builder_test.go

package enmime_test

import (
	"bytes"
	"net/mail"
	"path/filepath"
	"reflect"
	"strconv"
	"testing"
	"time"

	"github.com/jhillyerd/enmime"
	"github.com/jhillyerd/enmime/internal/test"
)

type mockSender struct {
	from string
	to   []string
	msg  []byte
}

func (s *mockSender) Send(from string, to []string, msg []byte) error {
	s.from = from
	s.to = to
	s.msg = msg
	return nil
}

var addrSlice = []mail.Address{{Name: "name", Address: "addr"}}

func TestBuilderEquals(t *testing.T) {
	a := enmime.Builder()
	b := enmime.Builder()
	if !a.Equals(b) {
		t.Error("New PartBuilders should be equal")
	}
}

func TestBuilderFrom(t *testing.T) {
	a := enmime.Builder().From("name", "same")
	b := enmime.Builder().From("name", "same")
	if !a.Equals(b) {
		t.Error("Same From(value) should be equal")
	}

	a = enmime.Builder().From("name", "foo")
	b = enmime.Builder().From("name", "bar")
	if a.Equals(b) {
		t.Error("Different From(value) should not be equal")
	}

	a = enmime.Builder().From("name", "foo")
	b = a.From("name", "bar")
	if a.Equals(b) {
		t.Error("From() should not mutate receiver, failed")
	}

	want := mail.Address{Name: "name", Address: "from@inbucket.org"}
	a = enmime.Builder().From(want.Name, want.Address).Subject("foo").ToAddrs(addrSlice)
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := p.Header.Get("From")
	if got != want.String() {
		t.Errorf("From: %q, want: %q", got, want)
	}
}

func TestBuilderSubject(t *testing.T) {
	a := enmime.Builder().Subject("same")
	b := enmime.Builder().Subject("same")
	if !a.Equals(b) {
		t.Error("Same Subject(value) should be equal")
	}

	a = enmime.Builder().Subject("foo")
	b = enmime.Builder().Subject("bar")
	if a.Equals(b) {
		t.Error("Different Subject(value) should not be equal")
	}

	a = enmime.Builder().Subject("foo")
	b = a.Subject("bar")
	if a.Equals(b) {
		t.Error("Subject() should not mutate receiver, failed")
	}

	want := "engaging subject"
	a = enmime.Builder().Subject(want).From("name", "foo").ToAddrs(addrSlice)
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := p.Header.Get("Subject")
	if got != want {
		t.Errorf("Subject: %q, want: %q", got, want)
	}
}

func TestBuilderDate(t *testing.T) {
	a := enmime.Builder().Date(time.Date(2017, 1, 1, 13, 14, 15, 16, time.UTC))
	b := enmime.Builder().Date(time.Date(2017, 1, 1, 13, 14, 15, 16, time.UTC))
	if !a.Equals(b) {
		t.Error("Same Date(value) should be equal")
	}

	a = enmime.Builder().Date(time.Date(2017, 1, 1, 13, 14, 15, 16, time.UTC))
	b = enmime.Builder().Date(time.Date(2018, 1, 1, 13, 14, 15, 16, time.UTC))
	if a.Equals(b) {
		t.Error("Different Date(value) should not be equal")
	}

	a = enmime.Builder().Date(time.Date(2017, 1, 1, 13, 14, 15, 16, time.UTC))
	b = a.Date(time.Date(2018, 1, 1, 13, 14, 15, 16, time.UTC))
	if a.Equals(b) {
		t.Error("Date() should not mutate receiver, failed")
	}

	input := time.Date(2017, 1, 1, 13, 14, 15, 16, time.UTC)
	want := "Sun, 01 Jan 2017 13:14:15 +0000"
	a = enmime.Builder().Date(input).Subject("hi").From("name", "foo").ToAddrs(addrSlice)
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := p.Header.Get("Date")
	if got != want {
		t.Errorf("Date: %q, want: %q", got, want)
	}
}

func TestBuilderTo(t *testing.T) {
	a := enmime.Builder().To("name", "same")
	b := enmime.Builder().To("name", "same")
	if !a.Equals(b) {
		t.Error("Same To(value) should be equal")
	}

	a = enmime.Builder().To("name", "foo")
	b = enmime.Builder().To("name", "bar")
	if a.Equals(b) {
		t.Error("Different To(value) should not be equal")
	}

	a = enmime.Builder().To("name", "foo")
	for i := 0; i < 1000; i++ {
		b = a.To("name", "bar"+strconv.Itoa(i))
		if a.Equals(b) {
			t.Error("To() should not mutate receiver, failed")
		}
		a = b
	}

	a = enmime.Builder().From("name", "foo").Subject("foo")
	a = a.To("one", "one@inbucket.org")
	a = a.To("two", "two@inbucket.org")
	want := "\"one\" <one@inbucket.org>, \"two\" <two@inbucket.org>"
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := p.Header.Get("To")
	if !reflect.DeepEqual(got, want) {
		t.Errorf("To: %q, want: %q", got, want)
	}
}

func TestBuilderToAddrs(t *testing.T) {
	a := enmime.Builder().ToAddrs([]mail.Address{{Name: "name", Address: "same"}})
	b := enmime.Builder().ToAddrs([]mail.Address{{Name: "name", Address: "same"}})
	if !a.Equals(b) {
		t.Error("Same To(value) should be equal")
	}

	a = enmime.Builder().ToAddrs([]mail.Address{{Name: "name", Address: "foo"}})
	b = enmime.Builder().ToAddrs([]mail.Address{{Name: "name", Address: "bar"}})
	if a.Equals(b) {
		t.Error("Different To(value) should not be equal")
	}

	a = enmime.Builder().ToAddrs([]mail.Address{{Name: "name", Address: "foo"}})
	b = a.ToAddrs([]mail.Address{{Name: "name", Address: "bar"}})
	if a.Equals(b) {
		t.Error("To() should not mutate receiver, failed")
	}

	input := []mail.Address{
		{Name: "one", Address: "one@inbucket.org"},
		{Name: "two", Address: "two@inbucket.org"},
	}
	want := "\"one\" <one@inbucket.org>, \"two\" <two@inbucket.org>"
	a = enmime.Builder().ToAddrs(input).From("name", "foo").Subject("foo")
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := p.Header.Get("To")
	if !reflect.DeepEqual(got, want) {
		t.Errorf("To: %q, want: %q", got, want)
	}
}

func TestBuilderCC(t *testing.T) {
	a := enmime.Builder().CC("name", "same")
	b := enmime.Builder().CC("name", "same")
	if !a.Equals(b) {
		t.Error("Same CC(value) should be equal")
	}

	a = enmime.Builder().CC("name", "foo")
	b = enmime.Builder().CC("name", "bar")
	if a.Equals(b) {
		t.Error("Different CC(value) should not be equal")
	}

	a = enmime.Builder().CC("name", "foo")
	b = a.CC("name", "bar")
	if a.Equals(b) {
		t.Error("CC() should not mutate receiver, failed")
	}

	a = enmime.Builder().From("name", "foo").Subject("foo")
	a = a.CC("one", "one@inbucket.org")
	a = a.CC("two", "two@inbucket.org")
	want := "\"one\" <one@inbucket.org>, \"two\" <two@inbucket.org>"
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := p.Header.Get("CC")
	if !reflect.DeepEqual(got, want) {
		t.Errorf("CC: %q, want: %q", got, want)
	}
}

func TestBuilderCCAddrs(t *testing.T) {
	a := enmime.Builder().CCAddrs([]mail.Address{{Name: "name", Address: "same"}})
	b := enmime.Builder().CCAddrs([]mail.Address{{Name: "name", Address: "same"}})
	if !a.Equals(b) {
		t.Error("Same CC(value) should be equal")
	}

	a = enmime.Builder().CCAddrs([]mail.Address{{Name: "name", Address: "foo"}})
	b = enmime.Builder().CCAddrs([]mail.Address{{Name: "name", Address: "bar"}})
	if a.Equals(b) {
		t.Error("Different CC(value) should not be equal")
	}

	a = enmime.Builder().CCAddrs([]mail.Address{{Name: "name", Address: "foo"}})
	b = a.CCAddrs([]mail.Address{{Name: "name", Address: "bar"}})
	if a.Equals(b) {
		t.Error("CC() should not mutate receiver, failed")
	}

	input := []mail.Address{
		{Name: "one", Address: "one@inbucket.org"},
		{Name: "two", Address: "two@inbucket.org"},
	}
	want := "\"one\" <one@inbucket.org>, \"two\" <two@inbucket.org>"
	a = enmime.Builder().CCAddrs(input).From("name", "foo").Subject("foo")
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := p.Header.Get("Cc")
	if !reflect.DeepEqual(got, want) {
		t.Errorf("CC: %q, want: %q", got, want)
	}
}

func TestBuilderBCC(t *testing.T) {
	a := enmime.Builder().BCC("name", "same")
	b := enmime.Builder().BCC("name", "same")
	if !a.Equals(b) {
		t.Error("Same BCC(value) should be equal")
	}

	a = enmime.Builder().BCC("name", "foo")
	b = enmime.Builder().BCC("name", "bar")
	if a.Equals(b) {
		t.Error("Different BCC(value) should not be equal")
	}

	a = enmime.Builder().BCC("name", "foo")
	b = a.BCC("name", "bar")
	if a.Equals(b) {
		t.Error("BCC() should not mutate receiver, failed")
	}

	a = enmime.Builder().From("name", "foo").Subject("foo")
	a = a.BCC("one", "one@inbucket.org")
	a = a.BCC("two", "two@inbucket.org")
	want := ""
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := p.Header.Get("BCC")
	if !reflect.DeepEqual(got, want) {
		t.Errorf("BCC: %q, want: %q", got, want)
	}
}

func TestBuilderBCCAddrs(t *testing.T) {
	a := enmime.Builder().BCCAddrs([]mail.Address{{Name: "name", Address: "same"}})
	b := enmime.Builder().BCCAddrs([]mail.Address{{Name: "name", Address: "same"}})
	if !a.Equals(b) {
		t.Error("Same BCC(value) should be equal")
	}

	a = enmime.Builder().BCCAddrs([]mail.Address{{Name: "name", Address: "foo"}})
	b = enmime.Builder().BCCAddrs([]mail.Address{{Name: "name", Address: "bar"}})
	if a.Equals(b) {
		t.Error("Different BCC(value) should not be equal")
	}

	a = enmime.Builder().BCCAddrs([]mail.Address{{Name: "name", Address: "foo"}})
	b = a.BCCAddrs([]mail.Address{{Name: "name", Address: "bar"}})
	if a.Equals(b) {
		t.Error("BCC() should not mutate receiver, failed")
	}

	// BCC doesn't show up in headers
	input := []mail.Address{
		{Name: "one", Address: "one@inbucket.org"},
		{Name: "two", Address: "two@inbucket.org"},
	}
	want := ""
	a = enmime.Builder().BCCAddrs(input).From("name", "foo").Subject("foo")
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := p.Header.Get("Bcc")
	if !reflect.DeepEqual(got, want) {
		t.Errorf("BCC: %q, want: %q", got, want)
	}
}

func TestBuilderReplyTo(t *testing.T) {
	a := enmime.Builder().ReplyTo("name", "same")
	b := enmime.Builder().ReplyTo("name", "same")
	if !a.Equals(b) {
		t.Error("Same ReplyTo(value) should be equal")
	}

	a = enmime.Builder().ReplyTo("name", "foo")
	b = enmime.Builder().ReplyTo("name", "bar")
	if a.Equals(b) {
		t.Error("Different ReplyTo(value) should not be equal")
	}

	a = enmime.Builder().ReplyTo("name", "foo")
	b = a.ReplyTo("name", "bar")
	if a.Equals(b) {
		t.Error("ReplyTo() should not mutate receiver, failed")
	}

	a = enmime.Builder().ToAddrs(addrSlice).From("name", "foo").Subject("foo")
	a = a.ReplyTo("one", "one@inbucket.org")
	want := "\"one\" <one@inbucket.org>"
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := p.Header.Get("Reply-To")
	if got != want {
		t.Errorf("Reply-To: %q, want: %q", got, want)
	}
}

func TestBuilderText(t *testing.T) {
	a := enmime.Builder().Text([]byte("same"))
	b := enmime.Builder().Text([]byte("same"))
	if !a.Equals(b) {
		t.Error("Same Text(value) should be equal")
	}

	a = enmime.Builder().Text([]byte("foo"))
	b = enmime.Builder().Text([]byte("bar"))
	if a.Equals(b) {
		t.Error("Different Text(value) should not be equal")
	}

	a = enmime.Builder().Text([]byte("foo"))
	b = a.Text([]byte("bar"))
	if a.Equals(b) {
		t.Error("Text() should not mutate receiver, failed")
	}

	want := "test text body"
	a = enmime.Builder().Text([]byte(want)).From("name", "foo").Subject("foo").ToAddrs(addrSlice)
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := string(p.Content)
	if got != want {
		t.Errorf("Content: %q, want: %q", got, want)
	}
	want = "text/plain"
	got = p.ContentType
	if got != want {
		t.Errorf("Content-Type: %q, want: %q", got, want)
	}
	want = "utf-8"
	got = p.Charset
	if got != want {
		t.Errorf("Charset: %q, want: %q", got, want)
	}
}

func TestBuilderHTML(t *testing.T) {
	a := enmime.Builder().HTML([]byte("same"))
	b := enmime.Builder().HTML([]byte("same"))
	if !a.Equals(b) {
		t.Error("Same HTML(value) should be equal")
	}

	a = enmime.Builder().HTML([]byte("foo"))
	b = enmime.Builder().HTML([]byte("bar"))
	if a.Equals(b) {
		t.Error("Different HTML(value) should not be equal")
	}

	a = enmime.Builder().HTML([]byte("foo"))
	b = a.HTML([]byte("bar"))
	if a.Equals(b) {
		t.Error("HTML() should not mutate receiver, failed")
	}

	want := "test html body"
	a = enmime.Builder().HTML([]byte(want)).From("name", "foo").Subject("foo").ToAddrs(addrSlice)
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := string(p.Content)
	if got != want {
		t.Errorf("Content: %q, want: %q", got, want)
	}
	want = "text/html"
	got = p.ContentType
	if got != want {
		t.Errorf("Content-Type: %q, want: %q", got, want)
	}
	want = "utf-8"
	got = p.Charset
	if got != want {
		t.Errorf("Charset: %q, want: %q", got, want)
	}
}

func TestBuilderMultiBody(t *testing.T) {
	text := "test text body"
	html := "test html body"
	a := enmime.Builder().
		Text([]byte(text)).
		HTML([]byte(html)).
		From("name", "foo").
		Subject("foo").
		ToAddrs(addrSlice)
	root, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}

	// Should be multipart
	p := root
	want := "multipart/alternative"
	got := p.ContentType
	if got != want {
		t.Errorf("Content-Type: %q, want: %q", got, want)
	}

	// Find text part
	p = root.DepthMatchFirst(func(p *enmime.Part) bool { return p.ContentType == "text/plain" })
	if p == nil {
		t.Fatal("Did not find a text/plain part")
	}
	want = text
	got = string(p.Content)
	if got != want {
		t.Errorf("Content: %q, want: %q", got, want)
	}
	want = "utf-8"
	got = p.Charset
	if got != want {
		t.Errorf("Charset: %q, want: %q", got, want)
	}

	// Find HTML part
	p = root.DepthMatchFirst(func(p *enmime.Part) bool { return p.ContentType == "text/html" })
	if p == nil {
		t.Fatal("Did not find a text/html part")
	}
	want = html
	got = string(p.Content)
	if got != want {
		t.Errorf("Content: %q, want: %q", got, want)
	}
	want = "utf-8"
	got = p.Charset
	if got != want {
		t.Errorf("Charset: %q, want: %q", got, want)
	}
}

func TestBuilderAddAttachment(t *testing.T) {
	a := enmime.Builder().AddAttachment([]byte("same"), "ct", "fn")
	b := enmime.Builder().AddAttachment([]byte("same"), "ct", "fn")
	if !a.Equals(b) {
		t.Error("Same AddAttachment(value) should be equal")
	}

	a = enmime.Builder().AddAttachment([]byte("foo"), "ct", "fn")
	b = enmime.Builder().AddAttachment([]byte("bar"), "ct", "fn")
	if a.Equals(b) {
		t.Error("Different AddAttachment(value) should not be equal")
	}

	a = enmime.Builder().AddAttachment([]byte("foo"), "ct", "fn")
	b = a.AddAttachment([]byte("bar"), "ct", "fn")
	b1 := b.AddAttachment([]byte("baz"), "ct", "fn")
	b2 := b.AddAttachment([]byte("bax"), "ct", "fn")
	if a.Equals(b) || b.Equals(b1) || b1.Equals(b2) {
		t.Error("AddAttachment() should not mutate receiver, failed")
	}

	want := "fake JPG data"
	name := "photo.jpg"
	disposition := "attachment"
	a = enmime.Builder().
		Text([]byte("text")).
		HTML([]byte("html")).
		From("name", "foo").
		Subject("foo").
		ToAddrs(addrSlice).
		AddAttachment([]byte(want), "image/jpeg", name)
	root, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	p := root.DepthMatchFirst(func(p *enmime.Part) bool { return p.FileName == name })
	if p == nil {
		t.Fatalf("Did not find a %q part", name)
	}
	if p.Disposition != disposition {
		t.Errorf("Content disposition: %s, want: %s", p.Disposition, disposition)
	}
	got := string(p.Content)
	if got != want {
		t.Errorf("Content: %q, want: %q", got, want)
	}

	// Check structure
	wantTypes := []string{
		"multipart/mixed",
		"multipart/alternative",
		"text/plain",
		"text/html",
		"image/jpeg",
	}
	gotParts := root.DepthMatchAll(func(p *enmime.Part) bool { return true })
	gotTypes := make([]string, 0)
	for _, p := range gotParts {
		gotTypes = append(gotTypes, p.ContentType)
	}
	test.DiffStrings(t, gotTypes, wantTypes)
}

func TestBuilderAddFileAttachment(t *testing.T) {
	a := enmime.Builder().AddFileAttachment("zzzDOESNOTEXIST")
	if a.Error() == nil {
		t.Error("Expected an error, got nil")
	}
	want := a.Error()
	_, got := a.Build()
	if got != want {
		t.Errorf("Build should abort; got: %v, want: %v", got, want)
	}
	b := a.AddFileAttachment("zzzDOESNOTEXIST2")
	got = b.Error()
	if got != want {
		// Only the first error should be stored
		t.Errorf("Error redefined; got %v, wanted %v", got, want)
	}

	a = enmime.Builder().From("name", "from")
	_ = a.AddFileAttachment("zzzDOESNOTEXIST")
	if a.Error() != nil {
		t.Error("AddFileAttachment error mutated receiver")
	}

	a = enmime.Builder().AddFileAttachment("builder_test.go")
	b = enmime.Builder().AddFileAttachment("builder_test.go")
	if a.Error() != nil {
		t.Fatalf("Expected no error, got %v", a.Error())
	}
	if b.Error() != nil {
		t.Fatalf("Expected no error, got %v", b.Error())
	}
	if !a.Equals(b) {
		t.Error("Same AddFileAttachment(value) should be equal")
	}

	a = enmime.Builder().AddFileAttachment("builder_test.go")
	b = enmime.Builder().AddFileAttachment("builder.go")
	if a.Error() != nil {
		t.Fatalf("Expected no error, got %v", a.Error())
	}
	if b.Error() != nil {
		t.Fatalf("Expected no error, got %v", b.Error())
	}
	if a.Equals(b) {
		t.Error("Different AddFileAttachment(value) should not be equal")
	}

	a = enmime.Builder().AddFileAttachment("builder_test.go")
	b = a.AddFileAttachment("builder_test.go")
	b1 := b.AddFileAttachment("builder_test.go")
	b2 := b.AddFileAttachment("builder.go")
	if a.Equals(b) || b.Equals(b1) || b1.Equals(b2) {
		t.Error("AddFileAttachment() should not mutate receiver, failed")
	}

	name := "fake.png"
	ctype := "image/png"
	a = enmime.Builder().
		Text([]byte("text")).
		HTML([]byte("html")).
		From("name", "foo").
		Subject("foo").
		ToAddrs(addrSlice).
		AddFileAttachment(filepath.Join("testdata", "attach", "fake.png"))
	root, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	p := root.DepthMatchFirst(func(p *enmime.Part) bool { return p.FileName == name })
	if p == nil {
		t.Fatalf("Did not find a %q part", name)
	}
	p = root.DepthMatchFirst(func(p *enmime.Part) bool { return p.ContentType == ctype })
	if p == nil {
		t.Fatalf("Did not find a %q part", ctype)
	}
}

func TestBuilderAddInline(t *testing.T) {
	a := enmime.Builder().AddInline([]byte("same"), "ct", "fn", "cid")
	b := enmime.Builder().AddInline([]byte("same"), "ct", "fn", "cid")
	if !a.Equals(b) {
		t.Error("Same AddInline(value) should be equal")
	}

	a = enmime.Builder().AddInline([]byte("foo"), "ct", "fn", "cid")
	b = enmime.Builder().AddInline([]byte("bar"), "ct", "fn", "cid")
	if a.Equals(b) {
		t.Error("Different AddInline(value) should not be equal")
	}

	a = enmime.Builder().AddInline([]byte("foo"), "ct", "fn", "cid")
	b = a.AddInline([]byte("bar"), "ct", "fn", "cid")
	b1 := b.AddInline([]byte("baz"), "ct", "fn", "cid")
	b2 := b.AddInline([]byte("bax"), "ct", "fn", "cid")
	if a.Equals(b) || b.Equals(b1) || b1.Equals(b2) {
		t.Error("AddInline() should not mutate receiver, failed")
	}

	want := "fake JPG data"
	name := "photo.jpg"
	disposition := "inline"
	cid := "<mycid>"
	a = enmime.Builder().
		Text([]byte("text")).
		HTML([]byte("html")).
		From("name", "foo").
		Subject("foo").
		ToAddrs(addrSlice).
		AddInline([]byte(want), "image/jpeg", name, cid)
	root, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	p := root.DepthMatchFirst(func(p *enmime.Part) bool { return p.ContentID == cid })
	if p == nil {
		t.Fatalf("Did not find a %q part", cid)
	}
	if p.Disposition != disposition {
		t.Errorf("Content disposition: %s, want: %s", p.Disposition, disposition)
	}
	got := string(p.Content)
	if got != want {
		t.Errorf("Content: %q, want: %q", got, want)
	}

	// Check structure
	wantTypes := []string{
		"multipart/related",
		"multipart/alternative",
		"text/plain",
		"text/html",
		"image/jpeg",
	}
	gotParts := root.DepthMatchAll(func(p *enmime.Part) bool { return true })
	gotTypes := make([]string, 0)
	for _, p := range gotParts {
		gotTypes = append(gotTypes, p.ContentType)
	}
	test.DiffStrings(t, gotTypes, wantTypes)
}

func TestBuilderAddFileInline(t *testing.T) {
	a := enmime.Builder().AddFileInline("zzzDOESNOTEXIST")
	if a.Error() == nil {
		t.Error("Expected an error, got nil")
	}
	want := a.Error()
	_, got := a.Build()
	if got != want {
		t.Errorf("Build should abort; got: %v, want: %v", got, want)
	}
	b := a.AddFileInline("zzzDOESNOTEXIST2")
	got = b.Error()
	if got != want {
		// Only the first error should be stored
		t.Errorf("Error redefined; got %v, wanted %v", got, want)
	}

	a = enmime.Builder().From("name", "from")
	_ = a.AddFileInline("zzzDOESNOTEXIST")
	if a.Error() != nil {
		t.Error("AddFileInline error mutated receiver")
	}

	a = enmime.Builder().AddFileInline("builder_test.go")
	b = enmime.Builder().AddFileInline("builder_test.go")
	if a.Error() != nil {
		t.Fatalf("Expected no error, got %v", a.Error())
	}
	if b.Error() != nil {
		t.Fatalf("Expected no error, got %v", b.Error())
	}
	if !a.Equals(b) {
		t.Error("Same AddFileInline(value) should be equal")
	}

	a = enmime.Builder().AddFileInline("builder_test.go")
	b = enmime.Builder().AddFileInline("builder.go")
	if a.Error() != nil {
		t.Fatalf("Expected no error, got %v", a.Error())
	}
	if b.Error() != nil {
		t.Fatalf("Expected no error, got %v", b.Error())
	}
	if a.Equals(b) {
		t.Error("Different AddFileInline(value) should not be equal")
	}

	a = enmime.Builder().AddFileInline("builder_test.go")
	b = a.AddFileInline("builder_test.go")
	b1 := b.AddFileInline("builder_test.go")
	b2 := b.AddFileInline("builder.go")
	if a.Equals(b) || b.Equals(b1) || b1.Equals(b2) {
		t.Error("AddFileInline() should not mutate receiver, failed")
	}

	name := "fake.png"
	ctype := "image/png"
	a = enmime.Builder().
		Text([]byte("text")).
		HTML([]byte("html")).
		From("name", "foo").
		Subject("foo").
		ToAddrs(addrSlice).
		AddFileInline(filepath.Join("testdata", "attach", "fake.png"))
	root, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	p := root.DepthMatchFirst(func(p *enmime.Part) bool { return p.ContentID == name })
	if p == nil {
		t.Fatalf("Did not find a %q part", name)
	}
	p = root.DepthMatchFirst(func(p *enmime.Part) bool { return p.ContentType == ctype })
	if p == nil {
		t.Fatalf("Did not find a %q part", ctype)
	}
}

func TestValidation(t *testing.T) {
	_, err := enmime.Builder().
		To("name", "address").
		From("name", "address").
		Subject("subject").
		Build()
	if err != nil {
		t.Errorf("error %v, expected nil", err)
	}

	_, err = enmime.Builder().
		CC("name", "address").
		From("name", "address").
		Subject("subject").
		Build()
	if err != nil {
		t.Errorf("error %v, expected nil", err)
	}

	_, err = enmime.Builder().
		BCC("name", "address").
		From("name", "address").
		Subject("subject").
		Build()
	if err != nil {
		t.Errorf("error %v, expected nil", err)
	}

	_, err = enmime.Builder().
		From("name", "address").
		Subject("subject").
		Build()
	if err == nil {
		t.Error("error nil, expected value")
	}

	_, err = enmime.Builder().
		To("name", "address").
		Subject("subject").
		Build()
	if err == nil {
		t.Error("error nil, expected value")
	}
}

func TestBuilderFullStructure(t *testing.T) {
	a := enmime.Builder().
		Text([]byte("text")).
		HTML([]byte("html")).
		From("name", "foo").
		Subject("foo").
		ToAddrs(addrSlice).
		AddAttachment([]byte("attach data"), "image/jpeg", "image.jpg").
		AddInline([]byte("inline data"), "image/png", "image.png", "")
	root, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}

	want := "1.0"
	got := root.Header.Get("MIME-Version")
	if got != want {
		t.Errorf("MIME-Version: %q, want: %q", got, want)
	}

	// Check structure via "parent > child" content types
	wantTypes := []string{
		" > multipart/mixed",
		"multipart/mixed > multipart/related",
		"multipart/related > multipart/alternative",
		"multipart/alternative > text/plain",
		"multipart/alternative > text/html",
		"multipart/related > image/png",
		"multipart/mixed > image/jpeg",
	}
	gotParts := root.DepthMatchAll(func(p *enmime.Part) bool { return true })
	gotTypes := make([]string, 0)
	for _, p := range gotParts {
		pct := ""
		if p.Parent != nil {
			pct = p.Parent.ContentType
		}
		gotTypes = append(gotTypes, pct+" > "+p.ContentType)
	}
	test.DiffStrings(t, gotTypes, wantTypes)
}

func TestHeader(t *testing.T) {
	a := enmime.Builder().Header("name", "same")
	b := enmime.Builder().Header("name", "same")
	if !a.Equals(b) {
		t.Error("Same Header(value) should be equal")
	}

	a = enmime.Builder().Header("name", "foo")
	b = enmime.Builder().Header("name", "bar")
	if a.Equals(b) {
		t.Error("Different Header(value) should not be equal")
	}

	a = enmime.Builder().Header("name", "foo")
	b = a.Header("name", "bar")
	if a.Equals(b) {
		t.Error("Header() should not mutate receiver, failed")
	}

	want := []string{"value one", "another value"}
	a = enmime.Builder().ToAddrs(addrSlice).From("name", "foo").Subject("foo")
	for _, s := range want {
		a = a.Header("X-Test", s)
	}
	p, err := a.Build()
	if err != nil {
		t.Fatal(err)
	}
	got := p.Header["X-Test"]
	test.DiffStrings(t, got, want)
}

func TestBuilderQPHeaders(t *testing.T) {
	msg := enmime.Builder().
		To("Patrik Fältström", "paf@nada.kth.se").
		To("Keld Jørn Simonsen", "keld@dkuug.dk").
		From("Olle Järnefors", "ojarnef@admin.kth.se").
		Subject("RFC 2047").
		Date(time.Date(2017, 1, 1, 13, 14, 15, 16, time.UTC))
	p, err := msg.Build()
	if err != nil {
		t.Fatal(err)
	}
	b := &bytes.Buffer{}
	p.Encode(b)
	if err != nil {
		t.Fatal(err)
	}

	test.DiffGolden(t, b.Bytes(), "testdata", "encode", "build-qp-addr-headers.golden")
}

func TestSend(t *testing.T) {
	sender := &mockSender{}
	from := "from@example.com"
	tos := []string{"to0@example.com", "to1@example.com"}
	ccs := []string{"cc0@example.com", "cc1@example.com"}
	bccs := []string{"bcc0@example.com", "bcc1@example.com"}
	text := []byte("test text body")
	html := []byte("test html body")
	a := enmime.Builder().
		Text(text).
		HTML(html).
		From("name", from).
		Subject("foo").
		To("to 0", tos[0]).
		To("to 1", tos[1]).
		CC("cc 0", ccs[0]).
		CC("cc 1", ccs[1]).
		BCC("bcc 0", bccs[0]).
		BCC("bcc 1", bccs[1])

	err := a.Send(sender)

	if err != nil {
		t.Fatal(err)
	}
	if sender.from != from {
		t.Errorf("Got from %q, wanted %q", sender.from, from)
	}
	addrs := append([]string{}, tos...)
	addrs = append(addrs, ccs...)
	addrs = append(addrs, bccs...)
	test.DiffStrings(t, sender.to, addrs)
	if !bytes.Contains(sender.msg, text) {
		t.Errorf("msg bytes did not contain text body %q", text)
	}
	if !bytes.Contains(sender.msg, html) {
		t.Errorf("msg bytes did not contain html body %q", html)
	}
}

func TestSendWithReversePath(t *testing.T) {
	sender := &mockSender{}
	ret := "return@example.com"
	from := "from@example.com"
	to := "t0@example.com"
	text := []byte("test text body")
	a := enmime.Builder().
		Text(text).
		From("name", from).
		Subject("foo").
		To("to 0", to)

	err := a.SendWithReversePath(sender, ret)

	if err != nil {
		t.Fatal(err)
	}
	if sender.from != ret {
		// Builder's .From() should not be provided to Sender.Send().
		t.Errorf("Got from %q, wanted %q", sender.from, ret)
	}
	test.DiffStrings(t, sender.to, []string{to})
	if !bytes.Contains(sender.msg, text) {
		t.Errorf("msg bytes did not contain text body %q", text)
	}
}

func TestEmptyTo(t *testing.T) {
	from := "from@example.com"
	text := []byte("test text body")
	rcpt := "rcpt name"
	a := enmime.Builder().
		Text(text).
		From("name", from).
		Subject("foo").
		To(rcpt, "")

	_, err := a.Build()
	if err == nil {
		t.Fatal("Expected error, got nil")
	}

	if err.Error() != enmime.ErrorMissingRecipient {
		t.Fatalf("Unexpected error, wanted %q got %s", enmime.ErrorMissingRecipient, err)
	}
}

func TestEmptyBCC(t *testing.T) {
	from := "from@example.com"
	text := []byte("test text body")
	rcpt := "rcpt name"
	a := enmime.Builder().
		Text(text).
		From("name", from).
		Subject("foo").
		BCC(rcpt, "")

	_, err := a.Build()
	if err == nil {
		t.Fatal("Expected error, got nil")
	}

	if err.Error() != enmime.ErrorMissingRecipient {
		t.Fatalf("Unexpected error, wanted %q got %s", enmime.ErrorMissingRecipient, err)
	}
}

func TestEmptyCC(t *testing.T) {
	from := "from@example.com"
	text := []byte("test text body")
	rcpt := "rcpt name"
	a := enmime.Builder().
		Text(text).
		From("name", from).
		Subject("foo").
		CC(rcpt, "")

	_, err := a.Build()
	if err == nil {
		t.Fatal("Expected error, got nil")
	}

	if err.Error() != enmime.ErrorMissingRecipient {
		t.Fatalf("Unexpected error, wanted %q got %s", enmime.ErrorMissingRecipient, err)
	}
}