Use antithesis's random

tests/antithesis/Makefile

@@ -26,7 +26,8 @@ antithesis-build-etcd-image:
 		--build-arg GO_IMAGE_TAG=$(shell go work edit -json | jq .Go) \
 		--build-arg REF=$(REF) \
 		--tag etcd-server:latest \
-		$(ANTITHESIS_ROOT)/server/
+		-f ./server/Dockerfile \
+		$(ANTITHESIS_ROOT)
 
 .PHONY: antithesis-build-etcd-image-release-3.4
 antithesis-build-etcd-image-release-3.4: REF=release-3.4

tests/antithesis/pkg/go.mod

@@ -0,0 +1,5 @@
+module go.etcd.io/etcd/tests/v3/pkg
+
+go 1.26.4
+
+require github.com/antithesishq/antithesis-sdk-go v0.7.2

tests/antithesis/pkg/go.sum

@@ -0,0 +1,2 @@
+github.com/antithesishq/antithesis-sdk-go v0.7.2 h1:oEEedg1Xgi8drRjqB0f9tfjhLoInE0IYZfZ6zAhQUbY=
+github.com/antithesishq/antithesis-sdk-go v0.7.2/go.mod h1:FQyySiasQQM8735Ddel3MRojmy4dA1IqCeyJ5jmPMbI=

tests/antithesis/pkg/rand/rand.go

@@ -0,0 +1,89 @@
+// Copyright 2026 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package rand is a wrapper of https://antithesis.com/docs/generated/sdk/golang/random/
+// and provides the same functions as math/rand so it can be a drop-in replacement
+//
+// The usages of math/rand currently found in etcd (listing only the first occurence of each here)
+// to find all, use `for f in $(rg -l 'math/rand"'); do echo $f; grep 'rand\.' $f; done`
+//
+// 1. out = append(out, rand.Int63n(max-min)+min)
+// 2. r := rand.New(rand.NewSource(int64(time.Now().Nanosecond())))
+// 3. func shuffleEndpoints(r *rand.Rand, eps []string) []string {
+// 4. n := rand.Intn(3) + 3
+// 5. key := fmt.Sprintf("foo%d", rand.Int())
+// 6. membersToChange := rand.Perm(len(clus.Procs))[:numberOfMembersToChange]
+// 7. if _, err := rand.Read(v); err != nil {
+// 8. multiplier := jitter * (rand.Float64()*2 - 1)
+// 9. traceNum := rand.Int31()
+// 10. randID = rand.Uint64()
+// 11. rand.Shuffle(len(perm), func(i, j int) {
+package rand
+
+import (
+	mrand "math/rand"
+
+	antithesis "github.com/antithesishq/antithesis-sdk-go/random"
+)
+
+var (
+	src = antithesis.Source()
+	r   = mrand.New(src)
+)
+
+type Rand = mrand.Rand
+
+func New(_ mrand.Source) *mrand.Rand {
+	return r
+}
+
+func NewSource(_ int64) mrand.Source {
+	return src
+}
+
+func Int63n(n int64) int64 {
+	return r.Int63n(n)
+}
+
+func Uint64() uint64 {
+	return r.Uint64()
+}
+
+func Intn(n int) int {
+	return r.Intn(n)
+}
+
+func Int() int {
+	return r.Int()
+}
+
+func Perm(n int) []int {
+	return r.Perm(n)
+}
+
+func Read(p []byte) (n int, err error) {
+	return r.Read(p)
+}
+
+func Float64() float64 {
+	return r.Float64()
+}
+
+func Int31() int32 {
+	return r.Int31()
+}
+
+func Shuffle(n int, swap func(i, j int)) {
+	r.Shuffle(n, swap)
+}

tests/antithesis/pkg/rand/v2/randv2.go

@@ -0,0 +1,63 @@
+// Copyright 2026 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package rand is a wrapper of https://antithesis.com/docs/generated/sdk/golang/random/
+// and provides the same functions as math/rand/v2
+//
+// The usages of math/rand/v2 currently found in etcd
+//
+//  1. server/etcdserver/txn/util_bench_test.go
+//     rng := rand.New(rand.NewPCG(1, 2))
+//  2. tests/robustness/validate/operations_test.go
+//     rand.Shuffle(len(historyCopy), func(i, j int)
+//  3. tests/antithesis/test-template/robustness/traffic/main.go
+//     choice := rand.IntN(len(traffics))
+package rand
+
+import (
+	mrandv1 "math/rand"
+	mrandv2 "math/rand/v2"
+
+	antithesis "github.com/antithesishq/antithesis-sdk-go/random"
+)
+
+type sourceV2Func func() uint64
+
+func (f sourceV2Func) Uint64() uint64 {
+	return f()
+}
+
+// antithesis doesn't provide a math/rand/v2 source, so this is
+// needed for making a v1 source a v2.
+var (
+	v1Rand   = mrandv1.New(antithesis.Source())
+	v2Source = sourceV2Func(v1Rand.Uint64)
+	r        = mrandv2.New(v2Source)
+)
+
+func New(_ mrandv2.Source) *mrandv2.Rand {
+	return r
+}
+
+func NewPCG(_, _ int) mrandv2.Source {
+	return v2Source
+}
+
+func IntN(n int) int {
+	return r.IntN(n)
+}
+
+func Shuffle(n int, swap func(i, j int)) {
+	r.Shuffle(n, swap)
+}

tests/antithesis/server/Dockerfile

@@ -8,16 +8,24 @@ ARG REF=main
 RUN git clone --depth=1 https://github.com/etcd-io/etcd.git --branch=${REF} /etcd
 RUN go env -w GOTOOLCHAIN="go$(cat .go-version)"
 
-# inject assertions in place of gofail
+# Replacing math/rand with etcd's antithesis-sdk-go/random wrapper
+# See https://antithesis.com/docs/configuration/the_antithesis_environment/?sid=8fce.35&sterm=random&marks=Random#random-devices
+WORKDIR /etcd
+COPY pkg /etcd/tests/antithesis/pkg
+RUN find . -path "./tests/antithesis" -prune -type f -o -name 'go.mod' -type f -execdir go mod edit -replace=math/rand=$(git rev-parse --show-toplevel)/tests/antithesis/pkg/rand \;
+RUN find . -path "./tests/antithesis" -prune -type f -o -name 'go.mod' -type f -execdir go mod edit -replace=math/rand/v2=$(git rev-parse --show-toplevel)/tests/antithesis/pkg/rand/v2 \;
+RUN find . -name 'go.mod' -type f -execdir go mod tidy \;
+
+## inject assertions in place of gofail
 WORKDIR /etcd/server
 RUN go install golang.org/x/tools/cmd/goimports@latest
-RUN go get github.com/antithesishq/antithesis-sdk-go@v0.4.4
+RUN go get github.com/antithesishq/antithesis-sdk-go@v0.7.2
 RUN for file in $(grep -rl '// gofail'); do sed -i 's|\/\/ gofail.*var \([[:alnum:]]*\) .*|assert\.Reachable("\1", nil)|' $file; goimports -w $file; done
 RUN go mod tidy
 
 # replace verify with antithesis
 WORKDIR /etcd
-COPY inject/* .
+COPY server/inject/* .
 RUN if [ "${REF}" = "main" ]; then git apply *.patch; fi
 WORKDIR /etcd/client/pkg
 RUN go mod tidy