How to use the through2-filter.obj function in through2-filter

_colourfn(wrap(expected, 34)) + '\n'
    }
    callback(null, output)
  }

  function flush (_callback) {
    outputStream.push('\n' + chalk.yellow(repeat('\u2500', 80)) + '\n\n')
    this.emit(equal ? 'pass' : 'fail', this.__(equal ? 'compare.pass' : 'compare.fail'))
    _callback(null)
    callback(null, equal) // process() callback
  }

  outputStream = through2.obj(transform.bind(this), flush.bind(this))

  tuple(this.submissionStdout.pipe(split()).pipe(filter.obj(checkSenecaLogs)),
        this.solutionStdout.pipe(split()).pipe(filter.obj(checkSenecaLogs)))
    .pipe(outputStream)
    .pipe(process.stdout)
}

function parseUploadPack(opts) {
    var filter = throughFilter.obj(function(line) {
        return line.type == parsePktLineMeta.TYPES.PACKFILE;
    });

    return combine.obj(
        // Parse as lines
        parsePktLines(),

        // Parse metatdata of lines
        parsePktLineMeta(),

        // Filter packs
        filter,

        // Parse pack as objects
        parsePack(opts),

return combine.obj(
        // Parse as lines
        parsePktLines(),

        // Parse metatdata of lines
        parsePktLineMeta(),

        // Filter packs
        filter,

        // Parse pack as objects
        parsePack(opts),

        // Not sure why... But without this filter, .on('data') doesn't work
        throughFilter.obj(function() {
            return true;
        })
    );
}

var tcAnalysis = function(period) {
              return helpers.codeMaat.temporalCouplingAnalysis(helpers.files.vcsNormalisedLog(period))
              .pipe(filter.obj(_.partial(utils.pathMatchers.isCoupledWith, context.parameters.targetFile)));
            };

module.exports.create = function create() {
  return filter.obj(_.negate(isNullIslandPostalCode));
};

run: function(publisher) {
            publisher.enableDiagram('sum-of-coupling');
            var stream = helpers.codeMaat.sumCouplingAnalysis(helpers.files.vcsNormalisedLog(context.dateRange))
              .pipe(filter.obj(function(obj) { return context.repository.fileExists(obj.path); }));
            return utils.json.objectArrayToFileStream(publisher.addReportFile(), stream);
          }
        }, vcsFunctions.vcsLogDump);

js: bundle =>
                merge(
                    gulp.src(pathToYm),
                    bundle.src('js').pipe(filter(f => ~['vanilla.js', 'browser.js', 'js'].indexOf(f.tech))),
                    bundle.src('js').pipe(filter(file => file.tech === 'bemhtml.js'))
                        .pipe(concat('browser.bemhtml.js')).pipe(bemhtml({ elemJsInstances: true, exportName: 'BEMHTML' }))
                )
                    .pipe(concat(bundle.name + '.min.js'))
                    .pipe(gulpif(isProd, uglify())),
            tmpls: bundle =>

module.exports.create = function create() {
  return filter.obj((record) => {
    return !isNullIsland(record) && !isPostalCodeOnNullIsland(record);
  });
};

var temporalCouplingAnalysis = pp.streamProcessor().read(function() {
                  return helpers.codeMaat
                    .temporalCouplingAnalysis(helpers.files.vcsNormalisedLog(context.dateRange), { '-t': 1 })
                    .pipe(filter.obj(function(obj) {
                      return context.repository.fileExists(obj.path) && context.repository.fileExists(obj.coupledPath);
                    }));
                });

js: bundle =>
                merge(
                    gulp.src(require.resolve('ym')),
                    bundle.src('js').pipe(filter(f => ~['vanilla.js', 'browser.js', 'js'].indexOf(f.tech))),
                    bundle.src('js').pipe(filter(file => file.tech === 'bemhtml.js'))
                        .pipe(concat('browser.bemhtml.js')).pipe(bemhtml({ elemJsInstances: true }))
                )
                    .pipe(concat(bundle.name + '.min.js'))
                    .pipe(gulpif(isProd, uglify())),
            tmpls: bundle =>