Auto merge of #7773 - Manishearth:update-lints-mods, r=flip1995

Move module declarations back into lib.rs

With #7673 we moved a lot of things from lib.rs to lib.foo.rs. Unfortunately, rustfmt doesn't seem to work when module declarations are included via `include!` (and trying the `mod foo; use foo::*;` trick doesn't seem to work much either in our specific case).

With this PR we continue generating everything in subfiles except for module declarations, which are now generated within lib.rs.

clippy_dev/src/update_lints.rs

@@ -98,6 +98,17 @@ pub fn run(update_mode: UpdateMode) {
     )
     .changed;
 
+    // This has to be in lib.rs, otherwise rustfmt doesn't work
+    file_change |= replace_region_in_file(
+        Path::new("clippy_lints/src/lib.rs"),
+        "begin lints modules",
+        "end lints modules",
+        false,
+        update_mode == UpdateMode::Change,
+        || vec![gen_modules_list(usable_lints.iter())],
+    )
+    .changed;
+
     if file_change && update_mode == UpdateMode::Check {
         exit_with_failure();
     }
@@ -112,11 +123,6 @@ pub fn run(update_mode: UpdateMode) {
         update_mode,
         &gen_deprecated(deprecated_lints.iter()),
     );
-    process_file(
-        "clippy_lints/src/lib.mods.rs",
-        update_mode,
-        &gen_modules_list(usable_lints.iter()),
-    );
 
     let all_group_lints = usable_lints.iter().filter(|l| {
         matches!(