test

exporter/opentelemetry-exporter-prometheus/tests/test_prometheus_exporter.py

@@ -436,3 +436,27 @@ def test_target_info_sanitize(self):
             prometheus_metric.samples[0].labels["ratio"],
             "0.1",
         )
+
+    def test_label_order_does_not_matter(self):
+        metric_reader = PrometheusMetricReader()
+        provider = MeterProvider(metric_readers=[metric_reader])
+        meter = provider.get_meter("getting-started", "0.1.2")
+        counter = meter.create_counter("counter")
+
+        counter.add(1, {'cause': 'cause1', 'reason': 'reason1'})
+        counter.add(1, {'reason': 'reason2', 'cause': 'cause2'})
+
+        prometheus_output = generate_latest().decode()
+
+        for line in prometheus_output.split('\n'):
+            print(line)
+
+        # All labels are mapped correctly
+        self.assertIn('cause="cause1"', prometheus_output)
+        self.assertIn('cause="cause2"', prometheus_output)
+        self.assertIn('reason="reason1"', prometheus_output)
+        self.assertIn('reason="reason2"', prometheus_output)
+
+        # Only one metric is generated
+        metric_count = prometheus_output.count('# HELP counter_total')
+        self.assertEqual(metric_count, 1)