diff --git a/vendor/golang.org/x/text/unicode/bidi/bidi.go b/vendor/golang.org/x/text/unicode/bidi/bidi.go
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+++ b/vendor/golang.org/x/text/unicode/bidi/bidi.go
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+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:generate go run gen.go gen_trieval.go gen_ranges.go
+
+// Package bidi contains functionality for bidirectional text support.
+//
+// See https://www.unicode.org/reports/tr9.
+//
+// NOTE: UNDER CONSTRUCTION. This API may change in backwards incompatible ways
+// and without notice.
+package bidi // import "golang.org/x/text/unicode/bidi"
+
+// TODO:
+// The following functionality would not be hard to implement, but hinges on
+// the definition of a Segmenter interface. For now this is up to the user.
+// - Iterate over paragraphs
+// - Segmenter to iterate over runs directly from a given text.
+// Also:
+// - Transformer for reordering?
+// - Transformer (validator, really) for Bidi Rule.
+
+// This API tries to avoid dealing with embedding levels for now. Under the hood
+// these will be computed, but the question is to which extent the user should
+// know they exist. We should at some point allow the user to specify an
+// embedding hierarchy, though.
+
+// A Direction indicates the overall flow of text.
+type Direction int
+
+const (
+	// LeftToRight indicates the text contains no right-to-left characters and
+	// that either there are some left-to-right characters or the option
+	// DefaultDirection(LeftToRight) was passed.
+	LeftToRight Direction = iota
+
+	// RightToLeft indicates the text contains no left-to-right characters and
+	// that either there are some right-to-left characters or the option
+	// DefaultDirection(RightToLeft) was passed.
+	RightToLeft
+
+	// Mixed indicates text contains both left-to-right and right-to-left
+	// characters.
+	Mixed
+
+	// Neutral means that text contains no left-to-right and right-to-left
+	// characters and that no default direction has been set.
+	Neutral
+)
+
+type options struct{}
+
+// An Option is an option for Bidi processing.
+type Option func(*options)
+
+// ICU allows the user to define embedding levels. This may be used, for example,
+// to use hierarchical structure of markup languages to define embeddings.
+// The following option may be a way to expose this functionality in this API.
+// // LevelFunc sets a function that associates nesting levels with the given text.
+// // The levels function will be called with monotonically increasing values for p.
+// func LevelFunc(levels func(p int) int) Option {
+// 	panic("unimplemented")
+// }
+
+// DefaultDirection sets the default direction for a Paragraph. The direction is
+// overridden if the text contains directional characters.
+func DefaultDirection(d Direction) Option {
+	panic("unimplemented")
+}
+
+// A Paragraph holds a single Paragraph for Bidi processing.
+type Paragraph struct {
+	// buffers
+}
+
+// SetBytes configures p for the given paragraph text. It replaces text
+// previously set by SetBytes or SetString. If b contains a paragraph separator
+// it will only process the first paragraph and report the number of bytes
+// consumed from b including this separator. Error may be non-nil if options are
+// given.
+func (p *Paragraph) SetBytes(b []byte, opts ...Option) (n int, err error) {
+	panic("unimplemented")
+}
+
+// SetString configures p for the given paragraph text. It replaces text
+// previously set by SetBytes or SetString. If b contains a paragraph separator
+// it will only process the first paragraph and report the number of bytes
+// consumed from b including this separator. Error may be non-nil if options are
+// given.
+func (p *Paragraph) SetString(s string, opts ...Option) (n int, err error) {
+	panic("unimplemented")
+}
+
+// IsLeftToRight reports whether the principle direction of rendering for this
+// paragraphs is left-to-right. If this returns false, the principle direction
+// of rendering is right-to-left.
+func (p *Paragraph) IsLeftToRight() bool {
+	panic("unimplemented")
+}
+
+// Direction returns the direction of the text of this paragraph.
+//
+// The direction may be LeftToRight, RightToLeft, Mixed, or Neutral.
+func (p *Paragraph) Direction() Direction {
+	panic("unimplemented")
+}
+
+// RunAt reports the Run at the given position of the input text.
+//
+// This method can be used for computing line breaks on paragraphs.
+func (p *Paragraph) RunAt(pos int) Run {
+	panic("unimplemented")
+}
+
+// Order computes the visual ordering of all the runs in a Paragraph.
+func (p *Paragraph) Order() (Ordering, error) {
+	panic("unimplemented")
+}
+
+// Line computes the visual ordering of runs for a single line starting and
+// ending at the given positions in the original text.
+func (p *Paragraph) Line(start, end int) (Ordering, error) {
+	panic("unimplemented")
+}
+
+// An Ordering holds the computed visual order of runs of a Paragraph. Calling
+// SetBytes or SetString on the originating Paragraph invalidates an Ordering.
+// The methods of an Ordering should only be called by one goroutine at a time.
+type Ordering struct{}
+
+// Direction reports the directionality of the runs.
+//
+// The direction may be LeftToRight, RightToLeft, Mixed, or Neutral.
+func (o *Ordering) Direction() Direction {
+	panic("unimplemented")
+}
+
+// NumRuns returns the number of runs.
+func (o *Ordering) NumRuns() int {
+	panic("unimplemented")
+}
+
+// Run returns the ith run within the ordering.
+func (o *Ordering) Run(i int) Run {
+	panic("unimplemented")
+}
+
+// TODO: perhaps with options.
+// // Reorder creates a reader that reads the runes in visual order per character.
+// // Modifiers remain after the runes they modify.
+// func (l *Runs) Reorder() io.Reader {
+// 	panic("unimplemented")
+// }
+
+// A Run is a continuous sequence of characters of a single direction.
+type Run struct {
+}
+
+// String returns the text of the run in its original order.
+func (r *Run) String() string {
+	panic("unimplemented")
+}
+
+// Bytes returns the text of the run in its original order.
+func (r *Run) Bytes() []byte {
+	panic("unimplemented")
+}
+
+// TODO: methods for
+// - Display order
+// - headers and footers
+// - bracket replacement.
+
+// Direction reports the direction of the run.
+func (r *Run) Direction() Direction {
+	panic("unimplemented")
+}
+
+// Position of the Run within the text passed to SetBytes or SetString of the
+// originating Paragraph value.
+func (r *Run) Pos() (start, end int) {
+	panic("unimplemented")
+}
+
+// AppendReverse reverses the order of characters of in, appends them to out,
+// and returns the result. Modifiers will still follow the runes they modify.
+// Brackets are replaced with their counterparts.
+func AppendReverse(out, in []byte) []byte {
+	panic("unimplemented")
+}
+
+// ReverseString reverses the order of characters in s and returns a new string.
+// Modifiers will still follow the runes they modify. Brackets are replaced with
+// their counterparts.
+func ReverseString(s string) string {
+	panic("unimplemented")
+}