@atomist/sdm-pack-changelog/lib/changelog/changelogParser.js

Extension Pack for an Atomist SDM to manage changelogs

// Copied from https://github.com/hypermodules/changelog-parser
// Changed so that it doesn't remove markdown formatting in list items

var EOL = require('os').EOL
var lineReader = require('line-reader')

// patterns
var semver = /\[?v?([\w\d.-]+\.[\w\d.-]+[a-zA-Z0-9])\]?/
var date = /.*[ ](\d\d?\d?\d?[-/.]\d\d?[-/.]\d\d?\d?\d?).*/
var subhead = /^###/
var listitem = /^[*-]/

function parseChangelog (file, callback) {
    // return a Promise if invoked without a `callback`
    if (!callback || typeof callback !== 'function') {
        return doParse(file)
    }

    // otherwise, parse log and invoke callback
    doParse(file).then(function (log) {
        callback(null, log)
    })
}

function doParse (file) {
    var data = {
        log: { versions: [] },
        current: null
    }

    // allow `handleLine` to mutate log/current data as `this`.
    var cb = handleLine.bind(data)

    return new Promise(function (resolve, reject) {
        lineReader.eachLine(file, cb, EOL).then(function () {
            // push last version into log
            pushCurrent(data)

            // clean up description
            data.log.description = clean(data.log.description)
            if (data.log.description === '') delete data.log.description

            resolve(data.log)
        })
    })
}

function handleLine (line) {
    // skip line if it's a link label
    if (line.match(/^\[[^[\]]*\] *?:/)) return

    // set title if it's there
    if (!this.log.title && line.match(/^# ?[^#]/)) {
        this.log.title = line.substring(1).trim()
        return
    }

    // new version found!
    if (line.match(/^## ?[^#]/)) {
        if (this.current && this.current.title) pushCurrent(this)

        this.current = versionFactory()

        if (semver.exec(line)) this.current.version = semver.exec(line)[1]

        this.current.title = line.substring(2).trim()

        if (this.current.title && date.exec(this.current.title)) this.current.date = date.exec(this.current.title)[1]

        return
    }

    // deal with body or description content
    if (this.current) {
        this.current.body += line + EOL

        // handle case where current line is a 'subhead':
        // - 'handleize' subhead.
        // - add subhead to 'parsed' data if not already present.
        if (subhead.exec(line)) {
            var key = line.replace('###', '').trim()

            if (!this.current.parsed[key]) {
                this.current.parsed[key] = []
                this.current._private.activeSubhead = key
            }
        }

        // handle case where current line is a 'list item':
        if (listitem.exec(line)) {
            // add line to 'catch all' array
            this.current.parsed._.push(line)

            // add line to 'active subhead' if applicable (eg. 'Added', 'Changed', etc.)
            if (this.current._private.activeSubhead) {
                this.current.parsed[this.current._private.activeSubhead].push(line)
            }
        }
    } else {
        this.log.description = (this.log.description || '') + line + EOL
    }
}

function versionFactory () {
    return {
        version: null,
        title: null,
        date: null,
        body: '',
        parsed: {
            _: []
        },
        _private: {
            activeSubhead: null
        }
    }
}

function pushCurrent (data) {
    // remove private properties
    delete data.current._private

    data.current.body = clean(data.current.body)
    data.log.versions.push(data.current)
}

function clean (str) {
    if (!str) return ''

    // trim
    str = str.trim()
    // remove leading newlines
    str = str.replace(new RegExp('[' + EOL + ']*'), '')
    // remove trailing newlines
    str = str.replace(new RegExp('[' + EOL + ']*$'), '')

    return str
}

module.exports = parseChangelog