Reject promise on failure of spawn process (sclang/scsynth)

src/lang/__tests__/sclang-test.js

@@ -165,7 +165,9 @@ describe('sclang', function() {
     // mock spawn to return an event emitter
     it('should spawnProcess', function() {
       var sclang = new SCLang();
-      spyOn(sclang, '_spawnProcess');
+      spyOn(sclang, '_spawnProcess').and.returnValue({
+        pid: 1
+      });
       spyOn(sclang, 'installListeners');
       var promise = sclang.spawnProcess('/tmp/fake/path', {});
       expect(promise).toBeTruthy();

src/lang/sclang.js

@@ -157,7 +157,11 @@ export class SCLang extends EventEmitter {
   spawnProcess(execPath, commandLineOptions) {
     return new Promise((resolve, reject) => {
       var done = false;
+
       this.process = this._spawnProcess(execPath, this.args(commandLineOptions));
+      if (!this.process.pid) {
+        reject(new Error(`Failed to spawn process ${execPath}`));
+      }
 
       var bootListener = (state) => {
         if (state === STATES.READY) {

src/server/server.js

@@ -177,7 +177,11 @@ export class Server extends EventEmitter {
     return new Promise((resolve, reject) => {
       this.isRunning = false;
 
-      this._spawnProcess();
+      try {
+        this._spawnProcess();
+      } catch (e) {
+        reject(e);
+      }
 
       this._serverObservers.stdout = Observable.fromEvent(this.process.stdout, 'data', (data) => String(data));
       this._serverObservers.stdout.subscribe((e) => this.stdout.onNext(e));
@@ -223,6 +227,13 @@ export class Server extends EventEmitter {
         detached: false
       }
     });
+
+    if (!this.process.pid) {
+      let error = `Failed to boot ${execPath}`;
+      this.processEvents.onError(error);
+      throw new Error(error);
+    }
+
     this.processEvents.onNext('pid: ' + this.process.pid);
 
     // when this parent process dies, kill child process