Update tests

Author: 3dgiordano

src/test/java/com/blazemeter/jmeter/http2/integration/HTTP3HappyEyeballsIntegrationTest.java

@@ -155,10 +155,12 @@ public void shouldPreferHttp3WhenRecentSuccessKeepsBaseDelay() throws Exception
       HTTP2JettyClient client = new HTTP2JettyClient(false, "IT-HTTP3-HE-Recent");
       try {
         client.start();
-        // Phase A: establish Alt-Svc and force one confirmed H3 success first.
+        // Phase A: establish Alt-Svc and force one confirmed H3 success first. No protocol is
+        // asserted on this first sample: first contact with an unknown origin explores HTTP/3, so
+        // either side of the race may win it. The warmup loop below is what guarantees the
+        // confirmed HTTP/3 success this test needs.
         HTTPSampleResult first = sample(client, sampler, url);
         assertThat(first.isSuccessful()).isTrue();
-        assertThat(first.getResponseHeaders()).startsWith("HTTP/2");
 
         h2DelayMs.set(500L);
         h3DelayMs.set(0L);
@@ -251,16 +253,42 @@ public void shouldSkipHttp3WhenMarkedBroken() throws Exception {
       HTTP2JettyClient client = new HTTP2JettyClient(false, "IT-HTTP3-HE-Broken");
       try {
         client.start();
-        HTTPSampleResult first = sample(client, sampler, url);
-        assertThat(first.isSuccessful()).isTrue();
-        assertThat(first.getResponseHeaders()).startsWith("HTTP/2");
+        // Setup, in two steps, so that the cooldown ends up being the only thing that can stop
+        // HTTP/3 - otherwise this test passes without the cooldown doing any work.
+        //
+        // First, let HTTP/2 win a race so its Alt-Svc is recorded with h3=true. Marking an origin
+        // broken when nothing is cached for it creates an entry saying h3=false, and that alone
+        // stops HTTP/3 regardless of any cooldown.
+        h3DelayMs.set(1000L);
+        HTTPSampleResult altSvcLearn = sample(client, sampler, url);
+        assertThat(altSvcLearn.isSuccessful()).isTrue();
+        assertThat(altSvcLearn.getResponseHeaders())
+            .as("HTTP/2 has to answer this one for its Alt-Svc to be cached")
+            .startsWith("HTTP/2");
+        h3DelayMs.set(0L);
+
+        // Second, confirm HTTP/3 is actually being attempted now, so that its absence later means
+        // something. No protocol is asserted on these samples: either side of the race may win.
+        boolean http3Attempted = false;
+        for (int attempt = 0; attempt < 6 && !http3Attempted; attempt++) {
+          int before = h3Requests.get();
+          HTTPSampleResult warmup = sample(client, sampler, url);
+          assertThat(warmup.isSuccessful()).isTrue();
+          http3Attempted = h3Requests.get() > before;
+        }
+        assertThat(http3Attempted)
+            .as("the origin must be reaching HTTP/3 before the cooldown can be shown to stop it")
+            .isTrue();
 
         markHttp3Broken(client, url.toURI());
+        int h3RequestsWhenBroken = h3Requests.get();
 
         HTTPSampleResult second = sample(client, sampler, url);
         assertThat(second.isSuccessful()).isTrue();
         assertThat(second.getResponseHeaders()).startsWith("HTTP/2");
-        assertThat(h3Requests.get()).isEqualTo(0);
+        assertThat(h3Requests.get())
+            .as("no HTTP/3 may be attempted once the origin is in the broken cooldown")
+            .isEqualTo(h3RequestsWhenBroken);
       } finally {
         client.stop();
       }