue;
             }
 
-            let mut chars = err_code.chars();
-            assert_eq!(chars.next(), Some('E'));
-            let error_num_as_str = chars.as_str();
-
-            // Ensure that the line references the correct markdown file.
-            let rest = split_line.1.split_once(',');
-            let Some(rest) = rest else {
-                check.error(format!(
-                    "{path}:{line_index}: Expected a line with the format `Eabcd: abcd, \
-                    but got \"{line}\" without a `,` delimiter",
-                ));
-                continue;
-            };
-            if error_num_as_str != rest.0.trim() {
-                check.error(format!(
-                    "{path}:{line_index}: `{}:` should be followed by `{},` but instead found `{}` in \
-                    `compiler/rustc_error_codes/src/lib.rs`",
-                    err_code,
-                    error_num_as_str,
-                    split_line.1,
-                ));
-                continue;
-            }
-            if !rest.1.trim().is_empty() && !rest.1.trim().starts_with("//") {
+            let rest = chars.as_str().trim();
+            if !rest.is_empty() && !rest.starts_with("//") {
                 check.error(format!("{path}:{line_index}: should only have one error per line"));
                 continue;
             }
 
-            error_codes.push(err_code);
+            error_codes.push(format!("E{err_code}"));
         }
     }