From fe3c4b97067d065e296dc321f55a7daf7243f011 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tom=C3=A1s=20Senart?= <tsenart@gmail.com>
Date: Thu, 5 Dec 2024 17:03:30 +0100
Subject: [PATCH] fixup! assert round-tripping

---
 bitset_test.go | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/bitset_test.go b/bitset_test.go
index 77ff334..309e429 100644
--- a/bitset_test.go
+++ b/bitset_test.go
@@ -2541,6 +2541,18 @@ func TestBitSetExtract(t *testing.T) {
 			if !dst.Equal(tc.expected) {
 				t.Errorf("got %v, expected %v", dst, tc.expected)
 			}
+
+			// Verify inverse relationship within the mask bits
+			deposited := New(tc.src.Len())
+			dst.DepositTo(tc.mask, deposited)
+
+			// Only bits selected by the mask should match between source and deposited
+			maskedSource := tc.src.Intersection(tc.mask)
+			maskedDeposited := deposited.Intersection(tc.mask)
+
+			if !maskedSource.Equal(maskedDeposited) {
+				t.Error("DepositTo(ExtractTo(x,m),m) doesn't preserve masked source bits")
+			}
 		})
 	}
 }
@@ -2657,6 +2669,14 @@ func TestBitSetDeposit(t *testing.T) {
 			if !dst.Equal(tc.expected) {
 				t.Errorf("got %v, expected %v", dst, tc.expected)
 			}
+
+			// Verify inverse relationship for set bits up to mask cardinality
+			extracted := New(tc.src.Len())
+			dst.ExtractTo(tc.mask, extracted)
+
+			if !extracted.Equal(tc.src) {
+				t.Error("ExtractTo(DepositTo(x,m),m) doesn't preserve source bits that were selected by mask")
+			}
 		})
 	}
 }