Source/WebInspectorUI/UserInterface/Controllers/JavaScriptLogViewController.js - external/github.com/WebKit/webkit - Git at Google

 /*
  * Copyright (C) 2013 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  * THE POSSIBILITY OF SUCH DAMAGE.
  */

 WI.JavaScriptLogViewController = class JavaScriptLogViewController extends WI.Object
 {
     constructor(element, scrollElement, textPrompt, delegate, historySettingIdentifier)
     {
         super();

         console.assert(textPrompt instanceof WI.ConsolePrompt);
         console.assert(historySettingIdentifier);

         this._element = element;
         this._scrollElement = scrollElement;

         this._promptHistorySetting = new WI.Setting(historySettingIdentifier, null);

         this._prompt = textPrompt;
         this._prompt.delegate = this;
         this._prompt.history = this._promptHistorySetting.value;

         this.delegate = delegate;

         this._cleared = true;
         this._previousMessageView = null;
         this._lastConsoleMessageViewForTarget = new WeakMap;
         this._lastCommitted = {text: "", special: false};
         this._repeatCountWasInterrupted = false;

         this._sessions = [];
         this._currentSessionOrGroup = null;

         this._failedSourceMapsGroup = null;

         this.messagesAlternateClearKeyboardShortcut = new WI.KeyboardShortcut(WI.KeyboardShortcut.Modifier.Control, "L", this.requestClearMessages.bind(this), this._element);

         this._messagesFindNextKeyboardShortcut = new WI.KeyboardShortcut(WI.KeyboardShortcut.Modifier.CommandOrControl, "G", this._handleFindNextShortcut.bind(this), this._element);
         this._messagesFindPreviousKeyboardShortcut = new WI.KeyboardShortcut(WI.KeyboardShortcut.Modifier.CommandOrControl | WI.KeyboardShortcut.Modifier.Shift, "G", this._handleFindPreviousShortcut.bind(this), this._element);

         this._promptAlternateClearKeyboardShortcut = new WI.KeyboardShortcut(WI.KeyboardShortcut.Modifier.Control, "L", this.requestClearMessages.bind(this), this._prompt.element);
         this._promptFindNextKeyboardShortcut = new WI.KeyboardShortcut(WI.KeyboardShortcut.Modifier.CommandOrControl, "G", this._handleFindNextShortcut.bind(this), this._prompt.element);
         this._promptFindPreviousKeyboardShortcut = new WI.KeyboardShortcut(WI.KeyboardShortcut.Modifier.CommandOrControl | WI.KeyboardShortcut.Modifier.Shift, "G", this._handleFindPreviousShortcut.bind(this), this._prompt.element);

         WI.settings.showConsoleMessageTimestamps.addEventListener(WI.Setting.Event.Changed, this._handleShowConsoleMessageTimestampsSettingChanged, this);

         this._pendingMessagesForSessionOrGroup = new Map;
         this._scheduledRenderIdentifier = 0;

         this.startNewSession();
     }

     // Public

     clear()
     {
         this._cleared = true;

         const clearPreviousSessions = true;
         this.startNewSession(clearPreviousSessions, {newSessionReason: WI.ConsoleSession.NewSessionReason.ConsoleCleared});
     }

     startNewSession(clearPreviousSessions = false, data = {})
     {
         if (clearPreviousSessions) {
             this._pendingMessagesForSessionOrGroup.clear();

             if (this._sessions.length) {
                 for (let session of this._sessions)
                     session.element.remove();

                 this._sessions = [];
                 this._currentSessionOrGroup = null;
             }
         }

         // First session shows the time when the console was opened.
         if (!this._sessions.length)
             data.timestamp = Date.now();

         let lastSession = this._sessions.lastValue;

         // Remove empty session.
         if (lastSession && !lastSession.hasMessages() && !this._pendingMessagesForSessionOrGroup.has(lastSession)) {
             this._sessions.pop();
             lastSession.element.remove();
         }

         let consoleSession = new WI.ConsoleSession(data);

         this._previousMessageView = null;
         this._lastConsoleMessageViewForTarget = new WeakMap;
         this._lastCommitted = {text: "", special: false};
         this._repeatCountWasInterrupted = false;

         this._sessions.push(consoleSession);
         this._currentSessionOrGroup = consoleSession;

         this._failedSourceMapsGroup = null;

         this._element.appendChild(consoleSession.element);

         // Make sure the new session is visible.
         consoleSession.element.scrollIntoView();
     }

     appendImmediateExecutionWithResult(text, result, {addSpecialUserLogClass, shouldRevealConsole, handleClick} = {})
     {
         console.assert(result instanceof WI.RemoteObject);

         if (this._lastCommitted.text !== text || this._lastCommitted.special !== addSpecialUserLogClass) {
             let classNames = [];
             if (addSpecialUserLogClass)
                 classNames.push("special-user-log");

             let commandMessageView = new WI.ConsoleCommandView(text, {classNames, handleClick});
             this._appendConsoleCommandView(commandMessageView);
             this._lastCommitted = {text, special: addSpecialUserLogClass};
         }

         function saveResultCallback(savedResultIndex)
         {
             let commandResultMessage = new WI.ConsoleCommandResultMessage(result.target, result, false, savedResultIndex, { shouldRevealConsole });
             let commandResultMessageView = new WI.ConsoleMessageView(commandResultMessage);
             this._appendConsoleMessageView(commandResultMessageView, true);
         }

         WI.runtimeManager.saveResult(result, saveResultCallback.bind(this));
     }

     appendConsoleMessage(consoleMessage)
     {
         let consoleMessageView = new WI.ConsoleMessageView(consoleMessage);
         this._appendConsoleMessageView(consoleMessageView);
         return consoleMessageView;
     }

     updatePreviousMessageRepeatCount(target, count, timestamp)
     {
         let previousMessageView = this._previousMessageView;
         console.assert(previousMessageView);
         if (!previousMessageView)
             return false;

         if (previousMessageView.message.target !== target) {
             previousMessageView = this._lastConsoleMessageViewForTarget.get(target);
             console.assert(previousMessageView);
             if (!previousMessageView)
                 return false;
             let messageView = this.appendConsoleMessage(previousMessageView.message);
             messageView.timestamp = timestamp;
             messageView[WI.JavaScriptLogViewController.IgnoredRepeatCount] = count - 1;
             messageView.repeatCount = 1;
             this._repeatCountWasInterrupted = false;
             return true;
         }

         let previousIgnoredCount = previousMessageView[WI.JavaScriptLogViewController.IgnoredRepeatCount] || 0;
         let previousVisibleCount = previousMessageView.repeatCount;

         if (!this._repeatCountWasInterrupted) {
             previousMessageView.repeatCount = count - previousIgnoredCount;
             previousMessageView.timestamp = timestamp;
             return true;
         }

         let consoleMessage = previousMessageView.message;
         let duplicatedConsoleMessageView = new WI.ConsoleMessageView(consoleMessage);
         duplicatedConsoleMessageView[WI.JavaScriptLogViewController.IgnoredRepeatCount] = previousIgnoredCount + previousVisibleCount;
         duplicatedConsoleMessageView.repeatCount = 1;
         duplicatedConsoleMessageView.timestamp = timestamp;
         this._appendConsoleMessageView(duplicatedConsoleMessageView);

         return true;
     }

     isScrolledToBottom()
     {
         // Lie about being scrolled to the bottom if we have a pending request to scroll to the bottom soon.
         return this._scrollToBottomTimeout || this._scrollElement.isScrolledToBottom();
     }

     scrollToBottom()
     {
         if (this._scrollToBottomTimeout)
             return;

         function delayedWork()
         {
             this._scrollToBottomTimeout = null;
             this._scrollElement.scrollTop = this._scrollElement.scrollHeight;
         }

         // Don't scroll immediately so we are not causing excessive layouts when there
         // are many messages being added at once.
         this._scrollToBottomTimeout = setTimeout(delayedWork.bind(this), 0);
     }

     requestClearMessages()
     {
         WI.consoleManager.requestClearMessages();
     }

     // Protected

     consolePromptHistoryDidChange(prompt)
     {
         this._promptHistorySetting.value = this._prompt.history;
     }

     consolePromptShouldCommitText(prompt, text, cursorIsAtLastPosition, handler)
     {
         // Always commit the text if we are not at the last position.
         if (!cursorIsAtLastPosition) {
             handler(true);
             return;
         }

         function parseFinished(error, result, message, range)
         {
             handler(result !== InspectorBackend.Enum.Runtime.SyntaxErrorType.Recoverable);
         }

         WI.runtimeManager.activeExecutionContext.target.RuntimeAgent.parse(text, parseFinished.bind(this));
     }

     consolePromptTextCommitted(prompt, text)
     {
         console.assert(text);

         if (this._lastCommitted.text !== text || this._lastCommitted.special) {
             let commandMessageView = new WI.ConsoleCommandView(text);
             this._appendConsoleCommandView(commandMessageView);
             this._lastCommitted = {text, special: false};
         }

         function printResult(result, wasThrown, savedResultIndex)
         {
             if (!result || this._cleared)
                 return;

             let commandResultMessage = new WI.ConsoleCommandResultMessage(result.target, result, wasThrown, savedResultIndex, { shouldRevealConsole: true });
             let commandResultMessageView = new WI.ConsoleMessageView(commandResultMessage);
             this._appendConsoleMessageView(commandResultMessageView, true);
         }

         let options = {
             objectGroup: WI.RuntimeManager.ConsoleObjectGroup,
             includeCommandLineAPI: true,
             doNotPauseOnExceptionsAndMuteConsole: false,
             returnByValue: false,
             generatePreview: true,
             saveResult: true,
             emulateUserGesture: WI.settings.emulateInUserGesture.value,
             sourceURLAppender: appendWebInspectorConsoleEvaluationSourceURL,
         };

         WI.javaScriptRuntimeCompletionProvider.clearCachedPropertyNames();

         WI.runtimeManager.evaluateInInspectedWindow(text, options, printResult.bind(this));
     }

     // Private

     _handleFindNextShortcut()
     {
         this.delegate.highlightNextSearchMatch();
     }

     _handleFindPreviousShortcut()
     {
         this.delegate.highlightPreviousSearchMatch();
     }

     _appendConsoleMessageView(messageView, repeatCountWasInterrupted)
     {
         console.assert(messageView instanceof WI.ConsoleMessageView);

         this._addToPendingMessages(messageView);
         this._cleared = false;
         this._repeatCountWasInterrupted = repeatCountWasInterrupted || false;

         let message = messageView.message;

         if (!repeatCountWasInterrupted) {
             this._previousMessageView = messageView;
             this._lastConsoleMessageViewForTarget.set(message.target, messageView);
         }

         if (message.source !== WI.ConsoleMessage.MessageSource.JS)
             this._lastCommitted = {text: "", special: false};

         if (WI.consoleContentView.isAttached)
             this.renderPendingMessagesSoon();

         if (!WI.isShowingConsoleTab() && message.shouldRevealConsole)
             WI.showSplitConsole();
     }

     _appendConsoleCommandView(commandView)
     {
         console.assert(commandView instanceof WI.ConsoleCommandView);

         this._addToPendingMessages(commandView);
         this._cleared = false;
         this._repeatCountWasInterrupted = true;

         if (WI.consoleContentView.isAttached)
             this.renderPendingMessagesSoon();
     }

     _addToPendingMessages(messageView)
     {
         let pendingMessagesForSession = this._pendingMessagesForSessionOrGroup.getOrInsert(this._currentSessionOrGroup, []);
         pendingMessagesForSession.push(messageView);
         this._pendingMessagesForSessionOrGroup.set(this._currentSessionOrGroup, pendingMessagesForSession);
     }

     renderPendingMessages()
     {
         if (this._scheduledRenderIdentifier) {
             cancelAnimationFrame(this._scheduledRenderIdentifier);
             this._scheduledRenderIdentifier = 0;
         }

         if (!this._pendingMessagesForSessionOrGroup.size)
             return;

         let wasScrolledToBottom = this.isScrolledToBottom();
         let savedCurrentConsoleGroup = this._currentSessionOrGroup;
         let lastMessageView = null;

         const maxMessagesPerFrame = 100;
         let renderedMessages = 0;
         for (let [session, messages] of this._pendingMessagesForSessionOrGroup) {
             this._currentSessionOrGroup = session;

             let messagesToRender = messages.splice(0, maxMessagesPerFrame - renderedMessages);
             for (let message of messagesToRender) {
                 message.render();
                 this._didRenderConsoleMessageView(message);
             }

             lastMessageView = messagesToRender.lastValue;

             if (!messages.length)
                 this._pendingMessagesForSessionOrGroup.delete(session);

             renderedMessages += messagesToRender.length;
             if (renderedMessages >= maxMessagesPerFrame)
                 break;
         }

         this._currentSessionOrGroup = savedCurrentConsoleGroup;

         this._handleShowConsoleMessageTimestampsSettingChanged();

         if (wasScrolledToBottom || lastMessageView instanceof WI.ConsoleCommandView || lastMessageView.message.type === WI.ConsoleMessage.MessageType.Result || lastMessageView.message.type === WI.ConsoleMessage.MessageType.Image)
             this.scrollToBottom();

         WI.quickConsole.needsLayout();

         if (this._pendingMessagesForSessionOrGroup.size)
             this.renderPendingMessagesSoon();
     }

     renderPendingMessagesSoon()
     {
         if (this._scheduledRenderIdentifier)
             return;

         this._scheduledRenderIdentifier = requestAnimationFrame(() => this.renderPendingMessages());
     }

     _didRenderConsoleMessageView(messageView)
     {
         let type = messageView instanceof WI.ConsoleCommandView ? null : messageView.message.type;
         if (type === WI.ConsoleMessage.MessageType.EndGroup) {
             let parentGroup = this._currentSessionOrGroup.parentGroup;
             if (parentGroup)
                 this._currentSessionOrGroup = parentGroup;
         } else {
             if (type === WI.ConsoleMessage.MessageType.StartGroup || type === WI.ConsoleMessage.MessageType.StartGroupCollapsed) {
                 let group = new WI.ConsoleGroup(this._currentSessionOrGroup);
                 let groupElement = group.render(messageView);
                 this._currentSessionOrGroup.append(groupElement);
                 this._currentSessionOrGroup = group;
             } else
                 this._currentSessionOrGroup.addMessageView(messageView);

             // FIXME: <https://webkit.org/b/264490> (Improve failed SourceMap error grouping to avoid unnecessary work)
             if (WI.settings.experimentalGroupSourceMapErrors.value && WI.consoleManager.failedSourceMapConsoleMessages.has(messageView.message))
                 this._addConsoleMessageToConsoleSourceMapErrorGroup(messageView);
         }

         if (this.delegate && typeof this.delegate.didAppendConsoleMessageView === "function")
             this.delegate.didAppendConsoleMessageView(messageView);
     }

     _addConsoleMessageToConsoleSourceMapErrorGroup(messageView)
     {
         if (!this._firstSourceMapErrorMessageView) {
             this._firstSourceMapErrorMessageView = messageView;
             return;
         }

         if (!this._failedSourceMapsGroup) {
             let currentTopLevelSession = this._sessions.lastValue;
             this._failedSourceMapsGroup = new WI.ConsoleSourceMapMessageGroup;
             currentTopLevelSession.append(this._failedSourceMapsGroup.element);
             this._failedSourceMapsGroup.addMessageView(this._firstSourceMapErrorMessageView);
         }

         this._failedSourceMapsGroup.addMessageView(messageView);
     }

     _handleShowConsoleMessageTimestampsSettingChanged()
     {
         this._currentSessionOrGroup.element.classList.toggle("timestamps-visible", WI.settings.showConsoleMessageTimestamps.value);
     }
 };

 WI.JavaScriptLogViewController.CachedPropertiesDuration = 30_000;
 WI.JavaScriptLogViewController.IgnoredRepeatCount = Symbol("ignored-repeat-count");
	/*
	* Copyright (C) 2013 Apple Inc. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
	* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
	* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	* THE POSSIBILITY OF SUCH DAMAGE.
	*/

	WI.JavaScriptLogViewController = class JavaScriptLogViewController extends WI.Object
	{
	constructor(element, scrollElement, textPrompt, delegate, historySettingIdentifier)
	{
	super();

	console.assert(textPrompt instanceof WI.ConsolePrompt);
	console.assert(historySettingIdentifier);

	this._element = element;
	this._scrollElement = scrollElement;

	this._promptHistorySetting = new WI.Setting(historySettingIdentifier, null);

	this._prompt = textPrompt;
	this._prompt.delegate = this;
	this._prompt.history = this._promptHistorySetting.value;

	this.delegate = delegate;

	this._cleared = true;
	this._previousMessageView = null;
	this._lastConsoleMessageViewForTarget = new WeakMap;
	this._lastCommitted = {text: "", special: false};
	this._repeatCountWasInterrupted = false;

	this._sessions = [];
	this._currentSessionOrGroup = null;

	this._failedSourceMapsGroup = null;

	this.messagesAlternateClearKeyboardShortcut = new WI.KeyboardShortcut(WI.KeyboardShortcut.Modifier.Control, "L", this.requestClearMessages.bind(this), this._element);

	this._messagesFindNextKeyboardShortcut = new WI.KeyboardShortcut(WI.KeyboardShortcut.Modifier.CommandOrControl, "G", this._handleFindNextShortcut.bind(this), this._element);
	this._messagesFindPreviousKeyboardShortcut = new WI.KeyboardShortcut(WI.KeyboardShortcut.Modifier.CommandOrControl \| WI.KeyboardShortcut.Modifier.Shift, "G", this._handleFindPreviousShortcut.bind(this), this._element);

	this._promptAlternateClearKeyboardShortcut = new WI.KeyboardShortcut(WI.KeyboardShortcut.Modifier.Control, "L", this.requestClearMessages.bind(this), this._prompt.element);
	this._promptFindNextKeyboardShortcut = new WI.KeyboardShortcut(WI.KeyboardShortcut.Modifier.CommandOrControl, "G", this._handleFindNextShortcut.bind(this), this._prompt.element);
	this._promptFindPreviousKeyboardShortcut = new WI.KeyboardShortcut(WI.KeyboardShortcut.Modifier.CommandOrControl \| WI.KeyboardShortcut.Modifier.Shift, "G", this._handleFindPreviousShortcut.bind(this), this._prompt.element);

	WI.settings.showConsoleMessageTimestamps.addEventListener(WI.Setting.Event.Changed, this._handleShowConsoleMessageTimestampsSettingChanged, this);

	this._pendingMessagesForSessionOrGroup = new Map;
	this._scheduledRenderIdentifier = 0;

	this.startNewSession();
	}

	// Public

	clear()
	{
	this._cleared = true;

	const clearPreviousSessions = true;
	this.startNewSession(clearPreviousSessions, {newSessionReason: WI.ConsoleSession.NewSessionReason.ConsoleCleared});
	}

	startNewSession(clearPreviousSessions = false, data = {})
	{
	if (clearPreviousSessions) {
	this._pendingMessagesForSessionOrGroup.clear();

	if (this._sessions.length) {
	for (let session of this._sessions)
	session.element.remove();

	this._sessions = [];
	this._currentSessionOrGroup = null;
	}
	}

	// First session shows the time when the console was opened.
	if (!this._sessions.length)
	data.timestamp = Date.now();

	let lastSession = this._sessions.lastValue;

	// Remove empty session.
	if (lastSession && !lastSession.hasMessages() && !this._pendingMessagesForSessionOrGroup.has(lastSession)) {
	this._sessions.pop();
	lastSession.element.remove();
	}

	let consoleSession = new WI.ConsoleSession(data);

	this._previousMessageView = null;
	this._lastConsoleMessageViewForTarget = new WeakMap;
	this._lastCommitted = {text: "", special: false};
	this._repeatCountWasInterrupted = false;

	this._sessions.push(consoleSession);
	this._currentSessionOrGroup = consoleSession;

	this._failedSourceMapsGroup = null;

	this._element.appendChild(consoleSession.element);

	// Make sure the new session is visible.
	consoleSession.element.scrollIntoView();
	}

	appendImmediateExecutionWithResult(text, result, {addSpecialUserLogClass, shouldRevealConsole, handleClick} = {})
	{
	console.assert(result instanceof WI.RemoteObject);

	if (this._lastCommitted.text !== text \|\| this._lastCommitted.special !== addSpecialUserLogClass) {
	let classNames = [];
	if (addSpecialUserLogClass)
	classNames.push("special-user-log");

	let commandMessageView = new WI.ConsoleCommandView(text, {classNames, handleClick});
	this._appendConsoleCommandView(commandMessageView);
	this._lastCommitted = {text, special: addSpecialUserLogClass};
	}

	function saveResultCallback(savedResultIndex)
	{
	let commandResultMessage = new WI.ConsoleCommandResultMessage(result.target, result, false, savedResultIndex, { shouldRevealConsole });
	let commandResultMessageView = new WI.ConsoleMessageView(commandResultMessage);
	this._appendConsoleMessageView(commandResultMessageView, true);
	}

	WI.runtimeManager.saveResult(result, saveResultCallback.bind(this));
	}

	appendConsoleMessage(consoleMessage)
	{
	let consoleMessageView = new WI.ConsoleMessageView(consoleMessage);
	this._appendConsoleMessageView(consoleMessageView);
	return consoleMessageView;
	}

	updatePreviousMessageRepeatCount(target, count, timestamp)
	{
	let previousMessageView = this._previousMessageView;
	console.assert(previousMessageView);
	if (!previousMessageView)
	return false;

	if (previousMessageView.message.target !== target) {
	previousMessageView = this._lastConsoleMessageViewForTarget.get(target);
	console.assert(previousMessageView);
	if (!previousMessageView)
	return false;
	let messageView = this.appendConsoleMessage(previousMessageView.message);
	messageView.timestamp = timestamp;
	messageView[WI.JavaScriptLogViewController.IgnoredRepeatCount] = count - 1;
	messageView.repeatCount = 1;
	this._repeatCountWasInterrupted = false;
	return true;
	}

	let previousIgnoredCount = previousMessageView[WI.JavaScriptLogViewController.IgnoredRepeatCount] \|\| 0;
	let previousVisibleCount = previousMessageView.repeatCount;

	if (!this._repeatCountWasInterrupted) {
	previousMessageView.repeatCount = count - previousIgnoredCount;
	previousMessageView.timestamp = timestamp;
	return true;
	}

	let consoleMessage = previousMessageView.message;
	let duplicatedConsoleMessageView = new WI.ConsoleMessageView(consoleMessage);
	duplicatedConsoleMessageView[WI.JavaScriptLogViewController.IgnoredRepeatCount] = previousIgnoredCount + previousVisibleCount;
	duplicatedConsoleMessageView.repeatCount = 1;
	duplicatedConsoleMessageView.timestamp = timestamp;
	this._appendConsoleMessageView(duplicatedConsoleMessageView);

	return true;
	}

	isScrolledToBottom()
	{
	// Lie about being scrolled to the bottom if we have a pending request to scroll to the bottom soon.
	return this._scrollToBottomTimeout \|\| this._scrollElement.isScrolledToBottom();
	}

	scrollToBottom()
	{
	if (this._scrollToBottomTimeout)
	return;

	function delayedWork()
	{
	this._scrollToBottomTimeout = null;
	this._scrollElement.scrollTop = this._scrollElement.scrollHeight;
	}

	// Don't scroll immediately so we are not causing excessive layouts when there
	// are many messages being added at once.
	this._scrollToBottomTimeout = setTimeout(delayedWork.bind(this), 0);
	}

	requestClearMessages()
	{
	WI.consoleManager.requestClearMessages();
	}

	// Protected

	consolePromptHistoryDidChange(prompt)
	{
	this._promptHistorySetting.value = this._prompt.history;
	}

	consolePromptShouldCommitText(prompt, text, cursorIsAtLastPosition, handler)
	{
	// Always commit the text if we are not at the last position.
	if (!cursorIsAtLastPosition) {
	handler(true);
	return;
	}

	function parseFinished(error, result, message, range)
	{
	handler(result !== InspectorBackend.Enum.Runtime.SyntaxErrorType.Recoverable);
	}

	WI.runtimeManager.activeExecutionContext.target.RuntimeAgent.parse(text, parseFinished.bind(this));
	}

	consolePromptTextCommitted(prompt, text)
	{
	console.assert(text);

	if (this._lastCommitted.text !== text \|\| this._lastCommitted.special) {
	let commandMessageView = new WI.ConsoleCommandView(text);
	this._appendConsoleCommandView(commandMessageView);
	this._lastCommitted = {text, special: false};
	}

	function printResult(result, wasThrown, savedResultIndex)
	{
	if (!result \|\| this._cleared)
	return;

	let commandResultMessage = new WI.ConsoleCommandResultMessage(result.target, result, wasThrown, savedResultIndex, { shouldRevealConsole: true });
	let commandResultMessageView = new WI.ConsoleMessageView(commandResultMessage);
	this._appendConsoleMessageView(commandResultMessageView, true);
	}

	let options = {
	objectGroup: WI.RuntimeManager.ConsoleObjectGroup,
	includeCommandLineAPI: true,
	doNotPauseOnExceptionsAndMuteConsole: false,
	returnByValue: false,
	generatePreview: true,
	saveResult: true,
	emulateUserGesture: WI.settings.emulateInUserGesture.value,
	sourceURLAppender: appendWebInspectorConsoleEvaluationSourceURL,
	};

	WI.javaScriptRuntimeCompletionProvider.clearCachedPropertyNames();

	WI.runtimeManager.evaluateInInspectedWindow(text, options, printResult.bind(this));
	}

	// Private

	_handleFindNextShortcut()
	{
	this.delegate.highlightNextSearchMatch();
	}

	_handleFindPreviousShortcut()
	{
	this.delegate.highlightPreviousSearchMatch();
	}

	_appendConsoleMessageView(messageView, repeatCountWasInterrupted)
	{
	console.assert(messageView instanceof WI.ConsoleMessageView);

	this._addToPendingMessages(messageView);
	this._cleared = false;
	this._repeatCountWasInterrupted = repeatCountWasInterrupted \|\| false;

	let message = messageView.message;

	if (!repeatCountWasInterrupted) {
	this._previousMessageView = messageView;
	this._lastConsoleMessageViewForTarget.set(message.target, messageView);
	}

	if (message.source !== WI.ConsoleMessage.MessageSource.JS)
	this._lastCommitted = {text: "", special: false};

	if (WI.consoleContentView.isAttached)
	this.renderPendingMessagesSoon();

	if (!WI.isShowingConsoleTab() && message.shouldRevealConsole)
	WI.showSplitConsole();
	}

	_appendConsoleCommandView(commandView)
	{
	console.assert(commandView instanceof WI.ConsoleCommandView);

	this._addToPendingMessages(commandView);
	this._cleared = false;
	this._repeatCountWasInterrupted = true;

	if (WI.consoleContentView.isAttached)
	this.renderPendingMessagesSoon();
	}

	_addToPendingMessages(messageView)
	{
	let pendingMessagesForSession = this._pendingMessagesForSessionOrGroup.getOrInsert(this._currentSessionOrGroup, []);
	pendingMessagesForSession.push(messageView);
	this._pendingMessagesForSessionOrGroup.set(this._currentSessionOrGroup, pendingMessagesForSession);
	}

	renderPendingMessages()
	{
	if (this._scheduledRenderIdentifier) {
	cancelAnimationFrame(this._scheduledRenderIdentifier);
	this._scheduledRenderIdentifier = 0;
	}

	if (!this._pendingMessagesForSessionOrGroup.size)
	return;

	let wasScrolledToBottom = this.isScrolledToBottom();
	let savedCurrentConsoleGroup = this._currentSessionOrGroup;
	let lastMessageView = null;

	const maxMessagesPerFrame = 100;
	let renderedMessages = 0;
	for (let [session, messages] of this._pendingMessagesForSessionOrGroup) {
	this._currentSessionOrGroup = session;

	let messagesToRender = messages.splice(0, maxMessagesPerFrame - renderedMessages);
	for (let message of messagesToRender) {
	message.render();
	this._didRenderConsoleMessageView(message);
	}

	lastMessageView = messagesToRender.lastValue;

	if (!messages.length)
	this._pendingMessagesForSessionOrGroup.delete(session);

	renderedMessages += messagesToRender.length;
	if (renderedMessages >= maxMessagesPerFrame)
	break;
	}

	this._currentSessionOrGroup = savedCurrentConsoleGroup;

	this._handleShowConsoleMessageTimestampsSettingChanged();

	if (wasScrolledToBottom \|\| lastMessageView instanceof WI.ConsoleCommandView \|\| lastMessageView.message.type === WI.ConsoleMessage.MessageType.Result \|\| lastMessageView.message.type === WI.ConsoleMessage.MessageType.Image)
	this.scrollToBottom();

	WI.quickConsole.needsLayout();

	if (this._pendingMessagesForSessionOrGroup.size)
	this.renderPendingMessagesSoon();
	}

	renderPendingMessagesSoon()
	{
	if (this._scheduledRenderIdentifier)
	return;

	this._scheduledRenderIdentifier = requestAnimationFrame(() => this.renderPendingMessages());
	}

	_didRenderConsoleMessageView(messageView)
	{
	let type = messageView instanceof WI.ConsoleCommandView ? null : messageView.message.type;
	if (type === WI.ConsoleMessage.MessageType.EndGroup) {
	let parentGroup = this._currentSessionOrGroup.parentGroup;
	if (parentGroup)
	this._currentSessionOrGroup = parentGroup;
	} else {
	if (type === WI.ConsoleMessage.MessageType.StartGroup \|\| type === WI.ConsoleMessage.MessageType.StartGroupCollapsed) {
	let group = new WI.ConsoleGroup(this._currentSessionOrGroup);
	let groupElement = group.render(messageView);
	this._currentSessionOrGroup.append(groupElement);
	this._currentSessionOrGroup = group;
	} else
	this._currentSessionOrGroup.addMessageView(messageView);

	// FIXME: <https://webkit.org/b/264490> (Improve failed SourceMap error grouping to avoid unnecessary work)
	if (WI.settings.experimentalGroupSourceMapErrors.value && WI.consoleManager.failedSourceMapConsoleMessages.has(messageView.message))
	this._addConsoleMessageToConsoleSourceMapErrorGroup(messageView);
	}

	if (this.delegate && typeof this.delegate.didAppendConsoleMessageView === "function")
	this.delegate.didAppendConsoleMessageView(messageView);
	}

	_addConsoleMessageToConsoleSourceMapErrorGroup(messageView)
	{
	if (!this._firstSourceMapErrorMessageView) {
	this._firstSourceMapErrorMessageView = messageView;
	return;
	}

	if (!this._failedSourceMapsGroup) {
	let currentTopLevelSession = this._sessions.lastValue;
	this._failedSourceMapsGroup = new WI.ConsoleSourceMapMessageGroup;
	currentTopLevelSession.append(this._failedSourceMapsGroup.element);
	this._failedSourceMapsGroup.addMessageView(this._firstSourceMapErrorMessageView);
	}

	this._failedSourceMapsGroup.addMessageView(messageView);
	}

	_handleShowConsoleMessageTimestampsSettingChanged()
	{
	this._currentSessionOrGroup.element.classList.toggle("timestamps-visible", WI.settings.showConsoleMessageTimestamps.value);
	}
	};

	WI.JavaScriptLogViewController.CachedPropertiesDuration = 30_000;
	WI.JavaScriptLogViewController.IgnoredRepeatCount = Symbol("ignored-repeat-count");