Add a pi test (currently broken)
diff --git a/tests/all.txt b/tests/all.txt
index 1b75f6f..ee07088 100644
--- a/tests/all.txt
+++ b/tests/all.txt
@@ -9,4 +9,5 @@
 basic
 parse
 print
+pi
 arctangent
diff --git a/tests/pi.txt b/tests/pi.txt
new file mode 100644
index 0000000..b98419f
--- /dev/null
+++ b/tests/pi.txt
@@ -0,0 +1,4 @@
+for (i = 0; i <= 100; ++i) {
+	scale = i
+	4 * a(1)
+}