Implement basic support for running in terminal to support reading st…

…din.

Fixes #99.

src/debug/dart_debug_impl.ts

@@ -57,6 +57,7 @@ export class DartDebugSession extends DebugSession {
 	private logStream?: fs.WriteStream;
 	public debugSdkLibraries = false;
 	public debugExternalLibraries = false;
+	public sendOutputAsCustomEvent = false;
 	public showDartDeveloperLogs = true;
 	public useFlutterStructuredErrors = false;
 	public evaluateGettersInDebugViews = false;
@@ -135,6 +136,7 @@ export class DartDebugSession extends DebugSession {
 		this.showDartDeveloperLogs = args.showDartDeveloperLogs;
 		this.useFlutterStructuredErrors = args.useFlutterStructuredErrors;
 		this.evaluateGettersInDebugViews = args.evaluateGettersInDebugViews;
+		this.sendOutputAsCustomEvent = args.console === "terminal";
 		this.debuggerHandlesPathsEverywhereForBreakpoints = args.debuggerHandlesPathsEverywhereForBreakpoints;
 		this.logFile = args.observatoryLogFile;
 		this.maxLogLineLength = args.maxLogLineLength;
@@ -1200,6 +1202,15 @@ export class DartDebugSession extends DebugSession {
 					this.errorResponse(response, e && e.message);
 				}
 				break;
+			case "dart.userInput":
+				if (this.childProcess && !this.childProcess.killed && !this.processExited) {
+					try {
+						this.childProcess.stdin.write(args.input);
+					} catch (e) {
+						this.logger.error(`Failed to write to process stdin: ${e}`);
+					}
+				}
+				break;
 			// Flutter requests that may be sent during test runs or other places
 			// that we don't currently support. TODO: Fix this by moving all the
 			// service extension stuff out of Flutter to here, and making it not
@@ -1801,8 +1812,8 @@ export class DartDebugSession extends DebugSession {
 
 		const lastNewLine = this.logBuffer[category].lastIndexOf("\n");
 		if (lastNewLine !== -1) {
-			const processString = this.logBuffer[category].substr(0, lastNewLine);
-			this.logBuffer[category] = this.logBuffer[category].substr(lastNewLine);
+			const processString = this.logBuffer[category].substr(0, lastNewLine + 1);
+			this.logBuffer[category] = this.logBuffer[category].substr(lastNewLine + 1);
 			this.logToUser(processString, category);
 		}
 	}
@@ -1811,6 +1822,10 @@ export class DartDebugSession extends DebugSession {
 	// Logs a message back to the editor. Does not add its own newlines, you must
 	// provide them!
 	protected logToUser(message: string, category?: string, colorText = (s: string) => s) {
+		if (this.sendOutputAsCustomEvent) {
+			this.sendEvent(new Event("dart.output", { message, category }));
+			return;
+		}
 		// Extract stack frames from the message so we can do nicer formatting of them.
 		const frame = this.getStackFrameData(message) || this.getWebStackFrameData(message) || this.getMessageWithUriData(message);
 

src/extension/commands/debug.ts

@@ -17,7 +17,7 @@ import { FlutterServiceExtensionArgs, FlutterVmServiceExtensions, timeDilationNo
 import { DebuggerType } from "../providers/debug_config_provider";
 import { PubGlobal } from "../pub/global";
 import { DevToolsManager } from "../sdk/dev_tools";
-import { DartDebugSessionInformation } from "../utils/vscode/debug";
+import { DartDebugSessionInformation, DartDebugSessionPseudoterminal } from "../utils/vscode/debug";
 import { envUtils } from "../utils/vscode/editor";
 
 export const debugSessions: DartDebugSessionInformation[] = [];
@@ -249,7 +249,15 @@ export class DebugCommands {
 
 	public handleDebugSessionStart(s: vs.DebugSession): void {
 		if (s.type === "dart") {
-			const session = new DartDebugSessionInformation(s, s.configuration ? DebuggerType[s.configuration.debuggerType] : "<unknown>");
+			const debuggerType = s.configuration ? DebuggerType[s.configuration.debuggerType] : "<unknown>";
+			const consoleType: "debugConsole" | "terminal" = s.configuration.console;
+			let terminal: DartDebugSessionPseudoterminal | undefined;
+			if (consoleType === "terminal") {
+				const terminalName = s.name || debuggerType;
+				terminal = new DartDebugSessionPseudoterminal(terminalName);
+				terminal.userInput((input) => s.customRequest("dart.userInput", { input }));
+			}
+			const session = new DartDebugSessionInformation(s, debuggerType, terminal);
 			// If we're the first fresh debug session, reset all settings to default.
 			// Subsequent launches will inherit the "current" values.
 			if (debugSessions.length === 0)
@@ -305,9 +313,14 @@ export class DebugCommands {
 		debugSessions.splice(sessionIndex, 1);
 
 		this.clearProgressIndicators(session);
+
+		if (session.terminal)
+			session.terminal.end();
+
 		this.debugMetrics.hide();
 		const debugSessionEnd = new Date();
 		this.analytics.logDebugSessionDuration(session.debuggerType, debugSessionEnd.getTime() - session.sessionStart.getTime());
+
 		// If this was the last session terminating, then remove all the flags for which service extensions are supported.
 		// Really we should track these per-session, but the changes of them being different given we only support one
 		// SDK at a time are practically zero.
@@ -383,6 +396,12 @@ export class DebugCommands {
 			);
 		} else if (e.event === "dart.launched") {
 			this.clearProgressIndicators(session);
+		} else if (e.event === "dart.output") {
+			if (session.terminal) {
+				session.terminal.addOutput(e.body.message, e.body.category);
+			} else {
+				this.logger.warn(`Got output event for session without pseudoterminal: ${e.body.message}`);
+			}
 		} else if (e.event === "dart.progress") {
 			if (e.body.message) {
 				if (session.launchProgressReporter) {

src/extension/utils/vscode/debug.ts

@@ -1,5 +1,6 @@
 import * as vs from "vscode";
 import { PromiseCompleter } from "../../../shared/utils";
+import { red, yellow } from "../../../shared/utils/colors";
 
 export class DartDebugSessionInformation {
 	public observatoryUri?: string;
@@ -12,5 +13,68 @@ export class DartDebugSessionInformation {
 	public progressReporter?: vs.Progress<{ message?: string; increment?: number; }>;
 	public progressID?: string;
 	public readonly sessionStart: Date = new Date();
-	constructor(public readonly session: vs.DebugSession, public readonly debuggerType: string) { }
+	constructor(public readonly session: vs.DebugSession, public readonly debuggerType: string, public readonly terminal: DartDebugSessionPseudoterminal | undefined) { }
+}
+
+const spawnedTerminalsByName: { [key: string]: vs.Terminal } = {};
+export class DartDebugSessionPseudoterminal {
+	private readonly userInputEmitter = new vs.EventEmitter<string>();
+	public readonly userInput = this.userInputEmitter.event;
+	private readonly emitter = new vs.EventEmitter<string>();
+	private readonly terminal: vs.Terminal;
+	private readonly pseudoterminal: vs.Pseudoterminal;
+	private isRunning = true;
+
+	constructor(public readonly terminalName: string) {
+		this.pseudoterminal = {
+			close: () => { },  // TODO: End debug session!
+			handleInput: (data) => {
+				if (!this.isRunning)
+					return;
+
+				data = data === "\r" ? "\r\n" : data;
+				this.addOutput(data, "userInput");
+				this.userInputEmitter.fire(data);
+			},
+			onDidWrite: this.emitter.event,
+			// tslint:disable-next-line: no-empty
+			open: () => { },
+
+		};
+		// Close any existing terminal with the same name to ensure we're not creating
+		// new ones each time.
+		if (spawnedTerminalsByName[terminalName])
+			spawnedTerminalsByName[terminalName].dispose();
+		this.terminal = vs.window.createTerminal({ name: terminalName, pty: this.pseudoterminal });
+		spawnedTerminalsByName[terminalName] = this.terminal;
+		this.terminal.show();
+	}
+
+	public end() {
+		// Used to stop echoing user input back once the process has terminated.
+		this.isRunning = false;
+	}
+
+	public addOutput(output: string, category: string) {
+		if (!output)
+			return;
+
+		// If we don't send \r's then VS Code's terminal will not reset
+		// to column 0.
+		output = output.replace(/\n/g, "\r\n");
+
+		switch (category) {
+			case "stderr":
+				output = red(output);
+				break;
+			case "stdout":
+			case "userInput":
+				break;
+			default:
+				output = yellow(output);
+				break;
+		}
+
+		this.emitter.fire(output);
+	}
 }