From 4fef7fcb9022156e41b395fff08045b1e53dedba Mon Sep 17 00:00:00 2001
From: vivekpatani <9080894+vivekpatani@users.noreply.github.com>
Date: Tue, 19 Jul 2022 15:57:21 -0700
Subject: [PATCH] clientv3: fix isOptsWithFromKey/isOptsWithPrefix

- Addressing: https://github.com/etcd-io/etcd/issues/13332
- Backporting: https://github.com/etcd-io/etcd/pull/13334

Signed-off-by: vivekpatani <9080894+vivekpatani@users.noreply.github.com>
---
 clientv3/op.go    | 27 +++++++++++++++++++++++++--
 clientv3/utils.go | 18 ------------------
 2 files changed, 25 insertions(+), 20 deletions(-)

diff --git a/clientv3/op.go b/clientv3/op.go
index 81ae31fd8..778617d4d 100644
--- a/clientv3/op.go
+++ b/clientv3/op.go
@@ -77,6 +77,9 @@ type Op struct {
 	cmps    []Cmp
 	thenOps []Op
 	elseOps []Op
+
+	isOptsWithFromKey bool
+	isOptsWithPrefix  bool
 }
 
 // accessors / mutators
@@ -216,6 +219,10 @@ func (op Op) isWrite() bool {
 	return op.t != tRange
 }
 
+func NewOp() *Op {
+	return &Op{key: []byte("")}
+}
+
 // OpGet returns "get" operation based on given key and operation options.
 func OpGet(key string, opts ...OpOption) Op {
 	// WithPrefix and WithFromKey are not supported together
@@ -387,6 +394,7 @@ func WithPrefix() OpOption {
 			return
 		}
 		op.end = getPrefix(op.key)
+		op.isOptsWithPrefix = true
 	}
 }
 
@@ -406,6 +414,7 @@ func WithFromKey() OpOption {
 			op.key = []byte{0}
 		}
 		op.end = []byte("\x00")
+		op.isOptsWithFromKey = true
 	}
 }
 
@@ -554,7 +563,21 @@ func toLeaseTimeToLiveRequest(id LeaseID, opts ...LeaseOption) *pb.LeaseTimeToLi
 }
 
 // isWithPrefix returns true if WithPrefix is being called in the op
-func isWithPrefix(opts []OpOption) bool { return isOpFuncCalled("WithPrefix", opts) }
+func isWithPrefix(opts []OpOption) bool {
+	ret := NewOp()
+	for _, opt := range opts {
+		opt(ret)
+	}
+
+	return ret.isOptsWithPrefix
+}
 
 // isWithFromKey returns true if WithFromKey is being called in the op
-func isWithFromKey(opts []OpOption) bool { return isOpFuncCalled("WithFromKey", opts) }
+func isWithFromKey(opts []OpOption) bool {
+	ret := NewOp()
+	for _, opt := range opts {
+		opt(ret)
+	}
+
+	return ret.isOptsWithFromKey
+}
diff --git a/clientv3/utils.go b/clientv3/utils.go
index b998c41b9..850275877 100644
--- a/clientv3/utils.go
+++ b/clientv3/utils.go
@@ -16,9 +16,6 @@ package clientv3
 
 import (
 	"math/rand"
-	"reflect"
-	"runtime"
-	"strings"
 	"time"
 )
 
@@ -32,18 +29,3 @@ func jitterUp(duration time.Duration, jitter float64) time.Duration {
 	multiplier := jitter * (rand.Float64()*2 - 1)
 	return time.Duration(float64(duration) * (1 + multiplier))
 }
-
-// Check if the provided function is being called in the op options.
-func isOpFuncCalled(op string, opts []OpOption) bool {
-	for _, opt := range opts {
-		v := reflect.ValueOf(opt)
-		if v.Kind() == reflect.Func {
-			if opFunc := runtime.FuncForPC(v.Pointer()); opFunc != nil {
-				if strings.Contains(opFunc.Name(), op) {
-					return true
-				}
-			}
-		}
-	}
-	return false
-}