Settings getting cleared when updating them using API

[tsalinger]

Issue Type: Bug

1. Create an extension with 'yo code' and paste in the code at the end of this issue
2. Switch to a light theme.
3. Activate the extension and CTRL+Tab multiple times to another open file in the project while the settings are being imported.
4. Notice how the user settings are temporarily lost and the dark theme is used again, although the users settings still show the light theme.

Observations:
The accessibilitySupport prompt popups shortly before it switches to the dark theme
Sometimes only a restart of VS Code gets the light theme back.

'use strict';

import * as vscode from 'vscode';

export function activate(context: vscode.ExtensionContext) {
    let disposable = vscode.commands.registerCommand('extension.importSettings', () => {
        const config: vscode.WorkspaceConfiguration = vscode.workspace.getConfiguration();
        Object.keys(settings).forEach(key => {
            config.update(key, settings[key], vscode.ConfigurationTarget.Global)
        })
    });

    context.subscriptions.push(disposable);
}

export function deactivate() {
}


var settings: { [s: string]: any; } = {
    "files.autoSave": "off",
    "editor.fontSize": 14,
    "editor.fontFamily": "Consolas, 'Courier New', monospace",
    "editor.tabSize": 4,
    "editor.renderWhitespace": "none",
    "editor.cursorStyle": "line",
    "editor.multiCursorModifier": "alt",
    "editor.insertSpaces": true,
    "editor.wordWrap": "off",
    "diffEditor.ignoreTrimWhitespace": true,
    "diffEditor.renderIndicators": true,
    "diffEditor.renderSideBySide": true,
    "editor.acceptSuggestionOnCommitCharacter": true,
    "editor.acceptSuggestionOnEnter": "on",
    "editor.autoClosingBrackets": true,
    "editor.autoIndent": true,
    "editor.codeLens": true,
    "editor.colorDecorators": true,
    "editor.cursorBlinking": "blink",
    "editor.cursorWidth": 0,
    "editor.detectIndentation": true,
    "editor.dragAndDrop": true,
    "editor.emptySelectionClipboard": true,
    "editor.find.autoFindInSelection": false,
    "editor.find.seedSearchStringFromSelection": true,
    "editor.folding": true,
    "editor.foldingStrategy": "auto",
    "editor.fontLigatures": false,
    "editor.fontWeight": "normal",
    "editor.formatOnPaste": false,
    "editor.formatOnSave": false,
    "editor.formatOnSaveTimeout": 750,
    "editor.formatOnType": false,
    "editor.glyphMargin": true,
    "editor.hideCursorInOverviewRuler": false,
    "editor.letterSpacing": 0,
    "editor.lightbulb.enabled": true,
    "editor.lineHeight": 0,
    "editor.lineNumbers": "on",
    "editor.links": true,
    "editor.matchBrackets": true,
    "editor.minimap.enabled": true,
    "editor.minimap.maxColumn": 120,
    "editor.minimap.renderCharacters": true,
    "editor.minimap.showSlider": "mouseover",
    "editor.minimap.side": "right",
    "editor.mouseWheelScrollSensitivity": 1,
    "editor.mouseWheelZoom": false,
    "editor.occurrencesHighlight": true,
    "editor.overviewRulerBorder": true,
    "editor.overviewRulerLanes": 3,
    "editor.parameterHints": true,
    "editor.quickSuggestionsDelay": 10,
    "editor.renderControlCharacters": false,
    "editor.renderIndentGuides": true,
    "editor.renderLineHighlight": "line",
    "editor.roundedSelection": true,
    "editor.rulers": [],
    "editor.scrollBeyondLastLine": true,
    "editor.selectionHighlight": true,
    "editor.showFoldingControls": "mouseover",
    "editor.smoothScrolling": false,
    "editor.snippetSuggestions": "inline",
    "editor.stablePeek": false,
    "editor.suggestFontSize": 0,
    "editor.suggestLineHeight": 0,
    "editor.suggestOnTriggerCharacters": true,
    "editor.suggestSelection": "recentlyUsed",
    "editor.tabCompletion": false,
    "editor.tokenColorCustomizations": {},
    "editor.trimAutoWhitespace": true,
    "editor.useTabStops": true,
    "editor.wordBasedSuggestions": true,
    "editor.wordSeparators": "`~!@#$%^&*()-=+[{]}\\|;:'\",.<>/?",
    "editor.wordWrapColumn": 80,
    "editor.wrappingIndent": "same",
    "javascript.format.enable": true,
    "javascript.format.insertSpaceAfterCommaDelimiter": true,
    "javascript.format.insertSpaceAfterConstructor": false,
    "javascript.format.insertSpaceAfterFunctionKeywordForAnonymousFunctions": true,
    "javascript.format.insertSpaceAfterKeywordsInControlFlowStatements": true,
    "javascript.format.insertSpaceAfterOpeningAndBeforeClosingJsxExpressionBraces": false,
    "javascript.format.insertSpaceAfterOpeningAndBeforeClosingNonemptyBraces": true,
    "javascript.format.insertSpaceAfterOpeningAndBeforeClosingNonemptyBrackets": false,
    "javascript.format.insertSpaceAfterOpeningAndBeforeClosingNonemptyParenthesis": false,
    "javascript.format.insertSpaceAfterOpeningAndBeforeClosingTemplateStringBraces": false,
    "javascript.format.insertSpaceAfterSemicolonInForStatements": true,
    "javascript.format.insertSpaceBeforeAndAfterBinaryOperators": true,
    "javascript.format.insertSpaceBeforeFunctionParenthesis": false,
    "javascript.format.placeOpenBraceOnNewLineForControlBlocks": false,
    "javascript.format.placeOpenBraceOnNewLineForFunctions": false,
    "javascript.implicitProjectConfig.checkJs": false,
    "javascript.implicitProjectConfig.experimentalDecorators": false,
    "javascript.nameSuggestions": true,
    "javascript.referencesCodeLens.enabled": false,
    "javascript.suggestionActions.enabled": true,
    "javascript.validate.enable": true,
    "jsDocCompletion.enabled": true,
    "typescript.autoImportSuggestions.enabled": true,
    "typescript.check.npmIsInstalled": true,
    "typescript.disableAutomaticTypeAcquisition": false,
    "typescript.experimental.syntaxFolding": true,
    "typescript.format.enable": true,
    "typescript.format.insertSpaceAfterCommaDelimiter": true,
    "typescript.format.insertSpaceAfterConstructor": false,
    "typescript.format.insertSpaceAfterFunctionKeywordForAnonymousFunctions": true,
    "typescript.format.insertSpaceAfterKeywordsInControlFlowStatements": true,
    "typescript.format.insertSpaceAfterOpeningAndBeforeClosingJsxExpressionBraces": false,
    "typescript.format.insertSpaceAfterOpeningAndBeforeClosingNonemptyBraces": true,
    "typescript.format.insertSpaceAfterOpeningAndBeforeClosingNonemptyBrackets": false,
    "typescript.format.insertSpaceAfterOpeningAndBeforeClosingNonemptyParenthesis": false,
    "typescript.format.insertSpaceAfterOpeningAndBeforeClosingTemplateStringBraces": false,
    "typescript.format.insertSpaceAfterSemicolonInForStatements": true,
    "typescript.format.insertSpaceAfterTypeAssertion": false,
    "typescript.format.insertSpaceBeforeAndAfterBinaryOperators": true,
    "typescript.format.insertSpaceBeforeFunctionParenthesis": false,
    "typescript.format.placeOpenBraceOnNewLineForControlBlocks": false,
    "typescript.format.placeOpenBraceOnNewLineForFunctions": false,
    "typescript.implementationsCodeLens.enabled": false,
    "typescript.locale": null,
    "typescript.npm": null,
    "typescript.quickSuggestionsForPaths": true,
    "typescript.referencesCodeLens.enabled": false,
    "typescript.reportStyleChecksAsWarnings": true,
    "typescript.suggestionActions.enabled": true,
    "typescript.tsc.autoDetect": "on",
    "typescript.tsdk": null,
    "typescript.tsserver.log": "off",
    "typescript.tsserver.pluginPaths": [],
    "typescript.tsserver.trace": "off",
    "typescript.useCodeSnippetsOnMethodSuggest": false,
    "typescript.validate.enable": true
}

VS Code version: Code - Insiders 1.23.0-insider (fe9d953, 2018-04-12T05:17:00.120Z)
OS version: Windows_NT x64 10.0.16299

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-4600U CPU @ 2.10GHz (4 x 2694)
GPU Status	2d_canvas: enabled flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled multiple_raster_threads: enabled_on native_gpu_memory_buffers: disabled_software rasterization: disabled_software video_decode: enabled video_encode: enabled vpx_decode: unavailable_software webgl: enabled webgl2: enabled
Memory (System)	7.88GB (3.95GB free)
Process Argv	C:\Program Files\Microsoft VS Code Insiders\Code - Insiders.exe
Screen Reader	yes
VM	0%

Extensions (13)

Extension	Author (truncated)	Version
vscode-css-formatter	aes	1.0.1
numbered-bookmarks	ale	0.11.1
regex	chr	0.1.0
vscode-eslint	dba	1.4.8
gitlens	eam	8.2.1
tslint	eg2	1.0.28
vsc-material-theme	Equ	1.5.1
python	ms-	2018.3.1
debugger-for-chrome	msj	4.3.0
gitlink	qez	0.4.2
ayu	tea	0.14.0
vscode-todo-highlight	way	0.5.12
markdown-pdf	yza	0.1.8

(3 theme extensions excluded)

[sandy081]

@tsalinger I am not able to reproduce this on insiders also when running from dev. Can you please try disabling extensions?

[tsalinger]

@sandy081 I can still reproduce this in the latest insiders with all extensions disabled.
Maybe the key is to have the following user settings to start from:

{
    "editor.accessibilitySupport": "off",
    "files.autoSave": "onWindowChange",
    "workbench.colorTheme": "Default Light+",
}

Also make sure to use "files.autoSave": "onWindowChange" in the settings arrray.

The bug seems to appear less frequently when the VS Code window is not maximized.

[sandy081]

@tsalinger No luck. May be I will sit with you tomorrow and look into it on your machine

[usernamehw]

I've seen a somewhat similar issue. On a laptop it switches to the default dark theme (for about 10ms) and then back at random (cannot reproduce reliably).

There is a comment on a linked issue:

During the import process the settings might be reverted to an empty object for an instant. This leads to a flickering from a light theme to the default dark theme and back. Additionally, the 'screen-reader optimized' message box might be visible for an instant.

Does that mean that the reason of this flickering is some extension or a problem with settings file or API?

[sandy081]

@usernamehw We investigated on this issue and found out that this is happening because of non-atomic nature of write and read. If a setting is being written into the file and the file is being read at the same time, read is returning empty contents. This can happen when multiple updates are happening.

[bcroq]

I just lost my user settings a few seconds after starting code 😞

VS Code version: 1.51.0 upgraded 4 days ago
OS version: Ubuntu 20.04

[jaredcwhite]

I've seen this multiple times now via background software updates. Grabbing my settings.json from backup for the third time… :'(

(yes I should probably turn on Settings Sync, but IMHO that's not an adequate solution to this problem…)

[sandy081]

Noted, I have added some fixes recently which might prevent this. Can you please try with our recent insiders and see if you see this issue yet?