Restore the settings to the initial value if they were set before

src/constants.ts

@@ -4,5 +4,5 @@ export const FORMATTING_SETTINGS = [
   'formatOnSave',
   'formatOnType'
 ]
-export const ENABLE_TEXT = '$(x) Formatting disabled'
-export const DISABLE_TEXT = '$(check) Formatting enabled'
+export const ENABLED_TEXT = '$(check) Formatting'
+export const DISABLED_TEXT = '$(x) Formatting'

src/extension.ts

@@ -1,9 +1,6 @@
-import {
-  workspace,
-  window,
-  ExtensionContext
-} from 'vscode'
+import { workspace, window, ExtensionContext } from 'vscode'
 import { get } from 'lodash'
+import getInitialFormattingConfiguration from './helpers/getInitialFormattingConfiguration'
 import initCommand from './helpers/initCommand'
 import initStatusBar from './helpers/initStatusBar'
 
@@ -12,8 +9,15 @@ export function activate(extensionContext: ExtensionContext) {
     'editor',
     get(window, 'activeTextEditor.document.uri')
   )
+  const initialFormattingConfiguration = getInitialFormattingConfiguration(
+    editorConfiguration
+  )
   const statusBar = initStatusBar()
-  const command = initCommand(editorConfiguration, statusBar)
+  const command = initCommand(
+    editorConfiguration,
+    initialFormattingConfiguration,
+    statusBar
+  )
 
   extensionContext.subscriptions.push(statusBar)
   extensionContext.subscriptions.push(command)

src/helpers/getInitialFormattingConfiguration.ts

@@ -0,0 +1,29 @@
+import { WorkspaceConfiguration } from 'vscode'
+import { FORMATTING_SETTINGS } from '../constants'
+
+export type FormattingConfiguration = {
+  [formatOnPaste: string]: boolean
+  formatOnSave: boolean
+  formatOnType: boolean
+}
+
+const getInitialFormattingConfiguration = (
+  editorConfiguration: WorkspaceConfiguration
+): FormattingConfiguration => {
+  const initialFormattingConfiguration: FormattingConfiguration = FORMATTING_SETTINGS.reduce(
+    (configuration, setting) => {
+      const initialSetting = editorConfiguration.get(setting, undefined)
+
+      if (typeof initialSetting !== 'undefined') {
+        configuration[setting] = initialSetting
+      }
+
+      return configuration
+    },
+    {} as FormattingConfiguration
+  )
+
+  return initialFormattingConfiguration
+}
+
+export default getInitialFormattingConfiguration

src/helpers/initCommand.ts

@@ -8,31 +8,46 @@ import {
 import {
   COMMAND_NAME,
   FORMATTING_SETTINGS,
-  ENABLE_TEXT,
-  DISABLE_TEXT
+  ENABLED_TEXT,
+  DISABLED_TEXT
 } from '../constants'
+import { FormattingConfiguration } from './getInitialFormattingConfiguration'
 
 const CONFIGURATION_TARGET = ConfigurationTarget.Global
 const initCommand = (
   editorConfiguration: WorkspaceConfiguration,
+  initialFormattingConfiguration: FormattingConfiguration,
   statusBar: StatusBarItem
-) : Disposable => {
-  let toggle = false
+): Disposable => {
+  let shouldDisable = true
 
   return commands.registerCommand(`extension.${COMMAND_NAME}`, () => {
-    FORMATTING_SETTINGS.forEach(key => {
-      if (!toggle) {
-        editorConfiguration.update(key, undefined, CONFIGURATION_TARGET)
-        statusBar.text = ENABLE_TEXT
+    FORMATTING_SETTINGS.forEach(setting => {
+      const hasInitialValue =
+        typeof initialFormattingConfiguration[setting] !== 'undefined'
+
+      if (shouldDisable) {
+        editorConfiguration.update(
+          setting,
+          // Only set to `false` if it had an initial value, to not mess up the
+          // user’s config. Setting to `undefined` would remove the setting from
+          // the config.
+          hasInitialValue ? false : undefined,
+          CONFIGURATION_TARGET
+        )
 
         return
       }
 
-      editorConfiguration.update(key, true, CONFIGURATION_TARGET)
-      statusBar.text = DISABLE_TEXT
+      // Set the formatting back to the initial configuration, only if it had
+      // an initial value. All formatting settings default to `false`.
+      if (hasInitialValue) {
+        editorConfiguration.update(setting, true, CONFIGURATION_TARGET)
+      }
     })
 
-    toggle = !toggle
+    statusBar.text = shouldDisable ? DISABLED_TEXT : ENABLED_TEXT
+    shouldDisable = !shouldDisable
   })
 }
 

src/helpers/initStatusBar.ts

@@ -1,12 +1,12 @@
 import { window, StatusBarAlignment, StatusBarItem } from 'vscode'
-import { COMMAND_NAME, DISABLE_TEXT } from '../constants'
+import { COMMAND_NAME, ENABLED_TEXT } from '../constants'
 
 const initStatusBar = (): StatusBarItem => {
   // `-1` matches the Prettier extension’s status bar priority.
   const statusBar = window.createStatusBarItem(StatusBarAlignment.Right, -1)
   statusBar.command = `extension.${COMMAND_NAME}`
   statusBar.tooltip = 'Enable/Disable formatting'
-  statusBar.text = DISABLE_TEXT
+  statusBar.text = ENABLED_TEXT
   statusBar.show()
 
   return statusBar