lib/email: realign all structs

The only exported type that changes is the type Field, from consuming
128 to 120 bytes (-8 bytes).
Its only -8 bytes but it will used multiple times in the Header.

The rest changes are on the test files.

4 files changed, 19 insertions, 17 deletions

diff --git a/lib/email/contenttype_test.go b/lib/email/contenttype_test.go
index 8ebf7198..2dd36a58 100644
--- a/lib/email/contenttype_test.go
+++ b/lib/email/contenttype_test.go
@@ -12,9 +12,9 @@ import (
 
 func TestParseContentType(t *testing.T) {
 	cases := []struct {
-		in     []byte
 		expErr string
 		exp    string
+		in     []byte
 	}{{
 		exp: "text/plain; charset=us-ascii",
 	}, {
diff --git a/lib/email/field.go b/lib/email/field.go
index a57a7ba0..b0a94d47 100644
--- a/lib/email/field.go
+++ b/lib/email/field.go
@@ -20,8 +20,13 @@ import (
 // Field represent field name and value in header.
 //
 type Field struct {
-	// Type of field, the numeric representation of field name.
-	Type FieldType
+	// ContentType contains unpacked value of field with Name
+	// "Content-Type" or nil if still packed.
+	ContentType *ContentType
+
+	date   *time.Time
+	mboxes []*Mailbox
+
 	// Name contains "relaxed" canonicalization of field name.
 	Name []byte
 	// Value contains "relaxed" canonicalization of field value.
@@ -32,12 +37,8 @@ type Field struct {
 	// oriValue contains "simple" canonicalization of field value.
 	oriValue []byte
 
-	date   *time.Time
-	mboxes []*Mailbox
-
-	// ContentType contains unpacked value of field with Name
-	// "Content-Type" or nil if still packed.
-	ContentType *ContentType
+	// Type of field, the numeric representation of field name.
+	Type FieldType
 
 	// true if field.unpack has been called, false when field.setValue is
 	// called again.
diff --git a/lib/email/field_test.go b/lib/email/field_test.go
index ee08dffc..52fcac6d 100644
--- a/lib/email/field_test.go
+++ b/lib/email/field_test.go
@@ -142,10 +142,10 @@ func TestParseField(t *testing.T) {
 
 func TestUnpackDate(t *testing.T) {
 	cases := []struct {
-		desc   string
-		value  []byte
 		exp    time.Time
 		expErr string
+		desc   string
+		value  []byte
 	}{{
 		desc:   "With empty value",
 		expErr: "unpackDate: empty date",
@@ -256,9 +256,9 @@ func TestUnpackDate(t *testing.T) {
 
 func TestUnpackMailbox(t *testing.T) {
 	cases := []struct {
-		in     []byte
 		expErr string
 		exp    string
+		in     []byte
 	}{{
 		in:     []byte("Sender: local\r\n"),
 		expErr: `ParseMailboxes "local": empty or invalid address`,
@@ -291,9 +291,9 @@ func TestUnpackMailbox(t *testing.T) {
 
 func TestUnpackMailboxList(t *testing.T) {
 	cases := []struct {
-		in     []byte
 		expErr string
 		exp    string
+		in     []byte
 	}{{
 		in:     []byte("From: \r\n"),
 		expErr: "email: empty field value at 'From: \r\n'",
@@ -323,9 +323,9 @@ func TestUnpackMailboxList(t *testing.T) {
 
 func TestUnpackContentType(t *testing.T) {
 	cases := []struct {
-		in     []byte
 		expErr string
 		exp    string
+		in     []byte
 	}{{
 		in:     []byte("Content-Type: text;\r\n"),
 		expErr: "ParseContentType: missing subtype",
diff --git a/lib/email/message_test.go b/lib/email/message_test.go
index 5822d5b1..26ad9f81 100644
--- a/lib/email/message_test.go
+++ b/lib/email/message_test.go
@@ -114,9 +114,9 @@ func TestMessageDKIMVerify(t *testing.T) {
 	t.Skip()
 
 	cases := []struct {
+		expStatus *dkim.Status
 		inFile    string
 		expErr    string
-		expStatus *dkim.Status
 	}{{
 		inFile: "testdata/message-dkimverify-00.txt",
 		expStatus: &dkim.Status{
@@ -157,11 +157,12 @@ func TestMessageDKIMSign(t *testing.T) {
 	canonSimple := dkim.CanonSimple
 
 	cases := []struct {
+		sig       *dkim.Signature
+		expStatus *dkim.Status
+
 		inFile       string
-		sig          *dkim.Signature
 		expBodyHash  string
 		expSignature string
-		expStatus    *dkim.Status
 	}{{
 		inFile: "testdata/message-dkimsign-00.txt",
 		sig: &dkim.Signature{