Code improvements.

extension/src/debugger/EnhancedDebugSession.ts

@@ -0,0 +1,70 @@
+import { DebugSession } from "vscode";
+import { CompletionItem } from "../webviewContract";
+import { observable } from "mobx";
+
+export class EnhancedDebugSession {
+	@observable protected activeStackFrame: number | undefined;
+
+	constructor(public readonly session: DebugSession) {}
+
+	protected async getStackTrace(args: {
+		threadId: number;
+		startFrame?: number;
+		levels?: number;
+	}): Promise<{ totalFrames?: number; stackFrames: StackFrame[] }> {
+		try {
+			const reply = (await this.session.customRequest("stackTrace", {
+				threadId: args.threadId,
+				levels: args.levels,
+				startFrame: args.startFrame || 0,
+			})) as { totalFrames?: number; stackFrames: StackFrame[] };
+			return reply;
+		} catch (e) {
+			console.error(e);
+			throw e;
+		}
+	}
+
+	public async getCompletions(args: {
+		text: string;
+		column: number;
+		frameId: number | undefined;
+	}): Promise<CompletionItem[]> {
+		try {
+			const reply = await this.session.customRequest("completions", {
+				text: args.text,
+				frameId: args.frameId,
+				column: args.column,
+			});
+			if (!reply) {
+				return [];
+			}
+			return reply.targets;
+		} catch (error) {
+			console.error(error);
+			return [];
+		}
+	}
+
+	/**
+	 * Evaluates the given expression.
+	 * If context is "watch", long results are usually shortened.
+	 */
+
+	public async evaluate(args: {
+		expression: string;
+		frameId: number | undefined;
+		context: "watch" | "repl" | "copy";
+	}): Promise<{ result: string }> {
+		const reply = await this.session.customRequest("evaluate", {
+			expression: args.expression,
+			frameId: args.frameId,
+			context: args.context,
+		});
+		return { result: reply.result };
+	}
+}
+interface StackFrame {
+	id: number;
+	name: string;
+}