example.com/latemigrate/v2 v2.0.1
written by hand

This repository migrated to modules in v2.0.1 after v2.0.0 was already tagged.
All versions require rsc.io/quote so we can test downgrades.

v2.0.1 belongs to example.com/latemigrate/v2.

-- .mod --
module example.com/latemigrate/v2

require rsc.io/quote v1.3.0
-- .info --
{"Version":"v2.0.1"}
-- go.mod --
module example.com/latemigrate/v2

require rsc.io/quote v1.3.0

example.com/latemigrate/v2 v2.0.0
written by hand

This repository migrated to modules in v2.0.1 after v2.0.0 was already tagged.
All versions require rsc.io/quote so we can test downgrades.

v2.0.0 is technically part of example.com/latemigrate as v2.0.0+incompatible.
Proxies may serve it as part of the version list for example.com/latemigrate/v2.
'go get' must be able to ignore these versions.

-- .mod --
module example.com/latemigrate
-- .info --

utility bundled with the image.

In addition to the latest etcd version, each `registry.k8s.io/etcd` image contains
etcd and etcdctl binaries for older versions of etcd. These are used by the
migration operator utility when performing downgrades and multi-step upgrades,
but can also be used as the etcd target version.

#### Usage

Always run `/usr/local/bin/migrate` (or the
`/usr/local/bin/migrate-if-needed.sh` wrapper script) before starting the etcd

		target: target,
		list:   downgraded,
		Reqs:   reqs,
	})
	if err != nil {
		return nil, err
	}
	actualVersion := make(map[string]string, len(actual))
	for _, m := range actual {
		actualVersion[m.Path] = m.Version
	}

	downgraded = downgraded[:0]
	for _, m := range list {
		if v, ok := actualVersion[m.Path]; ok {
			downgraded = append(downgraded, module.Version{Path: m.Path, Version: v})
		}

				)
			}
		})
	}
}

func TestFormatErrMsg(t *testing.T) {
	errMsg1 := "specified version to upgrade to v1.9.0-alpha.3 is equal to or lower than the cluster version v1.10.0-alpha.0.69+638add6ddfb6d2. Downgrades are not supported yet"
	errMsg2 := "specified version to upgrade to v1.9.0-alpha.3 is higher than the kubeadm version v1.9.0-alpha.1.3121+84178212527295-dirty. Upgrade kubeadm first using the tool you used to install kubeadm"

#   \      \
#    \      \
#     ----- c.1 ---- d.2
#
# b.1 ---- c.2
#
# If we downgrade module d to version 1, we must downgrade b as well.
# If that downgrade selects b version 1, we will upgrade module c to version 2.

cp go.mod go.mod.orig
go mod tidy
cmp go.mod.orig go.mod

# Downgrading d to version 1 downgrades b, which upgrades c.
go get example.com/d@v0.1.0
go list -m all
stdout '^example.com/b v0.1.0 '

# (the version required by a.1) and running 'go mod tidy'.
# It is still selected at v0.1.0 (as a dependency of a),
# but its dependency on c is now pruned from the module graph, so it doesn't
# result in any downgrades to b or a if we run 'go get c@none'.

cp go.mod.orig go.mod
go mod edit -go=1.17

go list -m all
stdout '^example.com/a v0.1.0 '
stdout '^example.com/b v0.3.0 '
stdout '^example.com/c v0.2.0 '

B3: D2
C1: B2.hidden
C2: D2
D1:
D2:
build A1: A1 B3 D2
downgrade A1 D1: A1 B1 D1 E1
build A: A B3 C2 D2
downgrade A D1: A B2.hidden C1 D1

# Both B3 and C3 require D2.
# If we downgrade D to D1, then in isolation B3 would downgrade to B1,
# and C3 would downgrade to C1.
# But C1 requires B2.hidden, and B1 requires C2.hidden, so we can't
# downgrade to either of those without pulling the other back up a little.
#

#   \      \
#    \      \
#     ----- c.1 ---- d.2
#
# b.1 ---- c.2
#
# If we downgrade module d to version 1, we must downgrade b as well.
# If that downgrade selects b version 1, we will upgrade module c to version 2.

cp go.mod go.mod.orig
go mod tidy
cmp go.mod.orig go.mod

# Downgrading d to version 1 downgrades b, which upgrades c.
go get -v example.com/d@v0.1.0
go list -m all
stdout '^example.com/b v0.1.0 '

		// warning: v2->v3 ha upgrades not currently supported.
		{"ha-v3-v3-up", 3, "3.0.17/etcd3", "3.1.12/etcd3", "https", ""},

		// downgrades
		{"v3-v3-down", 1, "3.1.12/etcd3", "3.0.17/etcd3", "https", ""},

		// warning: ha downgrades not yet supported.
	}

	for _, m := range migrations {
		t.Run(m.title, func(t *testing.T) {
			start := mustParseEtcdVersionPair(m.startVersion)