Fix #438 When debug process is stopped kill all processes started by it(

#765)

* Attempt to fix #438

* Fix linting issues

scripts/terminateProcess.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+terminateTree() {
+	for cpid in $(/usr/bin/pgrep -P $1); do
+		terminateTree $cpid
+	done
+	kill -9 $1 > /dev/null 2>&1
+}
+
+for pid in $*; do
+	terminateTree $pid
+done

src/debugAdapter/goDebug.ts

@@ -9,7 +9,7 @@ import { DebugProtocol } from 'vscode-debugprotocol';
 import { DebugSession, InitializedEvent, TerminatedEvent, ThreadEvent, StoppedEvent, OutputEvent, Thread, StackFrame, Scope, Source, Handles } from 'vscode-debugadapter';
 import { readFileSync, existsSync, lstatSync } from 'fs';
 import { basename, dirname } from 'path';
-import { spawn, ChildProcess } from 'child_process';
+import { spawn, ChildProcess, execSync, spawnSync } from 'child_process';
 import { Client, RPCConnection } from 'json-rpc2';
 import { getBinPathWithPreferredGopath } from '../goPath';
 import * as logger from 'vscode-debug-logger';
@@ -307,7 +307,7 @@ class Delve {
 				});
 			});
 		} else {
-			this.debugProcess.kill();
+			killTree(this.debugProcess.pid);
 		}
 	}
 }
@@ -759,4 +759,24 @@ function random(low: number, high: number): number {
 	return Math.floor(Math.random() * (high - low) + low);
 }
 
+function killTree(processId: number): void {
+	if (process.platform === 'win32') {
+		const TASK_KILL = 'C:\\Windows\\System32\\taskkill.exe';
+
+		// when killing a process in Windows its child processes are *not* killed but become root processes.
+		// Therefore we use TASKKILL.EXE
+		try {
+			execSync(`${TASK_KILL} /F /T /PID ${processId}`);
+		} catch (err) {
+		}
+	} else {
+		// on linux and OS X we kill all direct and indirect child processes as well
+		try {
+			const cmd = path.join(__dirname, '../../../scripts/terminateProcess.sh');
+			spawnSync(cmd, [ processId.toString() ]);
+		} catch (err) {
+		}
+	}
+}
+
 DebugSession.run(GoDebugSession);