Adding two unit test to make sure we don’t create sessions for the wrong timestamps

Support/HockeySDKTests/BITMetricsManagerTests.m

@@ -21,12 +21,12 @@
 @implementation BITMetricsManagerTests
 
 - (void)setUp {
-    [super setUp];
-    // Put setup code here. This method is called before the invocation of each test method in the class.
+  [super setUp];
+  // Put setup code here. This method is called before the invocation of each test method in the class.
 }
 
 - (void)tearDown {
-    [super tearDown];
+  [super tearDown];
 }
 
 - (void)testMetricsManagerGetsInstantiated {
@@ -92,9 +92,9 @@
 #pragma clang diagnostic pop
   
   OCMExpect([mockChannel enqueueTelemetryItem:[OCMArg checkWithBlock:^BOOL(NSObject *value)
-                                             {
-                                               return [value isKindOfClass:[BITSessionStateData class]];
-                                             }]]);
+                                               {
+                                                 return [value isKindOfClass:[BITSessionStateData class]];
+                                               }]]);
   [self.sut trackSessionWithState:BITSessionState_start];
   OCMVerifyAll(mockChannel);
 }
@@ -109,7 +109,7 @@
 #pragma clang diagnostic ignored "-Wnonnull"
   self.sut = [[BITMetricsManager alloc] initWithChannel:nil telemetryContext:mockContext persistence:nil userDefaults:testUserDefaults];
 #pragma clang diagnostic pop
-
+  
   NSString *testSessionId = @"sessionId";
   
   OCMExpect([mockContext setSessionId:testSessionId]);
@@ -120,4 +120,87 @@
   OCMVerifyAll(mockContext);
 }
 
+- (void)testNewSessionCreated {
+  NSUserDefaults *testUserDefaults = [NSUserDefaults new];
+  BITTelemetryContext *context = [BITTelemetryContext new];
+  
+  BITChannel *channel = [BITChannel new];
+  id mockChannel = OCMPartialMock(channel);
+  
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnonnull"
+  self.sut = [[BITMetricsManager alloc] initWithChannel:mockChannel telemetryContext:context persistence:nil userDefaults:testUserDefaults];
+#pragma clang diagnostic pop
+
+  int sessionStartCount = 0;
+  int sessionNotRenewedCount = 0;
+  
+  for(int i = 0; i < 100; i++) {
+    double randomOffset = (i%2 == 0) ? arc4random_uniform(1000 - 20 + 1) + 20 : arc4random_uniform(19 - 0 + 1) + 0;
+    double backgroundtime = [[NSDate date] timeIntervalSince1970] - randomOffset;
+    [testUserDefaults setDouble:backgroundtime forKey:@"BITApplicationDidEnterBackgroundTime"];
+    
+    [self.sut startNewSessionIfNeeded];
+    
+    NSLog(@"Test iteration %i", i);
+
+    
+    if(randomOffset >= 20.0) {
+      NSLog(@"Calling OCMVerify for %f", randomOffset);
+      OCMVerify([mockChannel enqueueTelemetryItem:anything()]);
+      sessionStartCount +=1;
+    }
+    else {
+      NSLog(@"Calling OCMReject for %f", randomOffset);
+      // we cant OCMReject for the mockChannel as it will fail because enqueueTelemetryItem has been invoked before for all
+      // randomOffset >= 20.
+      sessionNotRenewedCount +=1;
+    }
+  }
+  
+  // Ac we can't use OCMReject, at least verify the counts of the cases.
+  XCTAssertEqual(sessionStartCount, 50);
+  XCTAssertEqual(sessionNotRenewedCount, 50);
+}
+
+- (void)testNewSessionNeverCreated {
+  NSUserDefaults *testUserDefaults = [NSUserDefaults new];
+  BITTelemetryContext *context = [BITTelemetryContext new];
+  
+  BITChannel *channel = [BITChannel new];
+  id mockChannel = OCMPartialMock(channel);
+  
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnonnull"
+  self.sut = [[BITMetricsManager alloc] initWithChannel:mockChannel telemetryContext:context persistence:nil userDefaults:testUserDefaults];
+#pragma clang diagnostic pop
+  
+  int sessionStartCount = 0;
+  int sessionNotRenewedCount = 0;
+  for(int i = 0; i < 100; i++) {
+    double randomOffset = (i%2 == 0) ? arc4random_uniform(19 - 0 + 1) + 0 : arc4random_uniform(19 - 0 + 1) + 0;
+    double backgroundtime = [[NSDate date] timeIntervalSince1970] - randomOffset;
+    [testUserDefaults setDouble:backgroundtime forKey:@"BITApplicationDidEnterBackgroundTime"];
+    
+    [self.sut startNewSessionIfNeeded];
+    
+    NSLog(@"Test iteration %i", i);
+    
+    if(randomOffset >= 20.0) {
+      NSLog(@"Calling OCMVerify for %f", randomOffset);
+      OCMVerify([mockChannel enqueueTelemetryItem:anything()]);
+      sessionStartCount +=1;
+    }
+    else {
+      NSLog(@"Calling OCMReject for %f", randomOffset);
+      OCMReject([mockChannel enqueueTelemetryItem:anything()]);
+      sessionNotRenewedCount +=1;
+    }
+  }
+  
+  XCTAssertEqual(sessionStartCount, 0);
+  XCTAssertEqual(sessionNotRenewedCount, 100);
+}
+
+
 @end