automatically ignore template files

src/towncrier/_builder.py

@@ -115,6 +115,8 @@ def find_fragments(
     If strict, raise ClickException if any fragments have an invalid name.
     """
     ignored_files = {".gitignore", ".keep", "readme", "readme.md", "readme.rst"}
+    if isinstance(config.template, str):
+        ignored_files.add(config.template)
     if config.ignore:
         ignored_files.update(filename.lower() for filename in config.ignore)
 

src/towncrier/test/test_build.py

@@ -1631,6 +1631,29 @@ def test_invalid_fragment_name(self, runner):
         self.assertEqual(1, result.exit_code, result.output)
         self.assertIn("Invalid news fragment name: feature.124", result.output)
 
+    @with_project(
+        config="""
+        [tool.towncrier]
+        package = "foo"
+        template = ["template.jinja"]
+        """
+    )
+    def test_ignored_template_string(self, runner):
+        """
+        Files used in `template` are automatically ignored.
+        """
+        with open("foo/newsfragments/123.feature", "w") as f:
+            f.write("This has valid filename (control case)")
+        with open("foo/newsfragments/template.jinja", "w") as f:
+            f.write("This template has been automatically ignored")
+        with open("foo/newsfragments/.gitignore", "w") as f:
+            f.write("gitignore is automatically ignored")
+
+        result = runner.invoke(
+            _main, ["--draft", "--date", "01-01-2001", "--version", "1.0.0"]
+        )
+        self.assertEqual(0, result.exit_code, result.output)
+
     @with_project()
     def test_no_ignore_configured(self, runner):
         """