diff --git a/testdata/parser/negative/17.txt b/testdata/parser/negative/17.txt
new file mode 100644
index 0000000000000000000000000000000000000000..a900a293c64892c8ad668d72471ad85d1a6a420d
--- /dev/null
+++ b/testdata/parser/negative/17.txt
@@ -0,0 +1,3 @@
+Parse error at 17.pdl:7:4: Unassignable expression
+	x + y = 0;
+	  ^