refactor: use optional chaining (#448)

Author: noritaka1166

src/DocumentWatcher.ts

@@ -145,7 +145,7 @@ export default class DocumentWatcher {
 	}
 
 	private async handleTextEditorChange(editor?: TextEditor) {
-		if (editor && editor.document) {
+		if (editor?.document) {
 			const newOptions = await resolveTextEditorOptions(
 				(this.doc = editor.document),
 				{

src/commands/generateEditorConfig.ts

@@ -11,8 +11,7 @@ const readFile = promisify(_readFile)
  * current vscode settings.
  */
 export async function generateEditorConfig(uri: Uri) {
-	const workspaceUri =
-		workspace.workspaceFolders && workspace.workspaceFolders[0].uri
+	const workspaceUri = workspace.workspaceFolders?.[0].uri
 	const currentUri = uri || workspaceUri
 	if (!currentUri) {
 		window.showErrorMessage("Workspace doesn't contain any folders.")

src/transformations/InsertFinalNewline.ts

@@ -30,7 +30,7 @@ export class InsertFinalNewline extends PreSaveTransformation {
 			return { edits: [] }
 		}
 
-		if (window.activeTextEditor && window.activeTextEditor.document === doc) {
+		if (window.activeTextEditor?.document === doc) {
 			commands.executeCommand('editor.action.insertFinalNewLine')
 			return {
 				edits: [],

src/transformations/TrimTrailingWhitespace.ts

@@ -40,7 +40,7 @@ export class TrimTrailingWhitespace extends PreSaveTransformation {
 			return { edits: [] }
 		}
 
-		if (window.activeTextEditor && window.activeTextEditor.document === doc) {
+		if (window.activeTextEditor?.document === doc) {
 			const trimReason =
 				reason !== TextDocumentSaveReason.Manual ? 'auto-save' : null
 			commands.executeCommand('editor.action.trimTrailingWhitespace', {