Convert test-cvar.rkt tests to rackunit, test for subtraction

test-cvar.rkt

@@ -1,5 +1,8 @@
 #lang racket
 
+(provide cvar-tests)
+
+(require rackunit)
 (require "test-util.rkt")
 (require "cvar.rkt")
 
@@ -7,33 +10,42 @@
     (Return (Int 0)))
 
 (define seq-2
-    (Seq (Assign (Var 'x) (Int 42))
-     (Return (Int 42))))
+    (Seq (Assign (Var 'x) (Int 3))
+     (Return (Prim '- (list (Int 1) (Var 'x))))))
 
 (define seq-3
     (Seq (Assign (Var 'x) (Int 42))
-     (Return (Prim '+ (list (Int 1) (Var 'x))))))
+     (Return (Int 42))))
 
 (define seq-4
+    (Seq (Assign (Var 'x) (Int 42))
+     (Return (Prim '+ (list (Int 1) (Var 'x))))))
+
+(define seq-5
     (Return (Prim 'read '())))
 
 (define (make-start-seq seq)
     (CProgram '() `((start . ,seq))))
 
-(test-eq
+(define cvar-tests
+ (test-suite
+  "CVar tests"
+  (test-case
+   "CVar interpretation tests"
+   (check-equal?
       (interp-CVar (make-start-seq seq-1))
       0)
-
-(test-eq
+   (check-equal?
       (interp-CVar (make-start-seq seq-2))
-   42)
-
-(test-eq
+      -2)
+   (check-equal?
       (interp-CVar (make-start-seq seq-3))
-   43)
-
-(with-input-from-num-list '(21)
- (lambda ()
-  (test-eq
+      42)
+   (check-equal?
       (interp-CVar (make-start-seq seq-4))
-     21)))
+      43)
+   (with-input-from-num-list '(21)
+    (lambda ()
+     (check-equal?
+        (interp-CVar (make-start-seq seq-5))
+        21))))))