将a[“length”]转变为a.length

目标

var a = 'hello world!';
var b = a['length'];

转化为

var a = 'hello world!';
var b = a.length;

分析

经AST-Tree比较获知差距在于 property 和 computed 这两个路径，替换掉就好了

核心代码

function member2identify(path){
    const init = path.get('init');

    if (!init.isMemberExpression()) return;

    const member_node = init.node;
    const member_property = init.get('property');

    member_node.computed = false;
    let value = member_node.property.value;
    member_property.replaceWith(t.Identifier(value));
}

const vistor = {
    VariableDeclarator:{
        enter: [member2identify]
    }
}

查看结果