Merge pull request microsoft#128624 from microsoft/hediet/fix-128302-recovery2

Don't modify ghost text when reading it

Author: hediet

src/vs/editor/contrib/inlineCompletions/ghostText.ts

@@ -18,7 +18,7 @@ export class GhostText {
 }
 
 export interface GhostTextPart {
-	readonly lines: string[];
+	readonly lines: readonly string[];
 	readonly column: number;
 }
 

src/vs/editor/contrib/inlineCompletions/ghostTextWidget.ts

@@ -86,15 +86,15 @@ export class GhostTextWidget extends Disposable {
 		const inlineTexts = new Array<InsertedInlineText>();
 		const additionalLines = new Array<LineData>();
 
-		function addToAdditionalLines(lines: string[], className: string | undefined) {
+		function addToAdditionalLines(lines: readonly string[], className: string | undefined) {
 			if (additionalLines.length > 0) {
 				const lastLine = additionalLines[additionalLines.length - 1];
 				if (className) {
 					lastLine.decorations.push(new LineDecoration(lastLine.content.length + 1, lastLine.content.length + 1 + lines[0].length, className, InlineDecorationType.Regular));
 				}
 				lastLine.content += lines[0];
 
-				lines.splice(0, 1);
+				lines = lines.slice(1);
 			}
 			for (const line of lines) {
 				additionalLines.push({