diff --git a/pre_commit_hooks/requirements_txt_fixer.py b/pre_commit_hooks/requirements_txt_fixer.py
index 8e97bcf..04590e4 100644
--- a/pre_commit_hooks/requirements_txt_fixer.py
+++ b/pre_commit_hooks/requirements_txt_fixer.py
@@ -60,7 +60,10 @@ class Requirement:
         )
 
     def contains_version_specifier(self) -> bool:
-        return bool(self.VERSION_SPECIFIED.match(self.value))
+        return (
+            self.value is not None and
+            bool(self.VERSION_SPECIFIED.match(self.value))
+        )
 
     def append_value(self, value: bytes) -> None:
         if self.value is not None:
@@ -171,7 +174,9 @@ def main(argv: Sequence[str] | None = None) -> int:
 
     for arg in args.filenames:
         with open(arg, 'rb+') as file_obj:
-            ret_for_file = fix_requirements(file_obj, args.fail_without_version)
+            ret_for_file = fix_requirements(
+                file_obj, args.fail_without_version,
+            )
 
             if ret_for_file:
                 print(f'Error in file {arg}')
diff --git a/tests/requirements_txt_fixer_test.py b/tests/requirements_txt_fixer_test.py
index b12f2f3..b35585c 100644
--- a/tests/requirements_txt_fixer_test.py
+++ b/tests/requirements_txt_fixer_test.py
@@ -120,9 +120,24 @@ from pre_commit_hooks.requirements_txt_fixer import Requirement
             b'a=2.0.0 \\\n --hash=sha256:abcd\nb==1.0.0\n',
         ),
         (b'bar\nfoo\n', ['--fail-without-version'], FAIL, b'bar\nfoo\n'),
-        (b'bar==1.0\nfoo==1.1a\n', ['--fail-without-version'], PASS, b'bar==1.0\nfoo==1.1a\n'),
-        (b'#test\nbar==1.0\nfoo==1.1a\n', ['--fail-without-version'], PASS, b'#test\nbar==1.0\nfoo==1.1a\n'),
-        (b'bar==1.0\n#test\nfoo==1.1a\n', ['--fail-without-version'], PASS, b'bar==1.0\n#test\nfoo==1.1a\n'),
+        (
+            b'bar==1.0\nfoo==1.1a\n',
+            ['--fail-without-version'],
+            PASS,
+            b'bar==1.0\nfoo==1.1a\n',
+        ),
+        (
+            b'#test\nbar==1.0\nfoo==1.1a\n',
+            ['--fail-without-version'],
+            PASS,
+            b'#test\nbar==1.0\nfoo==1.1a\n',
+        ),
+        (
+            b'bar==1.0\n#test\nfoo==1.1a\n',
+            ['--fail-without-version'],
+            PASS,
+            b'bar==1.0\n#test\nfoo==1.1a\n',
+        ),
     ),
 )
 def test_integration(input_s, argv, expected_retval, output, tmpdir):