Pin every terminal state, not just the two being fixed

The seven states #4298 made terminal had no test. A future edit that drops
one back to a bare log would only show up as a hung export in the field.

The companion case covers the other direction: progress states must not
decide the result on their own, or a response arriving after them would
never be consulted.

Author: thc1006

exporters/elasticsearch/test/es_log_record_exporter_test.cc

@@ -280,6 +280,48 @@ TEST(ElasticsearchLogsExporterSyncTests, ReadErrorEndsTheWait)
   EXPECT_EQ(result, opentelemetry::sdk::common::ExportResult::kFailure);
 }
 
+// The whole contract in one place. Every state that ends a session has to leave a result behind,
+// otherwise a client that emits it last strands the wait. The seven states other than the two
+// this change adds have behaved this way since #4298 but had no test.
+//
+// A regression here surfaces as a CTest timeout rather than a failed assertion, because a state
+// that stops being terminal leaves Export() waiting with nothing left to wake it.
+TEST(ElasticsearchLogsExporterSyncTests, EveryTerminalStateEndsTheWaitInFailure)
+{
+  SKIP_WITHOUT_SYNC_EXPORT();
+  const http_client::SessionState terminal[] = {
+      http_client::SessionState::CreateFailed, http_client::SessionState::ConnectFailed,
+      http_client::SessionState::SendFailed,   http_client::SessionState::SSLHandshakeFailed,
+      http_client::SessionState::TimedOut,     http_client::SessionState::NetworkError,
+      http_client::SessionState::Cancelled,    http_client::SessionState::ReadError,
+      http_client::SessionState::WriteError,   http_client::SessionState::Destroyed};
+
+  for (const auto state : terminal)
+  {
+    SCOPED_TRACE(static_cast<int>(state));
+    const auto result =
+        ExportWith([state](http_client::EventHandler &handler) { handler.OnEvent(state, ""); });
+    EXPECT_EQ(result, opentelemetry::sdk::common::ExportResult::kFailure);
+  }
+}
+
+// The other side of the same contract: a state that only reports progress must not complete the
+// export on its own, or a response that arrives afterwards is never consulted.
+TEST(ElasticsearchLogsExporterSyncTests, ProgressStatesDoNotDecideTheResult)
+{
+  SKIP_WITHOUT_SYNC_EXPORT();
+  const auto result = ExportWith([](http_client::EventHandler &handler) {
+    handler.OnEvent(http_client::SessionState::Created, "");
+    handler.OnEvent(http_client::SessionState::Connecting, "");
+    handler.OnEvent(http_client::SessionState::Connected, "");
+    handler.OnEvent(http_client::SessionState::Sending, "");
+    handler.OnEvent(http_client::SessionState::Response, "");
+    FakeResponse response(200, kAcceptedBody);
+    handler.OnResponse(response);
+  });
+  EXPECT_EQ(result, opentelemetry::sdk::common::ExportResult::kSuccess);
+}
+
 TEST(ElasticsearchLogsExporterSyncTests, WriteErrorEndsTheWait)
 {
   SKIP_WITHOUT_SYNC_EXPORT();