diff --git a/log/format.go b/log/format.go
index bce4f439ad..b7c6baa570 100644
--- a/log/format.go
+++ b/log/format.go
@@ -24,6 +24,14 @@ const (
 	termCtxMaxPadding = 40
 )
 
+// ResetGlobalState resets the fieldPadding, which is useful for producing
+// predictable output.
+func ResetGlobalState() {
+	fieldPaddingLock.Lock()
+	fieldPadding = make(map[string]int)
+	fieldPaddingLock.Unlock()
+}
+
 // locationTrims are trimmed for display to avoid unwieldy log lines.
 var locationTrims = []string{
 	"github.com/XinFinOrg/XDPoSChain/",
diff --git a/log/format_test.go b/log/format_test.go
index e08c1d1a4a..41e1809c38 100644
--- a/log/format_test.go
+++ b/log/format_test.go
@@ -1,105 +1,10 @@
 package log
 
 import (
-	"fmt"
-	"math"
-	"math/big"
 	"math/rand"
-	"strings"
 	"testing"
-
-	"github.com/holiman/uint256"
 )
 
-func TestPrettyInt64(t *testing.T) {
-	tests := []struct {
-		n int64
-		s string
-	}{
-		{0, "0"},
-		{10, "10"},
-		{-10, "-10"},
-		{100, "100"},
-		{-100, "-100"},
-		{1000, "1000"},
-		{-1000, "-1000"},
-		{10000, "10000"},
-		{-10000, "-10000"},
-		{99999, "99999"},
-		{-99999, "-99999"},
-		{100000, "100,000"},
-		{-100000, "-100,000"},
-		{1000000, "1,000,000"},
-		{-1000000, "-1,000,000"},
-		{math.MaxInt64, "9,223,372,036,854,775,807"},
-		{math.MinInt64, "-9,223,372,036,854,775,808"},
-	}
-	for i, tt := range tests {
-		if have := FormatLogfmtInt64(tt.n); have != tt.s {
-			t.Errorf("test %d: format mismatch: have %s, want %s", i, have, tt.s)
-		}
-	}
-}
-
-func TestPrettyUint64(t *testing.T) {
-	tests := []struct {
-		n uint64
-		s string
-	}{
-		{0, "0"},
-		{10, "10"},
-		{100, "100"},
-		{1000, "1000"},
-		{10000, "10000"},
-		{99999, "99999"},
-		{100000, "100,000"},
-		{1000000, "1,000,000"},
-		{math.MaxUint64, "18,446,744,073,709,551,615"},
-	}
-	for i, tt := range tests {
-		if have := FormatLogfmtUint64(tt.n); have != tt.s {
-			t.Errorf("test %d: format mismatch: have %s, want %s", i, have, tt.s)
-		}
-	}
-}
-
-func TestPrettyBigInt(t *testing.T) {
-	tests := []struct {
-		int string
-		s   string
-	}{
-		{"111222333444555678999", "111,222,333,444,555,678,999"},
-		{"-111222333444555678999", "-111,222,333,444,555,678,999"},
-		{"11122233344455567899900", "11,122,233,344,455,567,899,900"},
-		{"-11122233344455567899900", "-11,122,233,344,455,567,899,900"},
-	}
-
-	for _, tt := range tests {
-		v, _ := new(big.Int).SetString(tt.int, 10)
-		if have := formatLogfmtBigInt(v); have != tt.s {
-			t.Errorf("invalid output %s, want %s", have, tt.s)
-		}
-	}
-}
-
-func TestPrettyUint256(t *testing.T) {
-	tests := []struct {
-		int string
-		s   string
-	}{
-		{"111222333444555678999", "111,222,333,444,555,678,999"},
-		{"11122233344455567899900", "11,122,233,344,455,567,899,900"},
-	}
-
-	for _, tt := range tests {
-		v := new(uint256.Int)
-		v.SetFromDecimal(tt.int)
-		if have := formatLogfmtUint256(v); have != tt.s {
-			t.Errorf("invalid output %s, want %s", have, tt.s)
-		}
-	}
-}
-
 var sink string
 
 func BenchmarkPrettyInt64Logfmt(b *testing.B) {
@@ -115,47 +20,3 @@ func BenchmarkPrettyUint64Logfmt(b *testing.B) {
 		sink = FormatLogfmtUint64(rand.Uint64())
 	}
 }
-
-func TestSanitation(t *testing.T) {
-	msg := "\u001b[1G\u001b[K\u001b[1A"
-	msg2 := "\u001b  \u0000"
-	msg3 := "NiceMessage"
-	msg4 := "Space Message"
-	msg5 := "Enter\nMessage"
-
-	for i, tt := range []struct {
-		msg  string
-		want string
-	}{
-		{
-			msg:  msg,
-			want: fmt.Sprintf("] %q                   %q=%q\n", msg, msg, msg),
-		},
-		{
-			msg:  msg2,
-			want: fmt.Sprintf("] %q                             %q=%q\n", msg2, msg2, msg2),
-		},
-		{
-			msg:  msg3,
-			want: fmt.Sprintf("] %s                              %s=%s\n", msg3, msg3, msg3),
-		},
-		{
-			msg:  msg4,
-			want: fmt.Sprintf("] %s                            %q=%q\n", msg4, msg4, msg4),
-		},
-		{
-			msg:  msg5,
-			want: fmt.Sprintf("] %s                            %q=%q\n", msg5, msg5, msg5),
-		},
-	} {
-		var (
-			logger = New()
-			out    = new(strings.Builder)
-		)
-		logger.SetHandler(LvlFilterHandler(LvlInfo, StreamHandler(out, TerminalFormat(false))))
-		logger.Info(tt.msg, tt.msg, tt.msg)
-		if have := out.String()[24:]; tt.want != have {
-			t.Fatalf("test %d: want / have: \n%v\n%v", i, tt.want, have)
-		}
-	}
-}