Init

tests/forth/control_flow.rs

@@ -0,0 +1,64 @@
+use super::harness::*;
+
+#[test]
+fn if_then_true() {
+    expect_int("1 if 42 then", 42);
+}
+
+#[test]
+fn if_then_false() {
+    let f = run("0 if 42 then");
+    assert!(f.stack().is_empty());
+}
+
+#[test]
+fn if_then_with_base() {
+    expect_int("100 0 if 50 + then", 100);
+}
+
+#[test]
+fn if_else_true() {
+    expect_int("1 if 42 else 99 then", 42);
+}
+
+#[test]
+fn if_else_false() {
+    expect_int("0 if 42 else 99 then", 99);
+}
+
+#[test]
+fn nested_tt() {
+    expect_int("1 if 1 if 100 else 200 then else 300 then", 100);
+}
+
+#[test]
+fn nested_tf() {
+    expect_int("1 if 0 if 100 else 200 then else 300 then", 200);
+}
+
+#[test]
+fn nested_f() {
+    expect_int("0 if 1 if 100 else 200 then else 300 then", 300);
+}
+
+#[test]
+fn if_with_computation() {
+    expect_int("3 2 gt if 42 else 99 then", 42);
+}
+
+#[test]
+fn missing_then() {
+    expect_error("1 if 42", "missing 'then'");
+}
+
+#[test]
+fn deeply_nested() {
+    expect_int("1 if 1 if 1 if 42 then then then", 42);
+}
+
+#[test]
+fn chained_conditionals() {
+    // First if leaves nothing, second if runs
+    let f = run("0 if 1 then 1 if 42 then");
+    assert_eq!(stack_int(&f), 42);
+}