From e41fb7185da2fef25f1a64a36d856c7c14bb28c8 Mon Sep 17 00:00:00 2001
From: Fredy Wijaya <fredyw@google.com>
Date: Mon, 9 Sep 2024 12:44:31 -0500
Subject: [PATCH] mobile: Fix missing logging output in Swift integration tests
 (#36040)

In Swift, `print` goes to stdout buffering. The fix is to flush the
`stdout` and `stderr` before the end of the test.

See
https://github.com/swiftlang/swift-corelibs-xctest/issues/422#issuecomment-1310952437

Risk Level: low (tests only)
Testing: CI
Docs Changes: n/a
Release Notes: n/a
Platform Specific Features: n/a

---------

Signed-off-by: Fredy Wijaya <fredyw@google.com>
---
 .../swift/integration/CancelGRPCStreamTest.swift  |  7 +++++++
 .../test/swift/integration/CancelStreamTest.swift |  7 +++++++
 .../integration/EndToEndNetworkingTest.swift      |  7 +++++++
 mobile/test/swift/integration/EngineApiTest.swift |  7 +++++++
 .../swift/integration/FilterResetIdleTest.swift   |  7 +++++++
 .../swift/integration/GRPCReceiveErrorTest.swift  |  7 +++++++
 .../test/swift/integration/IdleTimeoutTest.swift  |  7 +++++++
 .../swift/integration/KeyValueStoreTest.swift     |  7 +++++++
 .../test/swift/integration/ReceiveDataTest.swift  |  7 +++++++
 .../test/swift/integration/ReceiveErrorTest.swift | 10 +++++++---
 .../integration/ResetConnectivityStateTest.swift  |  7 +++++++
 mobile/test/swift/integration/SendDataTest.swift  |  7 +++++++
 .../test/swift/integration/SendHeadersTest.swift  |  7 +++++++
 .../test/swift/integration/SendTrailersTest.swift |  7 +++++++
 .../swift/integration/SetEventTrackerTest.swift   |  7 +++++++
 .../SetEventTrackerTestNoTracker.swift            |  7 +++++++
 mobile/test/swift/integration/SetLoggerTest.swift | 15 ++++++++++-----
 .../proxying/HTTPRequestUsingProxyTest.swift      |  7 +++++++
 18 files changed, 129 insertions(+), 8 deletions(-)

diff --git a/mobile/test/swift/integration/CancelGRPCStreamTest.swift b/mobile/test/swift/integration/CancelGRPCStreamTest.swift
index b878490af6ff..6b35c002f08c 100644
--- a/mobile/test/swift/integration/CancelGRPCStreamTest.swift
+++ b/mobile/test/swift/integration/CancelGRPCStreamTest.swift
@@ -11,6 +11,13 @@ final class CancelGRPCStreamTests: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testCancelGRPCStream() {
     let filterName = "cancel_validation_filter"
 
diff --git a/mobile/test/swift/integration/CancelStreamTest.swift b/mobile/test/swift/integration/CancelStreamTest.swift
index e6dd2dec4e16..a53f165b2c4b 100644
--- a/mobile/test/swift/integration/CancelStreamTest.swift
+++ b/mobile/test/swift/integration/CancelStreamTest.swift
@@ -11,6 +11,13 @@ final class CancelStreamTests: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testCancelStream() {
     let filterName = "cancel_validation_filter"
 
diff --git a/mobile/test/swift/integration/EndToEndNetworkingTest.swift b/mobile/test/swift/integration/EndToEndNetworkingTest.swift
index 18c1e5684e62..638eefc62333 100644
--- a/mobile/test/swift/integration/EndToEndNetworkingTest.swift
+++ b/mobile/test/swift/integration/EndToEndNetworkingTest.swift
@@ -10,6 +10,13 @@ final class EndToEndNetworkingTest: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testNetworkRequestReturnsHeadersAndData() {
     EnvoyTestServer.startHttp1PlaintextServer()
     EnvoyTestServer.setHeadersAndData(
diff --git a/mobile/test/swift/integration/EngineApiTest.swift b/mobile/test/swift/integration/EngineApiTest.swift
index 669269526817..22c8a5b68868 100644
--- a/mobile/test/swift/integration/EngineApiTest.swift
+++ b/mobile/test/swift/integration/EngineApiTest.swift
@@ -9,6 +9,13 @@ final class EngineApiTest: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testEngineApis() throws {
     let engineExpectation = self.expectation(description: "Engine Running")
 
diff --git a/mobile/test/swift/integration/FilterResetIdleTest.swift b/mobile/test/swift/integration/FilterResetIdleTest.swift
index b9ed4755ba9f..da7f5a528829 100644
--- a/mobile/test/swift/integration/FilterResetIdleTest.swift
+++ b/mobile/test/swift/integration/FilterResetIdleTest.swift
@@ -11,6 +11,13 @@ final class FilterResetIdleTests: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testFilterResetIdle() {
     let filterName = "reset_idle_test_filter"
 
diff --git a/mobile/test/swift/integration/GRPCReceiveErrorTest.swift b/mobile/test/swift/integration/GRPCReceiveErrorTest.swift
index 6713b185eb8b..a1266db281c7 100644
--- a/mobile/test/swift/integration/GRPCReceiveErrorTest.swift
+++ b/mobile/test/swift/integration/GRPCReceiveErrorTest.swift
@@ -11,6 +11,13 @@ final class GRPCReceiveErrorTests: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testReceiveError() {
     let filterName = "error_validation_filter"
 
diff --git a/mobile/test/swift/integration/IdleTimeoutTest.swift b/mobile/test/swift/integration/IdleTimeoutTest.swift
index 4f3d18440f28..95324f9195cd 100644
--- a/mobile/test/swift/integration/IdleTimeoutTest.swift
+++ b/mobile/test/swift/integration/IdleTimeoutTest.swift
@@ -11,6 +11,13 @@ final class IdleTimeoutTests: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testIdleTimeout() {
     let filterName = "reset_idle_test_filter"
 
diff --git a/mobile/test/swift/integration/KeyValueStoreTest.swift b/mobile/test/swift/integration/KeyValueStoreTest.swift
index b33204b2c52b..595bae134513 100644
--- a/mobile/test/swift/integration/KeyValueStoreTest.swift
+++ b/mobile/test/swift/integration/KeyValueStoreTest.swift
@@ -11,6 +11,13 @@ final class KeyValueStoreTests: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testKeyValueStore() {
     // swiftlint:disable:next line_length
     let kvStoreType = "type.googleapis.com/envoymobile.extensions.filters.http.test_kv_store.TestKeyValueStore"
diff --git a/mobile/test/swift/integration/ReceiveDataTest.swift b/mobile/test/swift/integration/ReceiveDataTest.swift
index 2e2855535508..483c947e7261 100644
--- a/mobile/test/swift/integration/ReceiveDataTest.swift
+++ b/mobile/test/swift/integration/ReceiveDataTest.swift
@@ -11,6 +11,13 @@ final class ReceiveDataTests: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testReceiveData() {
     let directResponseBody = "response_body"
     EnvoyTestServer.startHttp1PlaintextServer()
diff --git a/mobile/test/swift/integration/ReceiveErrorTest.swift b/mobile/test/swift/integration/ReceiveErrorTest.swift
index 24d9a2b0b194..cb8b408adcc6 100644
--- a/mobile/test/swift/integration/ReceiveErrorTest.swift
+++ b/mobile/test/swift/integration/ReceiveErrorTest.swift
@@ -10,6 +10,13 @@ final class ReceiveErrorTests: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testReceiveError() {
     let filterName = "error_validation_filter"
 
@@ -59,9 +66,6 @@ final class ReceiveErrorTests: XCTestCase {
       .setLogger { _, msg in
         print(msg, terminator: "")
       }
-      .setLogger { _, msg in
-          print(msg, terminator: "")
-      }
       .addPlatformFilter(
         name: filterName,
         factory: {
diff --git a/mobile/test/swift/integration/ResetConnectivityStateTest.swift b/mobile/test/swift/integration/ResetConnectivityStateTest.swift
index e0c260feb690..ddeb5bb0590e 100644
--- a/mobile/test/swift/integration/ResetConnectivityStateTest.swift
+++ b/mobile/test/swift/integration/ResetConnectivityStateTest.swift
@@ -11,6 +11,13 @@ final class ResetConnectivityStateTest: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testResetConnectivityState() {
     EnvoyTestServer.startHttp1PlaintextServer()
 
diff --git a/mobile/test/swift/integration/SendDataTest.swift b/mobile/test/swift/integration/SendDataTest.swift
index 25c096e61a94..4a7b736b6f1a 100644
--- a/mobile/test/swift/integration/SendDataTest.swift
+++ b/mobile/test/swift/integration/SendDataTest.swift
@@ -11,6 +11,13 @@ final class SendDataTests: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testSendData() throws {
     EnvoyTestServer.startHttp1PlaintextServer()
     EnvoyTestServer.setHeadersAndData("x-response-foo", header_value: "aaa", response_body: "data")
diff --git a/mobile/test/swift/integration/SendHeadersTest.swift b/mobile/test/swift/integration/SendHeadersTest.swift
index 6b5bc67fce73..46de840b92ef 100644
--- a/mobile/test/swift/integration/SendHeadersTest.swift
+++ b/mobile/test/swift/integration/SendHeadersTest.swift
@@ -11,6 +11,13 @@ final class SendHeadersTests: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testSendHeaders() {
     EnvoyTestServer.startHttp1PlaintextServer()
 
diff --git a/mobile/test/swift/integration/SendTrailersTest.swift b/mobile/test/swift/integration/SendTrailersTest.swift
index e557756c0edb..5f1caa7a2404 100644
--- a/mobile/test/swift/integration/SendTrailersTest.swift
+++ b/mobile/test/swift/integration/SendTrailersTest.swift
@@ -11,6 +11,13 @@ final class SendTrailersTests: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testSendTrailers() throws {
     // swiftlint:disable:next line_length
     let assertionFilterType = "type.googleapis.com/envoymobile.extensions.filters.http.assertion.Assertion"
diff --git a/mobile/test/swift/integration/SetEventTrackerTest.swift b/mobile/test/swift/integration/SetEventTrackerTest.swift
index a13e0ddfed56..beec655a1717 100644
--- a/mobile/test/swift/integration/SetEventTrackerTest.swift
+++ b/mobile/test/swift/integration/SetEventTrackerTest.swift
@@ -11,6 +11,13 @@ final class SetEventTrackerTest: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testSetEventTracker() throws {
     EnvoyTestServer.startHttp1PlaintextServer()
 
diff --git a/mobile/test/swift/integration/SetEventTrackerTestNoTracker.swift b/mobile/test/swift/integration/SetEventTrackerTestNoTracker.swift
index 78449f41f1e0..33f5035191e0 100644
--- a/mobile/test/swift/integration/SetEventTrackerTestNoTracker.swift
+++ b/mobile/test/swift/integration/SetEventTrackerTestNoTracker.swift
@@ -11,6 +11,13 @@ final class SetEventTrackerTestNoTracker: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testEmitEventWithoutSettingEventTracker() throws {
     EnvoyTestServer.startHttp1PlaintextServer()
 
diff --git a/mobile/test/swift/integration/SetLoggerTest.swift b/mobile/test/swift/integration/SetLoggerTest.swift
index afe3a8a1654c..96836ebf9dd0 100644
--- a/mobile/test/swift/integration/SetLoggerTest.swift
+++ b/mobile/test/swift/integration/SetLoggerTest.swift
@@ -11,6 +11,13 @@ final class LoggerTests: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   func testSetLogger() throws {
     let engineExpectation = self.expectation(description: "Run started engine")
     let loggingExpectation = self.expectation(description: "Run used platform logger")
@@ -24,16 +31,14 @@ final class LoggerTests: XCTestCase {
       .setLogLevel(.debug)
       .setLogger { _, msg in
         print(msg, terminator: "")
+        if msg.contains("starting main dispatch loop") {
+          loggingExpectation.fulfill()
+        }
       }
       .addNativeFilter(
         name: "test_logger",
         // swiftlint:disable:next line_length
         typedConfig: "[type.googleapis.com/envoymobile.extensions.filters.http.test_logger.TestLogger]{}")
-      .setLogger { _, msg in
-        if msg.contains("starting main dispatch loop") {
-          loggingExpectation.fulfill()
-        }
-      }
       .setOnEngineRunning {
         engineExpectation.fulfill()
       }
diff --git a/mobile/test/swift/integration/proxying/HTTPRequestUsingProxyTest.swift b/mobile/test/swift/integration/proxying/HTTPRequestUsingProxyTest.swift
index da80194d2ff3..67f3e215bb3f 100644
--- a/mobile/test/swift/integration/proxying/HTTPRequestUsingProxyTest.swift
+++ b/mobile/test/swift/integration/proxying/HTTPRequestUsingProxyTest.swift
@@ -12,6 +12,13 @@ final class HTTPRequestUsingProxyTest: XCTestCase {
     register_test_extensions()
   }
 
+  override static func tearDown() {
+    super.tearDown()
+    // Flush the stdout and stderror to show the print output.
+    fflush(stdout)
+    fflush(stderr)
+  }
+
   private func executeRequest(engine: Engine, scheme: String, authority: String) -> String? {
     let responseHeadersExpectation =
         self.expectation(description: "Successful response headers received")