format_test.go

package errors

import (
	"errors"
	"fmt"
	"io"
	"regexp"
	"strings"
	"testing"
)

func TestFormatNew(t *testing.T) {
	tests := []struct {
		error
		format string
		want   string
	}{{
		New("error"),
		"%s",
		"error",
	}, {
		New("error"),
		"%v",
		"error",
	}, {
		New("error"),
		"%+v",
		"error\n" +
			"github.com/pkg/errors.TestFormatNew\t.+/github.com/pkg/errors/format_test.go:26",
	}, {
		New("error"),
		"%q",
		`"error"`,
	}}

	for i, tt := range tests {
		testFormatRegexp(t, i, tt.error, tt.format, tt.want)
	}
}

func TestFormatErrorf(t *testing.T) {
	tests := []struct {
		error
		format string
		want   string
	}{{
		Errorf("%s", "error"),
		"%s",
		"error",
	}, {
		Errorf("%s", "error"),
		"%v",
		"error",
	}, {
		Errorf("%s", "error"),
		"%+v",
		"error\n" +
			"github.com/pkg/errors.TestFormatErrorf\t.+/github.com/pkg/errors/format_test.go:55",
	}}

	for i, tt := range tests {
		testFormatRegexp(t, i, tt.error, tt.format, tt.want)
	}
}

func TestFormatWrap(t *testing.T) {
	tests := []struct {
		error
		format string
		want   string
	}{{
		Wrap(New("error"), "error2"),
		"%s",
		"error2: error",
	}, {
		Wrap(New("error"), "error2"),
		"%v",
		"error2: error",
	}, {
		Wrap(New("error"), "error2"),
		"%+v",
		"error\n" +
			"github.com/pkg/errors.TestFormatWrap\t.+/github.com/pkg/errors/format_test.go:80",
	}, {
		Wrap(io.EOF, "error"),
		"%s",
		"error: EOF",
	}, {
		Wrap(io.EOF, "error"),
		"%v",
		"error: EOF",
	}, {
		Wrap(io.EOF, "error"),
		"%+v",
		"EOF\n" +
			"error\n" +
			"github.com/pkg/errors.TestFormatWrap\t.+/github.com/pkg/errors/format_test.go:93",
	}, {
		Wrap(Wrap(io.EOF, "error1"), "error2"),
		"%+v",
		"EOF\n" +
			"error1\n" +
			"github.com/pkg/errors.TestFormatWrap\t.+/github.com/pkg/errors/format_test.go:99\n",
	}, {
		Wrap(New("error with space"), "context"),
		"%q",
		`"context: error with space"`,
	}}

	for i, tt := range tests {
		testFormatRegexp(t, i, tt.error, tt.format, tt.want)
	}
}

func TestFormatWrapf(t *testing.T) {
	tests := []struct {
		error
		format string
		want   string
	}{{
		Wrapf(io.EOF, "error%d", 2),
		"%s",
		"error2: EOF",
	}, {
		Wrapf(io.EOF, "error%d", 2),
		"%v",
		"error2: EOF",
	}, {
		Wrapf(io.EOF, "error%d", 2),
		"%+v",
		"EOF\n" +
			"error2\n" +
			"github.com/pkg/errors.TestFormatWrapf\t.+/github.com/pkg/errors/format_test.go:129",
	}, {
		Wrapf(New("error"), "error%d", 2),
		"%s",
		"error2: error",
	}, {
		Wrapf(New("error"), "error%d", 2),
		"%v",
		"error2: error",
	}, {
		Wrapf(New("error"), "error%d", 2),
		"%+v",
		"error\n" +
			"github.com/pkg/errors.TestFormatWrapf\t.+/github.com/pkg/errors/format_test.go:143",
	}}

	for i, tt := range tests {
		testFormatRegexp(t, i, tt.error, tt.format, tt.want)
	}
}

func TestFormatWithStack(t *testing.T) {
	tests := []struct {
		error
		format string
		want   []string
	}{{
		WithStack(io.EOF),
		"%s",
		[]string{"EOF"},
	}, {
		WithStack(io.EOF),
		"%v",
		[]string{"EOF"},
	}, {
		WithStack(io.EOF),
		"%+v",
		[]string{"EOF",
			"github.com/pkg/errors.TestFormatWithStack\t.+/github.com/pkg/errors/format_test.go:168"},
	}, {
		WithStack(New("error")),
		"%s",
		[]string{"error"},
	}, {
		WithStack(New("error")),
		"%v",
		[]string{"error"},
	}, {
		WithStack(New("error")),
		"%+v",
		[]string{"error",
			"github.com/pkg/errors.TestFormatWithStack\t.+/github.com/pkg/errors/format_test.go:181",
			"github.com/pkg/errors.TestFormatWithStack\t.+/github.com/pkg/errors/format_test.go:181"},
	}, {
		WithStack(WithStack(io.EOF)),
		"%+v",
		[]string{"EOF",
			"github.com/pkg/errors.TestFormatWithStack\t.+/github.com/pkg/errors/format_test.go:187",
			"github.com/pkg/errors.TestFormatWithStack\t.+/github.com/pkg/errors/format_test.go:187"},
	}, {
		WithStack(WithStack(Wrapf(io.EOF, "message"))),
		"%+v",
		[]string{"EOF",
			"message",
			"github.com/pkg/errors.TestFormatWithStack\t.+/github.com/pkg/errors/format_test.go:193",
			"github.com/pkg/errors.TestFormatWithStack\t.+/github.com/pkg/errors/format_test.go:193",
			"github.com/pkg/errors.TestFormatWithStack\t.+/github.com/pkg/errors/format_test.go:193"},
	}, {
		WithStack(Errorf("error%d", 1)),
		"%+v",
		[]string{"error1",
			"github.com/pkg/errors.TestFormatWithStack\t.+/github.com/pkg/errors/format_test.go:201",
			"github.com/pkg/errors.TestFormatWithStack\t.+/github.com/pkg/errors/format_test.go:201"},
	}}

	for i, tt := range tests {
		testFormatCompleteCompare(t, i, tt.error, tt.format, tt.want, true)
	}
}

func TestFormatWithMessage(t *testing.T) {
	tests := []struct {
		error
		format string
		want   []string
	}{{
		WithMessage(New("error"), "error2"),
		"%s",
		[]string{"error2: error"},
	}, {
		WithMessage(New("error"), "error2"),
		"%v",
		[]string{"error2: error"},
	}, {
		WithMessage(New("error"), "error2"),
		"%+v",
		[]string{
			"error",
			"github.com/pkg/errors.TestFormatWithMessage\t.+/github.com/pkg/errors/format_test.go:227",
			"error2"},
	}, {
		WithMessage(io.EOF, "addition1"),
		"%s",
		[]string{"addition1: EOF"},
	}, {
		WithMessage(io.EOF, "addition1"),
		"%v",
		[]string{"addition1: EOF"},
	}, {
		WithMessage(io.EOF, "addition1"),
		"%+v",
		[]string{"EOF", "addition1"},
	}, {
		WithMessage(WithMessage(io.EOF, "addition1"), "addition2"),
		"%v",
		[]string{"addition2: addition1: EOF"},
	}, {
		WithMessage(WithMessage(io.EOF, "addition1"), "addition2"),
		"%+v",
		[]string{"EOF", "addition1", "addition2"},
	}, {
		Wrap(WithMessage(io.EOF, "error1"), "error2"),
		"%+v",
		[]string{"EOF", "error1", "error2",
			"github.com/pkg/errors.TestFormatWithMessage\t.+/github.com/pkg/errors/format_test.go:254"},
	}, {
		WithMessage(Errorf("error%d", 1), "error2"),
		"%+v",
		[]string{"error1",
			"github.com/pkg/errors.TestFormatWithMessage\t.+/github.com/pkg/errors/format_test.go:259",
			"error2"},
	}, {
		WithMessage(WithStack(io.EOF), "error"),
		"%+v",
		[]string{
			"EOF",
			"github.com/pkg/errors.TestFormatWithMessage\t.+/github.com/pkg/errors/format_test.go:265",
			"error"},
	}, {
		WithMessage(Wrap(WithStack(io.EOF), "inside-error"), "outside-error"),
		"%+v",
		[]string{
			"EOF",
			"github.com/pkg/errors.TestFormatWithMessage\t.+/github.com/pkg/errors/format_test.go:272",
			"inside-error",
			"github.com/pkg/errors.TestFormatWithMessage\t.+/github.com/pkg/errors/format_test.go:272",
			"outside-error"},
	}}

	for i, tt := range tests {
		testFormatCompleteCompare(t, i, tt.error, tt.format, tt.want, true)
	}
}

func TestFormatGeneric(t *testing.T) {
	starts := []struct {
		err  error
		want []string
	}{
		{New("new-error"), []string{
			"new-error",
			"github.com/pkg/errors.TestFormatGeneric\t.+/github.com/pkg/errors/format_test.go:292"},
		}, {Errorf("errorf-error"), []string{
			"errorf-error",
			"github.com/pkg/errors.TestFormatGeneric\t.+/github.com/pkg/errors/format_test.go:295"},
		}, {errors.New("errors-new-error"), []string{
			"errors-new-error"},
		},
	}

	wrappers := []wrapper{
		{
			func(err error) error { return WithMessage(err, "with-message") },
			[]string{"with-message"},
		}, {
			func(err error) error { return WithStack(err) },
			[]string{
				"github.com/pkg/errors.TestFormatGeneric.func2\t.+/github.com/pkg/errors/format_test.go:308",
			},
		}, {
			func(err error) error { return Wrap(err, "wrap-error") },
			[]string{
				"wrap-error",
				"github.com/pkg/errors.(func·003|TestFormatGeneric.func3)\t.+/github.com/pkg/errors/format_test.go:313",
			},
		}, {
			func(err error) error { return Wrapf(err, "wrapf-error%d", 1) },
			[]string{
				"wrapf-error1",
				"github.com/pkg/errors.(func·004|TestFormatGeneric.func4)\t.+/github.com/pkg/errors/format_test.go:319",
			},
		},
	}

	for s := range starts {
		err := starts[s].err
		want := starts[s].want
		testFormatCompleteCompare(t, s, err, "%+v", want, false)
		testGenericRecursive(t, err, want, wrappers, 3)
	}
}

func wrappedNew(message string) error { // This function will be mid-stack inlined in go 1.12+
	return New(message)
}

func TestFormatWrappedNew(t *testing.T) {
	tests := []struct {
		error
		format string
		want   string
	}{{
		wrappedNew("error"),
		"%+v",
		"error\n" +
			"github.com/pkg/errors.wrappedNew\t.+/github.com/pkg/errors/format_test.go:336",
	}}

	for i, tt := range tests {
		testFormatRegexp(t, i, tt.error, tt.format, tt.want)
	}
}

func testFormatRegexp(t *testing.T, n int, arg interface{}, format, want string) {
	t.Helper()
	got := fmt.Sprintf(format, arg)
	gotLines := strings.SplitN(got, "\n", -1)
	wantLines := strings.SplitN(want, "\n", -1)

	if len(wantLines) > len(gotLines) {
		t.Errorf("test %d: wantLines(%d) > gotLines(%d):\n got: %q\nwant: %q", n+1, len(wantLines), len(gotLines), got, want)
		return
	}

	for i, w := range wantLines {
		match, err := regexp.MatchString(w, gotLines[i])
		if err != nil {
			t.Fatal(err)
		}
		if !match {
			t.Errorf("test %d: line %d: fmt.Sprintf(%q, err):\n got: %q\nwant: %q", n+1, i+1, format, got, want)
		}
	}
}

var stackLineR = regexp.MustCompile(`\.`)

// parseBlocks parses input into a slice, where:
//   - incase entry contains a newline, its a stacktrace
//   - incase entry contains no newline, its a solo line.
//
// Detecting stack boundaries only works incase the WithStack-calls are
// to be found on the same line, thats why it is optionally here.
//
// Example use:
//
//	for _, e := range blocks {
//	  if strings.ContainsAny(e, "\n") {
//	    // Match as stack
//	  } else {
//	    // Match as line
//	  }
//	}
func parseBlocks(input string, detectStackboundaries bool) ([]string, error) {
	return strings.Split(input, "\n"), nil
}

func testFormatCompleteCompare(t *testing.T, n int, arg interface{}, format string, want []string, detectStackBoundaries bool) {
	gotStr := fmt.Sprintf(format, arg)

	got, err := parseBlocks(gotStr, detectStackBoundaries)
	if err != nil {
		t.Fatal(err)
	}

	if len(got) != len(want) {
		t.Fatalf("test %d: fmt.Sprintf(%s, err) -> wrong number of blocks: got(%d) want(%d)\n got: %s\nwant: %s\ngotStr: %q",
			n+1, format, len(got), len(want), prettyBlocks(got), prettyBlocks(want), gotStr)
	}

	for i := range got {
		if strings.ContainsAny(want[i], "\t\n.+") {
			// Match as stack
			match, err := regexp.MatchString(want[i], got[i])
			if err != nil {
				t.Fatal(err)
			}
			if !match {
				t.Fatalf("test %d: block %d: fmt.Sprintf(%q, err):\ngot:\n%q\nwant:\n%q\nall-got:\n%s\nall-want:\n%s\n",
					n+1, i+1, format, got[i], want[i], prettyBlocks(got), prettyBlocks(want))
			}
		} else {
			// Match as message
			if got[i] != want[i] {
				t.Fatalf("test %d: fmt.Sprintf(%s, err) at block %d got != want:\n got: %q\nwant: %q", n+1, format, i+1, got[i], want[i])
			}
		}
	}
}

type wrapper struct {
	wrap func(err error) error
	want []string
}

func prettyBlocks(blocks []string) string {
	var out []string

	for _, b := range blocks {
		out = append(out, fmt.Sprintf("%v", b))
	}

	return "   " + strings.Join(out, "\n   ")
}

func testGenericRecursive(t *testing.T, beforeErr error, beforeWant []string, list []wrapper, maxDepth int) {
	if len(beforeWant) == 0 {
		panic("beforeWant must not be empty")
	}
	for _, w := range list {
		if len(w.want) == 0 {
			panic("want must not be empty")
		}

		err := w.wrap(beforeErr)

		// Copy required cause append(beforeWant, ..) modified beforeWant subtly.
		beforeCopy := make([]string, len(beforeWant))
		copy(beforeCopy, beforeWant)

		beforeWant := beforeCopy
		last := len(beforeWant) - 1
		var want []string

		// Merge two stacks behind each other.
		if strings.ContainsAny(beforeWant[last], "\n") && strings.ContainsAny(w.want[0], "\n") {
			want = append(beforeWant[:last], append([]string{beforeWant[last] + "((?s).*)" + w.want[0]}, w.want[1:]...)...)
		} else {
			want = append(beforeWant, w.want...)
		}

		testFormatCompleteCompare(t, maxDepth, err, "%+v", want, false)
		if maxDepth > 0 {
			testGenericRecursive(t, err, want, list, maxDepth-1)
		}
	}
}

func TestFormatWithDetails(t *testing.T) {
	tests := []struct {
		err    error
		format string
		want   string
	}{
		{WithDetails(nil), "%s", ""},
		{WithDetails(nil), "%v", ""},
		{WithDetails(nil), "%+v", ""},
		{WithDetails(io.EOF, "whoops"), "%s", "EOF"},
		{WithDetails(io.EOF, "whoops"), "%v", "EOF"},
		{WithDetails(io.EOF, "whoops"), "%+v", "EOF"},
		{WithDetails(Wrap(io.EOF, "read error"), "whoops", 1, 2.2), "%s", "read error: EOF"},
		{WithDetails(Wrap(io.EOF, "read error"), "whoops", 1, 2.2), "%v", "read error: EOF"},
		{WithDetails(Wrap(io.EOF, "read error"), "whoops", 1, 2.2), "%+v", "EOF\nread error\n" +
			"github.com/pkg/errors.TestFormatWithDetails\t.+/github.com/pkg/errors/format_test.go:495",
		},
	}

	for i, tt := range tests {
		testFormatRegexp(t, i, tt.err, tt.format, tt.want)
	}
}