ruby support

extension/README.md

@@ -25,6 +25,7 @@ See [demos](../demos/) for demos. These languages and debuggers are verified to
 -   C++ using `cppdbg` debug adapter: [✅ Basic Support](../demos/cpp)
 -   Swift using `lldb` debug adapter: [✅ Basic Support](../demos/swift)
 -   Rust using `lldb` debug adapter: [✅ Basic Support](../demos/rust)
+-   Ruby using `rdbg` debug adapter: [✅ Basic Support]
 
 All other languages and debuggers might work too.
 For languages with _Basic Support_, only JSON strings can be visualized - you must implement some logic that builds this JSON for your data structure!

extension/src/VisualizationBackend/RbVisualizationSupport.ts

@@ -0,0 +1,142 @@
+import { DataExtractionResult, DataResult } from "@hediet/debug-visualizer-data-extraction";
+import { hotClass, registerUpdateReconciler } from "@hediet/node-reload";
+import { Config } from "../Config";
+import { DebuggerViewProxy } from "../proxies/DebuggerViewProxy";
+import { DebugSessionProxy } from "../proxies/DebugSessionProxy";
+import { FormattedMessage } from "../webviewContract";
+import { DebugSessionVisualizationSupport, GetVisualizationDataArgs, VisualizationBackend, VisualizationBackendBase } from "./VisualizationBackend";
+
+registerUpdateReconciler(module);
+
+@hotClass(module)
+export class RbEvaluationEngine implements DebugSessionVisualizationSupport {
+	constructor(
+		private readonly debuggerView: DebuggerViewProxy,
+		private readonly config: Config
+	) { }
+
+	createBackend(
+		session: DebugSessionProxy
+	): VisualizationBackend | undefined {
+		const supportedDebugAdapters = ['rdbg'];
+
+		if (supportedDebugAdapters.indexOf(session.session.type) !== -1) {
+			return new RbVisualizationBackend(
+				session,
+				this.debuggerView,
+				this.config
+			);
+		}
+		return undefined;
+	}
+}
+
+class RbVisualizationBackend extends VisualizationBackendBase {
+	public readonly expressionLanguageId = 'ruby';
+	constructor(
+		debugSession: DebugSessionProxy,
+		debuggerView: DebuggerViewProxy,
+		private readonly config: Config
+	) {
+		super(debugSession, debuggerView)
+	}
+
+	private readonly defaultContext = "repl";
+
+	public async getVisualizationData(
+		args: GetVisualizationDataArgs
+	): Promise<
+		| { kind: "data"; result: DataExtractionResult; }
+		| { kind: "error"; message: FormattedMessage; }
+	> {
+		const result = await this._getVisualizationData(args);
+		return result;
+	}
+
+	private async _getVisualizationData({
+		expression,
+		preferredExtractorId
+	}: GetVisualizationDataArgs): Promise<
+		| { kind: "data"; result: DataExtractionResult }
+		| { kind: "error"; message: FormattedMessage }
+	> {
+		try {
+			if (expression.length === 0) throw new Error("No extractors");
+
+			const frameId = this.debuggerView.getActiveStackFrameId(
+				this.debugSession
+			);
+			const initialReply = await this.debugSession.evaluate({
+				expression: "require 'debugvisualizer'",
+				frameId,
+				context: this.defaultContext
+			});
+			if (initialReply.result.includes('LoadError')) {
+				return {
+					kind: "error",
+					message: {
+						kind: "list",
+						items: [
+							"LoadError: Failed to load debugvisualizer.",
+							{
+								kind: "inlineList",
+								items: [
+									"Install the gem by executing:",
+									{ kind: "code", content: "$ bundle add debugvisualizer" },
+								],
+							},
+							{
+								kind: "inlineList",
+								items: [
+									"If bundler is not being used, install the gem by executing:",
+									{ kind: "code", content: "$ gem install debugvisualizer" },
+								],
+							}
+						],
+					}
+				};
+			}
+			const preferredId = preferredExtractorId || '';
+			const wrappedExpr = `
+				DebugVisualizer.to_debug_visualizer_protocol_json("${preferredId}", ${expression})
+			`;
+			const reply = await this.debugSession.evaluate({
+				expression: wrappedExpr,
+				frameId,
+				context: this.defaultContext
+			})
+
+			let dataResult: DataResult;
+			try {
+				// Debuggee converts result to a JSON string twice.
+				dataResult = JSON.parse(JSON.parse(reply.result)) as DataResult;
+			} catch (error) {
+				let message = error.message
+				// The `reply.result` is as follows when error occurs in the evaluation of an expression and parsing will fail.
+				// e.g. "#<ZeroDivisionError: divided by 0>"
+				// In this case, it is more beneficial to display this error message.
+				if (reply.result.includes('Error')) message = reply.result;
+				throw new Error(message)
+			}
+
+			switch (dataResult.kind) {
+				case 'NoExtractors':
+					throw new Error("No extractors");
+				case 'Error':
+					throw new Error(dataResult.message);
+				case 'Data':
+					return {
+						kind: "data",
+						result: dataResult.extractionResult,
+					};
+				default:
+					throw new Error("Invalid Data");
+			}
+		} catch (error) {
+			return {
+				kind: "error",
+				message: error.message
+			};
+		}
+	}
+}

extension/src/VisualizationBackend/index.ts

@@ -3,5 +3,6 @@ export * from "./VisualizationBackend";
 export { ComposedVisualizationSupport } from "./ComposedVisualizationSupport";
 export { JsEvaluationEngine } from "./JsVisualizationSupport";
 export { PyEvaluationEngine } from "./PyVisualizationSupport";
+export { RbEvaluationEngine } from './RbVisualizationSupport';
 export { GenericVisualizationSupport } from "./GenericVisualizationSupport";
 export { ConfigurableVisualizationSupport } from "./ConfigurableVisualizationSupport";

extension/src/extension.ts

@@ -22,6 +22,7 @@ import {
 	ComposedVisualizationSupport,
 	JsEvaluationEngine,
 	PyEvaluationEngine,
+	RbEvaluationEngine,
 	GenericVisualizationSupport,
 	ConfigurableVisualizationSupport,
 } from "./VisualizationBackend";
@@ -53,6 +54,7 @@ export class Extension {
 				),
 				new JsEvaluationEngine(this.debuggerView, this.config),
 				new PyEvaluationEngine(this.debuggerView, this.config),
+				new RbEvaluationEngine(this.debuggerView, this.config),
 				new GenericVisualizationSupport(this.debuggerView),
 			]),
 			this.debuggerView
@@ -102,7 +104,7 @@ export class Extension {
 							if (
 								match.index <= selection.start.character &&
 								selection.start.character <=
-									match.index + match[0].length
+								match.index + match[0].length
 							) {
 								selectedText = match[1];
 							}