Call session _onClose only once

Author: oskarhane

src/v1/session.js

@@ -87,7 +87,15 @@ class Session {
    * @return
    */
   close(cb=(()=>null)) {
-    this._onClose(cb);
+    if(this._onClose) {
+      try {
+        this._onClose(cb);
+      } finally {
+        this._onClose = null;
+      }
+    } else {
+      cb();
+    }
   }
 }
 

test/v1/session.test.js

@@ -19,6 +19,7 @@
 
 var neo4j = require("../../lib/v1");
 var StatementType = require("../../lib/v1/result-summary").statementType;
+var Session = require("../../lib/v1/session");
 
 describe('session', function() {
 
@@ -35,6 +36,18 @@ describe('session', function() {
     driver.close();
   });
 
+  it('close should be idempotent ', function(){
+    // Given
+    var counter = 0;
+    var _session = new Session(null, function(){
+      counter++;
+    });
+    _session.close();
+    expect(counter).toBe(1);
+    _session.close();
+    expect(counter).toBe(1);
+  })
+
   it('should expose basic run/subscribe ', function(done) {
     // Given