From bc46af97423cef7484a806e8282c545d7607889e Mon Sep 17 00:00:00 2001
From: Yacin Tmimi <yacintmimi@gmail.com>
Date: Tue, 19 Oct 2021 01:14:51 -0400
Subject: [PATCH] Retain trailing comments in module when using rustfmt::skip
 attribute

Resolves 5033

Trailing comments at the end of the root Module were removed because the
module span did not extend until the end of the file.

The root Module's span now encompasses the entire file, which ensures
that no comments are lost when using ``#![rustfmt::skip]``
---
 src/modules.rs                             |  6 ++++--
 tests/target/issue-5033/minimum_example.rs |  8 ++++++++
 tests/target/issue-5033/nested_modules.rs  | 11 +++++++++++
 3 files changed, 23 insertions(+), 2 deletions(-)
 create mode 100644 tests/target/issue-5033/minimum_example.rs
 create mode 100644 tests/target/issue-5033/nested_modules.rs

diff --git a/src/modules.rs b/src/modules.rs
index 88d434d759db..9e75f41ae36e 100644
--- a/src/modules.rs
+++ b/src/modules.rs
@@ -16,7 +16,7 @@ use crate::syntux::parser::{
     Directory, DirectoryOwnership, ModError, ModulePathSuccess, Parser, ParserError,
 };
 use crate::syntux::session::ParseSess;
-use crate::utils::contains_skip;
+use crate::utils::{contains_skip, mk_sp};
 
 mod visitor;
 
@@ -135,10 +135,12 @@ impl<'ast, 'sess, 'c> ModResolver<'ast, 'sess> {
             self.visit_mod_from_ast(&krate.items)?;
         }
 
+        let snippet_provider = self.parse_sess.snippet_provider(krate.span);
+
         self.file_map.insert(
             root_filename,
             Module::new(
-                krate.span,
+                mk_sp(snippet_provider.start_pos(), snippet_provider.end_pos()),
                 None,
                 Cow::Borrowed(&krate.items),
                 Cow::Borrowed(&krate.attrs),
diff --git a/tests/target/issue-5033/minimum_example.rs b/tests/target/issue-5033/minimum_example.rs
new file mode 100644
index 000000000000..0e7df41deb2d
--- /dev/null
+++ b/tests/target/issue-5033/minimum_example.rs
@@ -0,0 +1,8 @@
+// leading comment
+
+#![rustfmt::skip]
+fn main() {
+    println!("main"); // commented
+}
+
+// post comment
diff --git a/tests/target/issue-5033/nested_modules.rs b/tests/target/issue-5033/nested_modules.rs
new file mode 100644
index 000000000000..7a11133b60bb
--- /dev/null
+++ b/tests/target/issue-5033/nested_modules.rs
@@ -0,0 +1,11 @@
+#![rustfmt::skip]
+
+mod a {
+    mod b {
+
+    }
+
+    // trailing comment b
+}
+
+// trailing comment a