From ac0b1c60b40f92b33467133ad68d678026df6c6c Mon Sep 17 00:00:00 2001
From: Min Jin <minkimzz@amazon.com>
Date: Thu, 22 Oct 2026 10:27:27 -0700
Subject: [PATCH] fix(quantity): format negative quantities with SI/binary
 suffixes

QuantityFormatter.removeFactorsForBase used result.compareTo(base) >= 0
as the loop guard, which is always false for negative unscaled values, so
negative quantities were never reduced to a suffixed form. As a result
Quantity.toSuffixedString() returned e.g. "-100000" instead of "-100k"
and "-1048576" instead of "-1Mi".

Guard on the absolute value so the factor-removal loop runs for negative
magnitudes too. BigInteger.mod already returns a non-negative remainder
and divide handles negative values, so the divisibility check and
downstream exponent math are unchanged for positive inputs.

Add focused unit tests covering negative DECIMAL_SI and BINARY_SI
formatting (fail before, pass after).
---
 .../client/custom/QuantityFormatter.java         |  2 +-
 .../client/custom/QuantityFormatterTest.java     | 16 ++++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/kubernetes/src/main/java/io/kubernetes/client/custom/QuantityFormatter.java b/kubernetes/src/main/java/io/kubernetes/client/custom/QuantityFormatter.java
index 0f15eacad2..92f36ee089 100644
--- a/kubernetes/src/main/java/io/kubernetes/client/custom/QuantityFormatter.java
+++ b/kubernetes/src/main/java/io/kubernetes/client/custom/QuantityFormatter.java
@@ -99,7 +99,7 @@ private Pair<BigInteger, Integer> ensureExponentIsMultipleOf3(final BigInteger m
   private Pair<BigInteger, Integer> removeFactorsForBase(final BigInteger value, final BigInteger base) {
     int times = 0;
     BigInteger result = value;
-    while (result.compareTo(base) >= 0 && result.mod(base).equals(BigInteger.ZERO)) {
+    while (result.abs().compareTo(base) >= 0 && result.mod(base).equals(BigInteger.ZERO)) {
       times++;
       result = result.divide(base);
     }
diff --git a/kubernetes/src/test/java/io/kubernetes/client/custom/QuantityFormatterTest.java b/kubernetes/src/test/java/io/kubernetes/client/custom/QuantityFormatterTest.java
index 324dd225c9..3ce500c60f 100644
--- a/kubernetes/src/test/java/io/kubernetes/client/custom/QuantityFormatterTest.java
+++ b/kubernetes/src/test/java/io/kubernetes/client/custom/QuantityFormatterTest.java
@@ -155,6 +155,22 @@ void formatFractionalBinarySi() {
     assertThat(formattedString).isEqualTo("123123m");
   }
 
+  @Test
+  void formatNegativeDecimalSi() {
+    final String formattedString =
+        new QuantityFormatter()
+            .format(new Quantity(new BigDecimal("-100000"), Quantity.Format.DECIMAL_SI));
+    assertThat(formattedString).isEqualTo("-100k");
+  }
+
+  @Test
+  void formatNegativeBinarySi() {
+    final String formattedString =
+        new QuantityFormatter()
+            .format(new Quantity(new BigDecimal(2).pow(20).negate(), Quantity.Format.BINARY_SI));
+    assertThat(formattedString).isEqualTo("-1Mi");
+  }
+
   @Test
   void formatDecimalExponent() {
     final String formattedString =