From 47c6d6bf44e91c57525767a3787d0cdeee946f8b Mon Sep 17 00:00:00 2001
From: hipocoro <hipocoro@sre.pm>
Date: Sat, 10 Aug 2024 14:07:23 +0200
Subject: [PATCH] fix: avoid duplicate buckets in histogram

---
 lib/histogram.js      |  2 +-
 test/histogramTest.js | 14 ++++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/lib/histogram.js b/lib/histogram.js
index 539620c2..cefc6c41 100644
--- a/lib/histogram.js
+++ b/lib/histogram.js
@@ -32,7 +32,7 @@ class Histogram extends Metric {
 			}
 		}
 
-		this.upperBounds = this.buckets;
+		this.upperBounds = [...new Set(this.buckets)];
 		this.bucketValues = this.upperBounds.reduce((acc, upperBound) => {
 			acc[upperBound] = 0;
 			return acc;
diff --git a/test/histogramTest.js b/test/histogramTest.js
index 5ec89f97..07434764 100644
--- a/test/histogramTest.js
+++ b/test/histogramTest.js
@@ -92,6 +92,20 @@ describe.each([
 				expect(values[1].labels.le).toEqual(5);
 				expect(values[2].labels.le).toEqual('+Inf');
 			});
+
+			it('should not have repeated LE buckets', async () => {
+				const histogram = new Histogram({
+					name: 'test_histogram_2',
+					help: 'test',
+					buckets: [1, 1, 5],
+				});
+				histogram.observe(6);
+				const values = (await histogram.get()).values;
+				expect(values[0].labels.le).toEqual(1);
+				expect(values[1].labels.le).toEqual(5);
+				expect(values[2].labels.le).toEqual('+Inf');
+			});
+
 			it('should group counts on each label set', async () => {
 				const histogram = new Histogram({
 					name: 'test_histogram_2',