@pgsz/pg-cli/packages/pg-cli/lib/utils/configTransforms.js

pg-cli脚手架的自我学习

const stringifyJS = require('./stringifyJS')
const merge = require('deepmerge')

const mergeArrayWithDedupe = (a, b) => Array.from(new Set([...a, ...b]))
const mergeOptions = {
    arrayMerge: mergeArrayWithDedupe,
}

const transformJS = {
    read: ({ filename, context }) => {
        try {
            return require(`./${filename}`, context, true)
        } catch (e) {
            return null
        }
    },
    // 第二个参数：过滤的方法函数
    // 4: 文本缩进空格
    write: ({ value }) => `module.exports = ${stringifyJS(value, null, 4)}`,
}

const transformJSON = {
    read: ({ source }) => JSON.parse(source),
    write: ({ value, existing }) => JSON.stringify(merge(existing, value, mergeOptions), null, 4),
}

const transformYAML = {
    read: ({ source }) => require('js-yaml').safeLoad(source),
    write: ({ value, existing }) => require('js-yaml').safeDump(merge(existing, value, mergeOptions), {
        skipInvalid: true,
    }),
}

const transformLines = {
    read: ({ source }) => source.split('\n'),
    write: ({ value, existing }) => {
        if (existing) {
            value = existing.concat(value)
            // Dedupe
            value = value.filter((item, index) => value.indexOf(item) === index)
        }
        return value.join('\n')
    },
}

module.exports = {
    js: transformJS,
    json: transformJSON,
    yaml: transformYAML,
    lines: transformLines,
}