Can not express map[string] interface property

[scorpinxia]

I have run some test below TEST1,I want the error happened( variables have no cpu1 struct）,but It just return false

Also I do TEST2 like below , just change field 'cpu1' to 'request1' , It works (it return err , can not fetch cpu from nil )

again I do TEST3 like below , just change '==' to '>' , It works (it return err invalid operation: < float64 (1:27))

any ideas?

1. TEST1

      `{
    	name:      "number expr",
    	matchExpr: "test.hello.request.cpu1 == 0.15",
    	variables: map[string]interface{}{
    		"test": map[string]interface{}{
    			"hello": map[string]interface{}{
    				"request": map[string]interface{}{
    					"cpu": 0.2,
    				},
    			},
    		},
    	},
    },`
   

2. TEST2

      `{
    	name:      "number expr",
    	matchExpr: "test.hello.request1.cpu == 0.15",
    	variables: map[string]interface{}{
    		"test": map[string]interface{}{
    			"hello": map[string]interface{}{
    				"request": map[string]interface{}{
    					"cpu": 0.2,
    				},
    			},
    		},
    	},
    },`
   

3. TEST3

      `{
    	name:      "number expr",
    	matchExpr: "test.hello.request.cpu1 < 0.15",
    	variables: map[string]interface{}{
    		"test": map[string]interface{}{
    			"hello": map[string]interface{}{
    				"request": map[string]interface{}{
    					"cpu": 0.2,
    				},
    			},
    		},
    	},
    },`
   

4. Eval expression code

func MatchExprEval(matchExpr string, variables map[string]interface{}) (bool, error) {
	program, err := expr.Compile(matchExpr, expr.Env(variables), expr.AsBool())
	if err != nil {
		return false, err
	}
	output, err := expr.Run(program, variables)
	if err != nil {
		return false, err
	}

	var outputBool, ok bool
	if outputBool, ok = output.(bool); !ok {
		return false, fmt.Errorf("not a bool result")
	}
	return outputBool, nil
}