Add test to check left priority

test.bats

@@ -15,6 +15,11 @@
 	[ "$result" = "-1" ]
 }
 
+@test "Substraction with left priority" {
+        result="$(echo '8 - 2 - 1 =' | ./eval.out)"
+        [ "$result" = "5" ]
+}
+
 @test "Multiplication priority over addition" {
 	result="$(echo '1+2*3=' | ./eval.out)"
 	[ "$result" = "7" ]
@@ -61,6 +66,11 @@
 	[ "$result" = "5" ]
 }
 
+@test "Division with left priority" {
+        result="$(echo '8 / 4 / 2 =' | ./eval.out)"
+        [ "$result" = "1" ]
+}
+
 @test "Complex division" {
 	result="$(echo '192 / 3 / 16 =' | ./eval.out)"
 	[ "$result" = "4" ]