Method spawnServer

src/extension/analysis/analyzer.ts:553–607

(logger: Logger, sdks: DartSdks)

	}

	private spawnServer(logger: Logger, sdks: DartSdks): Promise<StreamInfo> {
		// TODO: Replace with constructing an Analyzer that passes LSP flag (but still reads config
		// from paths etc) and provide it's process.
		const vmPath = path.join(sdks.dart, dartVMPath);
		const args = getAnalyzerArgs(logger);

		logger.info(`Spawning ${vmPath} with args ${JSON.stringify(args)}`);
		const analysisServerStartTime = Date.now();
		const process = safeToolSpawn(undefined, vmPath, args);
		// Ensure during dispose we terminate the process if it doesn't
		// naturally exit in time.
		this.disposables.push({
			dispose: () => this.handleDisposeCleanup(process)
		});
		logger.info(`    PID: ${process.pid}`);

		const reader = process.stdout.pipe(new LoggingTransform(logger, "<=="));
		const writer = new LoggingTransform(logger, "==>");
		writer.pipe(process.stdin);

		process.stderr.on("data", (data) => {
			const errorOutput = data.toString();

			// Handle some well-known kinds of errors to help troubleshoot.
			if (typeof errorOutput === "string") {
				if (!hasShownAnalysisServerVersionMismatchError && config.analyzerPath && errorOutput.includes("analysis_server.dart") && errorOutput.includes("The specified language version is too high")) {
					hasShownAnalysisServerVersionMismatchError = true;
					void promptToReloadExtension(logger, {
						prompt: "Running the analysis server from source failed because of a version mismatch. Is your Dart SDK an older version than this server version requires?",
						offerLog: true,
						severity: "ERROR",
						restartReason: ExtensionRestartReason.AnalysisServerFromSourceMismatch
					});
				}
			}

			logger.error(errorOutput);
		});

		const processName = "Analysis server";
		process.on("close", (code, signal) => logger.info(`${processName} closed (${code}, ${signal})`));
		process.on("exit", (code, signal) => {
			logger.info(`${processName} exited (${code}, ${signal})`);

			if (code)
				reportAnalyzerTerminatedWithError(logger);

			if (!config.analyzerPath) { // Don't report for devs running from source.
				const durationMs = Date.now() - analysisServerStartTime;
				this.analytics.logAnalysisServerTerminate(code ?? 0, durationMs);
			}
		});

		return Promise.resolve({ reader, writer });
	}

	/**
	 * Handle a call to dispose by waiting for the process to exit, or