Remove box syntax from doctest.rs

Doctests are fairly cold code, so even if there
is a regression, which i doubt, it won't matter.

Author: est31

src/librustdoc/doctest.rs

@@ -103,7 +103,7 @@ pub(crate) fn run(options: RustdocOptions) -> Result<(), ErrorGuaranteed> {
         diagnostic_output: DiagnosticOutput::Default,
         lint_caps,
         parse_sess_created: None,
-        register_lints: Some(box crate::lint::register_lints),
+        register_lints: Some(Box::new(crate::lint::register_lints)),
         override_queries: None,
         make_codegen_backend: None,
         registry: rustc_driver::diagnostics_registry(),
@@ -556,7 +556,7 @@ pub(crate) fn make_test(
             .supports_color();
 
             let emitter = EmitterWriter::new(
-                box io::sink(),
+                Box::new(io::sink()),
                 None,
                 None,
                 fallback_bundle,
@@ -568,7 +568,7 @@ pub(crate) fn make_test(
             );
 
             // FIXME(misdreavus): pass `-Z treat-err-as-bug` to the doctest parser
-            let handler = Handler::with_emitter(false, None, box emitter);
+            let handler = Handler::with_emitter(false, None, Box::new(emitter));
             let sess = ParseSess::with_span_handler(handler, sm);
 
             let mut found_main = false;
@@ -1005,7 +1005,7 @@ impl Tester for Collector {
 
             if let Err(err) = std::fs::create_dir_all(&path) {
                 eprintln!("Couldn't create directory for doctest executables: {}", err);
-                panic::resume_unwind(box ());
+                panic::resume_unwind(Box::new(()));
             }
 
             DirState::Perm(path)
@@ -1034,7 +1034,7 @@ impl Tester for Collector {
                 no_run,
                 test_type: test::TestType::DocTest,
             },
-            testfn: test::DynTestFn(box move || {
+            testfn: test::DynTestFn(Box::new(move || {
                 let report_unused_externs = |uext| {
                     unused_externs.lock().unwrap().push(uext);
                 };
@@ -1105,9 +1105,9 @@ impl Tester for Collector {
                         }
                     }
 
-                    panic::resume_unwind(box ());
+                    panic::resume_unwind(Box::new(()));
                 }
-            }),
+            })),
         });
     }