From d3025a9270b214b185af79fde1085e0231a8b682 Mon Sep 17 00:00:00 2001
From: Andrey Sokolov <andrey.sokolov@amplitude.com>
Date: Thu, 27 Apr 2023 19:04:50 +0400
Subject: [PATCH] fix: do not overwrite flushIntervalMillis=0 with default
 value (10 seconds)

---
 packages/analytics-core/src/config.ts       |  2 +-
 packages/analytics-core/test/config.test.ts | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/packages/analytics-core/src/config.ts b/packages/analytics-core/src/config.ts
index b882cd7e5..e2a3e86d0 100644
--- a/packages/analytics-core/src/config.ts
+++ b/packages/analytics-core/src/config.ts
@@ -58,7 +58,7 @@ export class Config implements IConfig {
   constructor(options: Options) {
     const defaultConfig = getDefaultConfig();
     this.apiKey = options.apiKey;
-    this.flushIntervalMillis = options.flushIntervalMillis || defaultConfig.flushIntervalMillis;
+    this.flushIntervalMillis = options.flushIntervalMillis ?? defaultConfig.flushIntervalMillis;
     this.flushMaxRetries = options.flushMaxRetries || defaultConfig.flushMaxRetries;
     this.flushQueueSize = options.flushQueueSize || defaultConfig.flushQueueSize;
     this.loggerProvider = options.loggerProvider || defaultConfig.loggerProvider;
diff --git a/packages/analytics-core/test/config.test.ts b/packages/analytics-core/test/config.test.ts
index 3e2563968..8becab36f 100644
--- a/packages/analytics-core/test/config.test.ts
+++ b/packages/analytics-core/test/config.test.ts
@@ -109,4 +109,15 @@ describe('config', () => {
       });
     });
   });
+
+  test('should not overwrite flushIntervalMillis=0 with default value', () => {
+    const defaultConfig = useDefaultConfig();
+    const config = new Config({
+      apiKey: API_KEY,
+      storageProvider: defaultConfig.storageProvider,
+      transportProvider: defaultConfig.transportProvider,
+      flushIntervalMillis: 0,
+    });
+    expect(config.flushIntervalMillis).toEqual(0);
+  });
 });