Support .rs.in as a file extension for Rust files.

When using syntax extensions in stable or beta Rust channels using the syntex
package, it is common to use the file extension .rs.in for the source file, and
.rs for the generated file.

1 files changed, 1 insertions, 1 deletions

diff --git a/pygments/lexers/rust.py b/pygments/lexers/rust.py
index d8939678..5d1162b8 100644
--- a/pygments/lexers/rust.py
+++ b/pygments/lexers/rust.py
@@ -23,7 +23,7 @@ class RustLexer(RegexLexer):
     .. versionadded:: 1.6
     """
     name = 'Rust'
-    filenames = ['*.rs']
+    filenames = ['*.rs', '*.rs.in']
     aliases = ['rust']
     mimetypes = ['text/rust']