From a1da7709f8638b08d4c77fba86e3b7422ef0faea Mon Sep 17 00:00:00 2001
From: Vladimir Matveev <vladima@microsoft.com>
Date: Thu, 18 Aug 2016 23:41:48 -0700
Subject: [PATCH] propagate debug/inspect flags to typingsInstaller process

---
 src/server/server.ts | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/src/server/server.ts b/src/server/server.ts
index dc614fba1f7..2f98db89833 100644
--- a/src/server/server.ts
+++ b/src/server/server.ts
@@ -183,9 +183,25 @@ namespace ts.server {
 
             let args: string[] = [];
             if (this.logger.loggingEnabled() && this.logger.getLogFileName()) {
-                args = [ "--logFile", combinePaths(getDirectoryPath(normalizeSlashes(this.logger.getLogFileName())), `ti-${process.pid}.log`) ];
+                args.push("--logFile", combinePaths(getDirectoryPath(normalizeSlashes(this.logger.getLogFileName())), `ti-${process.pid}.log`));
             }
-            this.installer = childProcess.fork(combinePaths(__dirname, "typingsInstaller.js"), args);
+            let execArgv: string[] = [];
+            {
+                for (const arg of process.execArgv) {
+                    const match = /^--(debug|inspect)(=(\d+))?$/.exec(arg);
+                    if (match) {
+                        // if port is specified - use port + 1
+                        // otherwise pick a default port depending on if 'debug' or 'inspect' and use its value + 1 
+                        let currentPort = match[3] !== undefined
+                            ? +match[3]
+                            : match[1] === "debug" ? 5858 : 9229;
+                        execArgv.push(`--${match[1]}=${currentPort + 1}`);
+                        break;
+                    }
+                }
+            }
+            
+            this.installer = childProcess.fork(combinePaths(__dirname, "typingsInstaller.js"), args, { execArgv });
             this.installer.on("message", m => this.handleMessage(m));
             process.on("exit", () => {
                 this.installer.kill();