Add tests for expr statements

tests/compiler/statements/expr_statement.leo

@@ -0,0 +1,16 @@
+/*
+namespace: Compile
+expectation: Pass
+*/
+
+program test.aleo {
+
+    function foo(a: u8, b: u8) -> () {
+        console.assert_eq(a, b);
+    }
+
+    transition main(a: u8, b: u8) -> u8 {
+        foo(a, b);
+        return a + b;
+    }
+}

tests/compiler/statements/expr_statement_fail.leo

@@ -0,0 +1,26 @@
+/*
+namespace: Compile
+expectation: Fail
+*/
+
+program test.aleo {
+
+    struct Foo {
+        a: u8,
+    }
+
+    transition foo(flag: bool, a: u8, b: u8, foo: Foo, i: i8) -> u8 {
+        a + b;
+        flag ? a : b;
+        foo.a;
+        Foo {
+            a: a,
+        };
+        a;
+        1u8;
+        -i8;
+        ();
+        return a + b;
+    }
+
+}