Remove direct dependency on pflag

We weren't actually using pflag, except as an interface assertion.  This
makes it more obvious that pflag isn't actually used.

Author: DirectXMan12

go.mod

@@ -14,8 +14,6 @@ require (
 	github.com/onsi/gomega v1.8.1
 	github.com/prometheus/client_golang v1.0.0
 	github.com/prometheus/client_model v0.2.0
-	github.com/spf13/pflag v1.0.5
-	go.uber.org/atomic v1.4.0 // indirect
 	go.uber.org/zap v1.10.0
 	golang.org/x/time v0.0.0-20190308202827-9d24e82272b4
 	gomodules.xyz/jsonpatch/v2 v2.0.1

go.sum

@@ -319,8 +319,6 @@ go.mongodb.org/mongo-driver v1.1.2/go.mod h1:u7ryQJ+DOzQmeO7zB6MHyr8jkEQvC8vH7qL
 go.opencensus.io v0.21.0/go.mod h1:mSImk1erAIZhrmZN+AvHh14ztQfjbGwt4TtuofqLduU=
 go.uber.org/atomic v1.3.2 h1:2Oa65PReHzfn29GpvgsYwloV9AVFHPDk8tYxt2c2tr4=
 go.uber.org/atomic v1.3.2/go.mod h1:gD2HeocX3+yG+ygLZcrzQJaqmWj9AIm7n08wl/qW/PE=
-go.uber.org/atomic v1.4.0 h1:cxzIVoETapQEqDhQu3QfnvXAV4AlzcvUCxkVUFw3+EU=
-go.uber.org/atomic v1.4.0/go.mod h1:gD2HeocX3+yG+ygLZcrzQJaqmWj9AIm7n08wl/qW/PE=
 go.uber.org/multierr v1.1.0 h1:HoEmRHQPVSqub6w2z2d2EOVs2fjyFRGyofhKuyDq0QI=
 go.uber.org/multierr v1.1.0/go.mod h1:wR5kodmAFQ0UK8QlbwjlSNy0Z68gJhDJUG5sjR94q/0=
 go.uber.org/zap v1.10.0 h1:ORx85nbTijNz8ljznvCMR1ZBIPKFn3jQrag10X2AsuM=

pkg/log/zap/flags.go

@@ -23,11 +23,13 @@ import (
 	"strconv"
 	"strings"
 
-	"github.com/spf13/pflag"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
 )
 
+// each of these flags also should implement the flag.Value, as well
+// as pflag.Value for convinience.
+
 var levelStrings = map[string]zapcore.Level{
 	"debug":  zap.DebugLevel,
 	"-1":     zap.DebugLevel,
@@ -46,8 +48,6 @@ type encoderFlag struct {
 	value   string
 }
 
-var _ pflag.Value = &encoderFlag{}
-
 func (ev *encoderFlag) String() string {
 	return ev.value
 }
@@ -85,8 +85,6 @@ type levelFlag struct {
 	value   string
 }
 
-var _ pflag.Value = &levelFlag{}
-
 func (ev *levelFlag) Set(flagValue string) error {
 	level, validLevel := levelStrings[strings.ToLower(flagValue)]
 	if !validLevel {
@@ -119,8 +117,6 @@ type stackTraceFlag struct {
 	value   string
 }
 
-var _ pflag.Value = &stackTraceFlag{}
-
 func (ev *stackTraceFlag) Set(flagValue string) error {
 	level, validLevel := levelStrings[strings.ToLower(flagValue)]
 	if !validLevel {