From f9fa3fe65f561001535b069ed1f55c202758588c Mon Sep 17 00:00:00 2001
From: Arpad Borsos <arpad.borsos@googlemail.com>
Date: Sun, 20 Dec 2020 10:00:32 +0100
Subject: [PATCH] add an attribute to inner doctest fn

---
 src/librustdoc/doctest.rs       | 7 ++++---
 src/librustdoc/doctest/tests.rs | 6 +++---
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/librustdoc/doctest.rs b/src/librustdoc/doctest.rs
index a08ded926402..7313c761eae8 100644
--- a/src/librustdoc/doctest.rs
+++ b/src/librustdoc/doctest.rs
@@ -551,17 +551,18 @@ crate fn make_test(
         } else {
             "_inner".into()
         };
+        let inner_attr = if test_id.is_some() { "#[allow(non_snake_case)] " } else { "" };
         let (main_pre, main_post) = if returns_result {
             (
                 format!(
-                    "fn main() {{ fn {}() -> Result<(), impl core::fmt::Debug> {{\n",
-                    inner_fn_name
+                    "fn main() {{ {}fn {}() -> Result<(), impl core::fmt::Debug> {{\n",
+                    inner_attr, inner_fn_name
                 ),
                 format!("\n}}; {}().unwrap() }}", inner_fn_name),
             )
         } else if test_id.is_some() {
             (
-                format!("fn main() {{ fn {}() {{\n", inner_fn_name),
+                format!("fn main() {{ {}fn {}() {{\n", inner_attr, inner_fn_name),
                 format!("\n}}; {}() }}", inner_fn_name),
             )
         } else {
diff --git a/src/librustdoc/doctest/tests.rs b/src/librustdoc/doctest/tests.rs
index 7c0df673c1b9..1aea85e99708 100644
--- a/src/librustdoc/doctest/tests.rs
+++ b/src/librustdoc/doctest/tests.rs
@@ -304,11 +304,11 @@ fn make_test_named_wrapper() {
     let opts = TestOptions::default();
     let input = "assert_eq!(2+2, 4);";
     let expected = "#![allow(unused)]
-fn main() { fn _doctest_main_some_unique_name() {
+fn main() { #[allow(non_snake_case)] fn _doctest_main__some_unique_name() {
 assert_eq!(2+2, 4);
-}; _doctest_main_some_unique_name() }"
+}; _doctest_main__some_unique_name() }"
         .to_string();
     let (output, len, _) =
-        make_test(input, None, false, &opts, DEFAULT_EDITION, Some("some_unique_name"));
+        make_test(input, None, false, &opts, DEFAULT_EDITION, Some("_some_unique_name"));
     assert_eq!((output, len), (expected, 2));
 }