jupyterlab-emrys/lib/console/history.js

A computational environment for Jupyter. Powered by Emrys

// Copyright (c) Jupyter Development Team.
// Distributed under the terms of the Modified BSD License.
"use strict";
var phosphor_signaling_1 = require('phosphor-signaling');
/**
 * A console history manager object.
 */
var ConsoleHistory = (function () {
    /**
     * Construct a new console history object.
     */
    function ConsoleHistory(kernel) {
        this._cursor = 0;
        this._history = null;
        this._kernel = null;
        this._history = [];
        if (kernel) {
            this.kernel = kernel;
        }
    }
    Object.defineProperty(ConsoleHistory.prototype, "isDisposed", {
        /**
         * Get whether the console history manager is disposed.
         *
         * #### Notes
         * This is a read-only property.
         */
        get: function () {
            return this._history === null;
        },
        enumerable: true,
        configurable: true
    });
    Object.defineProperty(ConsoleHistory.prototype, "kernel", {
        /**
         * The current kernel supplying navigation history.
         */
        get: function () {
            return this._kernel;
        },
        set: function (newValue) {
            var _this = this;
            if (newValue === this._kernel) {
                return;
            }
            var contents = Private.initialRequest;
            this._kernel = newValue;
            this._kernel.history(contents).then(function (value) {
                _this._history = [];
                var last = '';
                var current = '';
                for (var i = 0; i < value.content.history.length; i++) {
                    // History entries have the shape:
                    // [session: number, line: number, input: string]
                    // Contiguous duplicates are stripped out of the API response.
                    current = value.content.history[i][2];
                    if (current !== last) {
                        _this._history.push(last = current);
                    }
                }
                // Reset the history navigation cursor back to the bottom.
                _this._cursor = _this._history.length;
            });
        },
        enumerable: true,
        configurable: true
    });
    /**
     * Get the previous item in the console history.
     *
     * @returns A Promise for console command text or `undefined` if unavailable.
     */
    ConsoleHistory.prototype.back = function () {
        var content = this._history[--this._cursor];
        this._cursor = Math.max(0, this._cursor);
        return Promise.resolve(content);
    };
    /**
     * Dispose of the resources held by the console history manager.
     */
    ConsoleHistory.prototype.dispose = function () {
        if (this.isDisposed) {
            return;
        }
        phosphor_signaling_1.clearSignalData(this);
        this._history.length = 0;
        this._history = null;
    };
    /**
     * Get the next item in the console history.
     *
     * @returns A Promise for console command text or `undefined` if unavailable.
     */
    ConsoleHistory.prototype.forward = function () {
        var content = this._history[++this._cursor];
        this._cursor = Math.min(this._history.length, this._cursor);
        return Promise.resolve(content);
    };
    /**
     * Add a new item to the bottom of history.
     *
     * @param item The item being added to the bottom of history.
     *
     * #### Notes
     * If the item being added is undefined or empty, it is ignored. If the item
     * being added is the same as the last item in history, it is ignored as well
     * so that the console's history will consist of no contiguous repetitions.
     * This behavior varies from some shells, but the Jupyter Qt Console is
     * implemented this way.
     */
    ConsoleHistory.prototype.push = function (item) {
        if (item && item !== this._history[this._history.length - 1]) {
            this._history.push(item);
        }
        // Reset the history navigation cursor back to the bottom.
        this._cursor = this._history.length;
    };
    return ConsoleHistory;
}());
exports.ConsoleHistory = ConsoleHistory;
/**
 * A namespace for private data.
 */
var Private;
(function (Private) {
    Private.initialRequest = {
        output: false,
        raw: true,
        hist_access_type: 'tail',
        n: 500
    };
})(Private || (Private = {}));