From 97cf0225e81f80e67a42279699c93df9bfa32b9a Mon Sep 17 00:00:00 2001
From: Twaik Yont <9674930+twaik@users.noreply.github.com>
Date: Sun, 11 Oct 2026 22:46:47 +0300
Subject: [PATCH] deb: split Debian revision at the last hyphen

Per Debian Policy, the version is split at the last hyphen:
https://www.debian.org/doc/debian-policy/ch-controlfields.html#version

Add tests for the ordering of '+', which is a regular non-letter sorted by its ASCII value (see Comparing version numbers on the same page).
---
 deb/version.go      |  2 +-
 deb/version_test.go | 17 ++++++++++++++---
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/deb/version.go b/deb/version.go
index 4b9150389..b354855d7 100644
--- a/deb/version.go
+++ b/deb/version.go
@@ -35,7 +35,7 @@ func parseVersion(ver string) (epoch, upstream, debian string) {
 		epoch, ver = ver[:i], ver[i+1:]
 	}
 
-	i = strings.Index(ver, "-")
+	i = strings.LastIndex(ver, "-")
 	if i != -1 {
 		debian, ver = ver[i+1:], ver[:i]
 	}
diff --git a/deb/version_test.go b/deb/version_test.go
index 5b0692313..843b6554e 100644
--- a/deb/version_test.go
+++ b/deb/version_test.go
@@ -20,10 +20,10 @@ func (s *VersionSuite) TestParseVersion(c *C) {
 	c.Check([]string{e, u, d}, DeepEquals, []string{"", "1.3.4", "1"})
 
 	e, u, d = parseVersion("1.3-pre4-1")
-	c.Check([]string{e, u, d}, DeepEquals, []string{"", "1.3", "pre4-1"})
+	c.Check([]string{e, u, d}, DeepEquals, []string{"", "1.3-pre4", "1"})
 
 	e, u, d = parseVersion("4:1.3-pre4-1")
-	c.Check([]string{e, u, d}, DeepEquals, []string{"4", "1.3", "pre4-1"})
+	c.Check([]string{e, u, d}, DeepEquals, []string{"4", "1.3-pre4", "1"})
 }
 
 func (s *VersionSuite) TestCompareLexicographic(c *C) {
@@ -100,7 +100,18 @@ func (s *VersionSuite) TestCompareVersions(c *C) {
 	c.Check(CompareVersions("1.0-133-avc", "1.0"), Equals, 1)
 
 	c.Check(CompareVersions("5.2.0.3", "5.2.0.283"), Equals, -1)
-	c.Check(CompareVersions("4.3.5a", "4.3.5-rc3-1"), Equals, 1)
+	c.Check(CompareVersions("4.3.5a", "4.3.5-rc3-1"), Equals, -1)
+	c.Check(CompareVersions("1.6.0-rc1+really1.6.0-0", "1.6.0-rc1-0"), Equals, 1)
+	c.Check(CompareVersions("1.2-3-4", "1.2-3-5"), Equals, -1)
+	c.Check(CompareVersions("1.0-1-1", "1.0-1"), Equals, 1)
+	c.Check(CompareVersions("1.0+1", "1.0"), Equals, 1)
+	c.Check(CompareVersions("1.0+a-1", "1.0-a-1"), Equals, -1)
+	c.Check(CompareVersions("1.0+1-1", "1.0-1"), Equals, 1)
+	c.Check(CompareVersions("1.0-1+b1", "1.0-1"), Equals, 1)
+	c.Check(CompareVersions("1.0-1+b1", "1.0-1~bpo1"), Equals, 1)
+	c.Check(CompareVersions("1.0-1+b2", "1.0-1+b10"), Equals, -1)
+	c.Check(CompareVersions("1.0.1+dfsg-1", "1.0.1-1"), Equals, 1)
+	c.Check(CompareVersions("1.0-1+b1", "1.0-2"), Equals, -1)
 }
 
 func (s *VersionSuite) TestParseDependency(c *C) {