gogoast/lib/find.js

The simplest tool to parse/transform/generate code by ast

// 通过简单ast结构查找ast节点

const recast = require('recast');
const visit = recast.types.visit;
const filterProps = require('./filter-prop.js');

const hasOwn = Object.prototype.hasOwnProperty.call.bind(Object.prototype.hasOwnProperty);

function checkIsMatch(full, partial, extraData, strictSequence) {
    return Object.keys(partial).every(prop => {
        if (!full || !partial) {
            // 这个分支存疑，不知道会不会有bug
            return false;
        } else
            if (isObject(partial[prop])) {
                let res = false;
                if (Array.isArray(partial[prop]) && !strictSequence) {
                    if (hasOwn(full, prop)) {
                        res = partial[prop].every(p => {
                            let a = false;
                            full[prop] && full[prop].forEach(f => {
                                if (f && f.type == 'ObjectProperty') {
                                    // 兼容 { a: 1 } 匹配 { 'a': 1 } 这种情况
                                    f.key.name && (f.key.value = f.key.name);
                                    f.key.value && (f.key.name = f.key.value);
                                }
                                if (checkIsMatch(f, p, extraData, strictSequence)) {
                                    a = true;
                                }
                            });
                            return a;
                        });
                    } else {
                        res = false;
                    }
                } else {
                    // todo
                    try {
                        res = hasOwn(full, prop) && checkIsMatch(full[prop], partial[prop], extraData, strictSequence);
                    } catch (e) {
                        console.log(e)
                    }

                }
                return res;
            } else {
                if (partial[prop] == '$_$') {
                    let extra = {
                        structure: full
                    };
                    if (!full) return;
                    switch (full.type) {
                        case 'ThisExpression':
                            extra.value = 'this';
                            break;
                        case 'StringLiteral':
                            extra.value = full.value;
                            break;
                        default:
                            if (full[prop]) {
                                extra.value = full[prop];
                            } else {
                                extra.value = {};
                                filterProps(full, extra.value);
                            }
                    }
                    extraData.push(extra);
                    return true;
                } else if (partial[prop]) {
                    const reg = /^(?:\$\[).*(?=\]\$)/;
                }
                if (full && full.type == 'ObjectProperty') {
                    // 兼容 { a: 1 } 匹配 { 'a': 1 } 这种情况
                    full.key.name && (full.key.value = full.key.name);
                    full.key.value && (full.key.name = full.key.value);
                }
                return full ? full[prop] == partial[prop] : false;
            }
    });
}

function isObject(value) {
    return typeof value === 'object' && value;
}

function find(nodeType, structure, strictSequence = false, deep = 'nn') {
    const nodePathList = [];
    const matchWildCardList = [];
    let isMatch = false;
    const ast = this;
    visit(ast, {
        [`visit${nodeType}`](path) {
            const extraData = [];
            if (deep != 'n' || path.parent.name == 'program') {
                isMatch = checkIsMatch(path.value, structure, extraData, strictSequence);
            } else {
                isMatch = false
            }
            if (isMatch) {
                nodePathList.push(path);
                matchWildCardList.push(extraData);
            }
            switch (deep) {
                case '1':
                    this.abort();
                case 'n':
                    return false;
                case 'nn':
                    this.traverse(path);
                default:
                    return false;
            }
        }
    });
    return { nodePathList, matchWildCardList };
}
module.exports = { find, visit };