diff --git a/sample.cc b/sample.cc
deleted file mode 100644
index 1273d87..0000000
--- a/sample.cc
+++ /dev/null
@@ -1,19 +0,0 @@
-int z = 0;
-
-struct __attribute__((annotate("A"))) A {
-  int a;
-  double b;
-  char c[8];
-
-  __attribute__((annotate("foo"))) int foo(int);
-};
-
-template <class T>
-class B {
-  T t;
-  T wibble(T);
-};
-
-double bar(double);
-
-int main() {}
diff --git a/test_py_cppmodel.py b/test_py_cppmodel.py
index 2f3066e..92ee415 100644
--- a/test_py_cppmodel.py
+++ b/test_py_cppmodel.py
@@ -12,12 +12,35 @@
     "-I/Library/Developer/CommandLineTools/usr/include",
 ]
 
+SOURCE = """\
+int z = 0;
+
+struct __attribute__((annotate("A"))) A {
+  int a;
+  double b;
+  char c[8];
+
+  __attribute__((annotate("foo"))) int foo(int);
+};
+
+template <class T>
+class B {
+  T t;
+  T wibble(T);
+};
+
+double bar(double);
+
+int main() {}
+"""
+
 
 class TestCppModel(unittest.TestCase):
     def setUp(self):
         tu = TranslationUnit.from_source(
             "sample.cc",
             COMPILER_ARGS,
+            unsaved_files=[("sample.cc", SOURCE)],
         )
         self.model = py_cppmodel.Model(tu)