Switch to Go modules and make other changes

1 files changed, 0 insertions, 772 deletions

diff --git a/vendor/github.com/pmezard/go-difflib/difflib/difflib.go b/vendor/github.com/pmezard/go-difflib/difflib/difflib.go
deleted file mode 100644
index 003e99f..0000000
--- a/vendor/github.com/pmezard/go-difflib/difflib/difflib.go
+++ /dev/null
@@ -1,772 +0,0 @@
-// Package difflib is a partial port of Python difflib module.
-//
-// It provides tools to compare sequences of strings and generate textual diffs.
-//
-// The following class and functions have been ported:
-//
-// - SequenceMatcher
-//
-// - unified_diff
-//
-// - context_diff
-//
-// Getting unified diffs was the main goal of the port. Keep in mind this code
-// is mostly suitable to output text differences in a human friendly way, there
-// are no guarantees generated diffs are consumable by patch(1).
-package difflib
-
-import (
-	"bufio"
-	"bytes"
-	"fmt"
-	"io"
-	"strings"
-)
-
-func min(a, b int) int {
-	if a < b {
-		return a
-	}
-	return b
-}
-
-func max(a, b int) int {
-	if a > b {
-		return a
-	}
-	return b
-}
-
-func calculateRatio(matches, length int) float64 {
-	if length > 0 {
-		return 2.0 * float64(matches) / float64(length)
-	}
-	return 1.0
-}
-
-type Match struct {
-	A    int
-	B    int
-	Size int
-}
-
-type OpCode struct {
-	Tag byte
-	I1  int
-	I2  int
-	J1  int
-	J2  int
-}
-
-// SequenceMatcher compares sequence of strings. The basic
-// algorithm predates, and is a little fancier than, an algorithm
-// published in the late 1980's by Ratcliff and Obershelp under the
-// hyperbolic name "gestalt pattern matching".  The basic idea is to find
-// the longest contiguous matching subsequence that contains no "junk"
-// elements (R-O doesn't address junk).  The same idea is then applied
-// recursively to the pieces of the sequences to the left and to the right
-// of the matching subsequence.  This does not yield minimal edit
-// sequences, but does tend to yield matches that "look right" to people.
-//
-// SequenceMatcher tries to compute a "human-friendly diff" between two
-// sequences.  Unlike e.g. UNIX(tm) diff, the fundamental notion is the
-// longest *contiguous* & junk-free matching subsequence.  That's what
-// catches peoples' eyes.  The Windows(tm) windiff has another interesting
-// notion, pairing up elements that appear uniquely in each sequence.
-// That, and the method here, appear to yield more intuitive difference
-// reports than does diff.  This method appears to be the least vulnerable
-// to synching up on blocks of "junk lines", though (like blank lines in
-// ordinary text files, or maybe "<P>" lines in HTML files).  That may be
-// because this is the only method of the 3 that has a *concept* of
-// "junk" <wink>.
-//
-// Timing:  Basic R-O is cubic time worst case and quadratic time expected
-// case.  SequenceMatcher is quadratic time for the worst case and has
-// expected-case behavior dependent in a complicated way on how many
-// elements the sequences have in common; best case time is linear.
-type SequenceMatcher struct {
-	a              []string
-	b              []string
-	b2j            map[string][]int
-	IsJunk         func(string) bool
-	autoJunk       bool
-	bJunk          map[string]struct{}
-	matchingBlocks []Match
-	fullBCount     map[string]int
-	bPopular       map[string]struct{}
-	opCodes        []OpCode
-}
-
-func NewMatcher(a, b []string) *SequenceMatcher {
-	m := SequenceMatcher{autoJunk: true}
-	m.SetSeqs(a, b)
-	return &m
-}
-
-func NewMatcherWithJunk(a, b []string, autoJunk bool,
-	isJunk func(string) bool) *SequenceMatcher {
-
-	m := SequenceMatcher{IsJunk: isJunk, autoJunk: autoJunk}
-	m.SetSeqs(a, b)
-	return &m
-}
-
-// Set two sequences to be compared.
-func (m *SequenceMatcher) SetSeqs(a, b []string) {
-	m.SetSeq1(a)
-	m.SetSeq2(b)
-}
-
-// Set the first sequence to be compared. The second sequence to be compared is
-// not changed.
-//
-// SequenceMatcher computes and caches detailed information about the second
-// sequence, so if you want to compare one sequence S against many sequences,
-// use .SetSeq2(s) once and call .SetSeq1(x) repeatedly for each of the other
-// sequences.
-//
-// See also SetSeqs() and SetSeq2().
-func (m *SequenceMatcher) SetSeq1(a []string) {
-	if &a == &m.a {
-		return
-	}
-	m.a = a
-	m.matchingBlocks = nil
-	m.opCodes = nil
-}
-
-// Set the second sequence to be compared. The first sequence to be compared is
-// not changed.
-func (m *SequenceMatcher) SetSeq2(b []string) {
-	if &b == &m.b {
-		return
-	}
-	m.b = b
-	m.matchingBlocks = nil
-	m.opCodes = nil
-	m.fullBCount = nil
-	m.chainB()
-}
-
-func (m *SequenceMatcher) chainB() {
-	// Populate line -> index mapping
-	b2j := map[string][]int{}
-	for i, s := range m.b {
-		indices := b2j[s]
-		indices = append(indices, i)
-		b2j[s] = indices
-	}
-
-	// Purge junk elements
-	m.bJunk = map[string]struct{}{}
-	if m.IsJunk != nil {
-		junk := m.bJunk
-		for s, _ := range b2j {
-			if m.IsJunk(s) {
-				junk[s] = struct{}{}
-			}
-		}
-		for s, _ := range junk {
-			delete(b2j, s)
-		}
-	}
-
-	// Purge remaining popular elements
-	popular := map[string]struct{}{}
-	n := len(m.b)
-	if m.autoJunk && n >= 200 {
-		ntest := n/100 + 1
-		for s, indices := range b2j {
-			if len(indices) > ntest {
-				popular[s] = struct{}{}
-			}
-		}
-		for s, _ := range popular {
-			delete(b2j, s)
-		}
-	}
-	m.bPopular = popular
-	m.b2j = b2j
-}
-
-func (m *SequenceMatcher) isBJunk(s string) bool {
-	_, ok := m.bJunk[s]
-	return ok
-}
-
-// Find longest matching block in a[alo:ahi] and b[blo:bhi].
-//
-// If IsJunk is not defined:
-//
-// Return (i,j,k) such that a[i:i+k] is equal to b[j:j+k], where
-//     alo <= i <= i+k <= ahi
-//     blo <= j <= j+k <= bhi
-// and for all (i',j',k') meeting those conditions,
-//     k >= k'
-//     i <= i'
-//     and if i == i', j <= j'
-//
-// In other words, of all maximal matching blocks, return one that
-// starts earliest in a, and of all those maximal matching blocks that
-// start earliest in a, return the one that starts earliest in b.
-//
-// If IsJunk is defined, first the longest matching block is
-// determined as above, but with the additional restriction that no
-// junk element appears in the block.  Then that block is extended as
-// far as possible by matching (only) junk elements on both sides.  So
-// the resulting block never matches on junk except as identical junk
-// happens to be adjacent to an "interesting" match.
-//
-// If no blocks match, return (alo, blo, 0).
-func (m *SequenceMatcher) findLongestMatch(alo, ahi, blo, bhi int) Match {
-	// CAUTION:  stripping common prefix or suffix would be incorrect.
-	// E.g.,
-	//    ab
-	//    acab
-	// Longest matching block is "ab", but if common prefix is
-	// stripped, it's "a" (tied with "b").  UNIX(tm) diff does so
-	// strip, so ends up claiming that ab is changed to acab by
-	// inserting "ca" in the middle.  That's minimal but unintuitive:
-	// "it's obvious" that someone inserted "ac" at the front.
-	// Windiff ends up at the same place as diff, but by pairing up
-	// the unique 'b's and then matching the first two 'a's.
-	besti, bestj, bestsize := alo, blo, 0
-
-	// find longest junk-free match
-	// during an iteration of the loop, j2len[j] = length of longest
-	// junk-free match ending with a[i-1] and b[j]
-	j2len := map[int]int{}
-	for i := alo; i != ahi; i++ {
-		// look at all instances of a[i] in b; note that because
-		// b2j has no junk keys, the loop is skipped if a[i] is junk
-		newj2len := map[int]int{}
-		for _, j := range m.b2j[m.a[i]] {
-			// a[i] matches b[j]
-			if j < blo {
-				continue
-			}
-			if j >= bhi {
-				break
-			}
-			k := j2len[j-1] + 1
-			newj2len[j] = k
-			if k > bestsize {
-				besti, bestj, bestsize = i-k+1, j-k+1, k
-			}
-		}
-		j2len = newj2len
-	}
-
-	// Extend the best by non-junk elements on each end.  In particular,
-	// "popular" non-junk elements aren't in b2j, which greatly speeds
-	// the inner loop above, but also means "the best" match so far
-	// doesn't contain any junk *or* popular non-junk elements.
-	for besti > alo && bestj > blo && !m.isBJunk(m.b[bestj-1]) &&
-		m.a[besti-1] == m.b[bestj-1] {
-		besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
-	}
-	for besti+bestsize < ahi && bestj+bestsize < bhi &&
-		!m.isBJunk(m.b[bestj+bestsize]) &&
-		m.a[besti+bestsize] == m.b[bestj+bestsize] {
-		bestsize += 1
-	}
-
-	// Now that we have a wholly interesting match (albeit possibly
-	// empty!), we may as well suck up the matching junk on each
-	// side of it too.  Can't think of a good reason not to, and it
-	// saves post-processing the (possibly considerable) expense of
-	// figuring out what to do with it.  In the case of an empty
-	// interesting match, this is clearly the right thing to do,
-	// because no other kind of match is possible in the regions.
-	for besti > alo && bestj > blo && m.isBJunk(m.b[bestj-1]) &&
-		m.a[besti-1] == m.b[bestj-1] {
-		besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
-	}
-	for besti+bestsize < ahi && bestj+bestsize < bhi &&
-		m.isBJunk(m.b[bestj+bestsize]) &&
-		m.a[besti+bestsize] == m.b[bestj+bestsize] {
-		bestsize += 1
-	}
-
-	return Match{A: besti, B: bestj, Size: bestsize}
-}
-
-// Return list of triples describing matching subsequences.
-//
-// Each triple is of the form (i, j, n), and means that
-// a[i:i+n] == b[j:j+n].  The triples are monotonically increasing in
-// i and in j. It's also guaranteed that if (i, j, n) and (i', j', n') are
-// adjacent triples in the list, and the second is not the last triple in the
-// list, then i+n != i' or j+n != j'. IOW, adjacent triples never describe
-// adjacent equal blocks.
-//
-// The last triple is a dummy, (len(a), len(b), 0), and is the only
-// triple with n==0.
-func (m *SequenceMatcher) GetMatchingBlocks() []Match {
-	if m.matchingBlocks != nil {
-		return m.matchingBlocks
-	}
-
-	var matchBlocks func(alo, ahi, blo, bhi int, matched []Match) []Match
-	matchBlocks = func(alo, ahi, blo, bhi int, matched []Match) []Match {
-		match := m.findLongestMatch(alo, ahi, blo, bhi)
-		i, j, k := match.A, match.B, match.Size
-		if match.Size > 0 {
-			if alo < i && blo < j {
-				matched = matchBlocks(alo, i, blo, j, matched)
-			}
-			matched = append(matched, match)
-			if i+k < ahi && j+k < bhi {
-				matched = matchBlocks(i+k, ahi, j+k, bhi, matched)
-			}
-		}
-		return matched
-	}
-	matched := matchBlocks(0, len(m.a), 0, len(m.b), nil)
-
-	// It's possible that we have adjacent equal blocks in the
-	// matching_blocks list now.
-	nonAdjacent := []Match{}
-	i1, j1, k1 := 0, 0, 0
-	for _, b := range matched {
-		// Is this block adjacent to i1, j1, k1?
-		i2, j2, k2 := b.A, b.B, b.Size
-		if i1+k1 == i2 && j1+k1 == j2 {
-			// Yes, so collapse them -- this just increases the length of
-			// the first block by the length of the second, and the first
-			// block so lengthened remains the block to compare against.
-			k1 += k2
-		} else {
-			// Not adjacent.  Remember the first block (k1==0 means it's
-			// the dummy we started with), and make the second block the
-			// new block to compare against.
-			if k1 > 0 {
-				nonAdjacent = append(nonAdjacent, Match{i1, j1, k1})
-			}
-			i1, j1, k1 = i2, j2, k2
-		}
-	}
-	if k1 > 0 {
-		nonAdjacent = append(nonAdjacent, Match{i1, j1, k1})
-	}
-
-	nonAdjacent = append(nonAdjacent, Match{len(m.a), len(m.b), 0})
-	m.matchingBlocks = nonAdjacent
-	return m.matchingBlocks
-}
-
-// Return list of 5-tuples describing how to turn a into b.
-//
-// Each tuple is of the form (tag, i1, i2, j1, j2).  The first tuple
-// has i1 == j1 == 0, and remaining tuples have i1 == the i2 from the
-// tuple preceding it, and likewise for j1 == the previous j2.
-//
-// The tags are characters, with these meanings:
-//
-// 'r' (replace):  a[i1:i2] should be replaced by b[j1:j2]
-//
-// 'd' (delete):   a[i1:i2] should be deleted, j1==j2 in this case.
-//
-// 'i' (insert):   b[j1:j2] should be inserted at a[i1:i1], i1==i2 in this case.
-//
-// 'e' (equal):    a[i1:i2] == b[j1:j2]
-func (m *SequenceMatcher) GetOpCodes() []OpCode {
-	if m.opCodes != nil {
-		return m.opCodes
-	}
-	i, j := 0, 0
-	matching := m.GetMatchingBlocks()
-	opCodes := make([]OpCode, 0, len(matching))
-	for _, m := range matching {
-		//  invariant:  we've pumped out correct diffs to change
-		//  a[:i] into b[:j], and the next matching block is
-		//  a[ai:ai+size] == b[bj:bj+size]. So we need to pump
-		//  out a diff to change a[i:ai] into b[j:bj], pump out
-		//  the matching block, and move (i,j) beyond the match
-		ai, bj, size := m.A, m.B, m.Size
-		tag := byte(0)
-		if i < ai && j < bj {
-			tag = 'r'
-		} else if i < ai {
-			tag = 'd'
-		} else if j < bj {
-			tag = 'i'
-		}
-		if tag > 0 {
-			opCodes = append(opCodes, OpCode{tag, i, ai, j, bj})
-		}
-		i, j = ai+size, bj+size
-		// the list of matching blocks is terminated by a
-		// sentinel with size 0
-		if size > 0 {
-			opCodes = append(opCodes, OpCode{'e', ai, i, bj, j})
-		}
-	}
-	m.opCodes = opCodes
-	return m.opCodes
-}
-
-// Isolate change clusters by eliminating ranges with no changes.
-//
-// Return a generator of groups with up to n lines of context.
-// Each group is in the same format as returned by GetOpCodes().
-func (m *SequenceMatcher) GetGroupedOpCodes(n int) [][]OpCode {
-	if n < 0 {
-		n = 3
-	}
-	codes := m.GetOpCodes()
-	if len(codes) == 0 {
-		codes = []OpCode{OpCode{'e', 0, 1, 0, 1}}
-	}
-	// Fixup leading and trailing groups if they show no changes.
-	if codes[0].Tag == 'e' {
-		c := codes[0]
-		i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
-		codes[0] = OpCode{c.Tag, max(i1, i2-n), i2, max(j1, j2-n), j2}
-	}
-	if codes[len(codes)-1].Tag == 'e' {
-		c := codes[len(codes)-1]
-		i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
-		codes[len(codes)-1] = OpCode{c.Tag, i1, min(i2, i1+n), j1, min(j2, j1+n)}
-	}
-	nn := n + n
-	groups := [][]OpCode{}
-	group := []OpCode{}
-	for _, c := range codes {
-		i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
-		// End the current group and start a new one whenever
-		// there is a large range with no changes.
-		if c.Tag == 'e' && i2-i1 > nn {
-			group = append(group, OpCode{c.Tag, i1, min(i2, i1+n),
-				j1, min(j2, j1+n)})
-			groups = append(groups, group)
-			group = []OpCode{}
-			i1, j1 = max(i1, i2-n), max(j1, j2-n)
-		}
-		group = append(group, OpCode{c.Tag, i1, i2, j1, j2})
-	}
-	if len(group) > 0 && !(len(group) == 1 && group[0].Tag == 'e') {
-		groups = append(groups, group)
-	}
-	return groups
-}
-
-// Return a measure of the sequences' similarity (float in [0,1]).
-//
-// Where T is the total number of elements in both sequences, and
-// M is the number of matches, this is 2.0*M / T.
-// Note that this is 1 if the sequences are identical, and 0 if
-// they have nothing in common.
-//
-// .Ratio() is expensive to compute if you haven't already computed
-// .GetMatchingBlocks() or .GetOpCodes(), in which case you may
-// want to try .QuickRatio() or .RealQuickRation() first to get an
-// upper bound.
-func (m *SequenceMatcher) Ratio() float64 {
-	matches := 0
-	for _, m := range m.GetMatchingBlocks() {
-		matches += m.Size
-	}
-	return calculateRatio(matches, len(m.a)+len(m.b))
-}
-
-// Return an upper bound on ratio() relatively quickly.
-//
-// This isn't defined beyond that it is an upper bound on .Ratio(), and
-// is faster to compute.
-func (m *SequenceMatcher) QuickRatio() float64 {
-	// viewing a and b as multisets, set matches to the cardinality
-	// of their intersection; this counts the number of matches
-	// without regard to order, so is clearly an upper bound
-	if m.fullBCount == nil {
-		m.fullBCount = map[string]int{}
-		for _, s := range m.b {
-			m.fullBCount[s] = m.fullBCount[s] + 1
-		}
-	}
-
-	// avail[x] is the number of times x appears in 'b' less the
-	// number of times we've seen it in 'a' so far ... kinda
-	avail := map[string]int{}
-	matches := 0
-	for _, s := range m.a {
-		n, ok := avail[s]
-		if !ok {
-			n = m.fullBCount[s]
-		}
-		avail[s] = n - 1
-		if n > 0 {
-			matches += 1
-		}
-	}
-	return calculateRatio(matches, len(m.a)+len(m.b))
-}
-
-// Return an upper bound on ratio() very quickly.
-//
-// This isn't defined beyond that it is an upper bound on .Ratio(), and
-// is faster to compute than either .Ratio() or .QuickRatio().
-func (m *SequenceMatcher) RealQuickRatio() float64 {
-	la, lb := len(m.a), len(m.b)
-	return calculateRatio(min(la, lb), la+lb)
-}
-
-// Convert range to the "ed" format
-func formatRangeUnified(start, stop int) string {
-	// Per the diff spec at http://www.unix.org/single_unix_specification/
-	beginning := start + 1 // lines start numbering with one
-	length := stop - start
-	if length == 1 {
-		return fmt.Sprintf("%d", beginning)
-	}
-	if length == 0 {
-		beginning -= 1 // empty ranges begin at line just before the range
-	}
-	return fmt.Sprintf("%d,%d", beginning, length)
-}
-
-// Unified diff parameters
-type UnifiedDiff struct {
-	A        []string // First sequence lines
-	FromFile string   // First file name
-	FromDate string   // First file time
-	B        []string // Second sequence lines
-	ToFile   string   // Second file name
-	ToDate   string   // Second file time
-	Eol      string   // Headers end of line, defaults to LF
-	Context  int      // Number of context lines
-}
-
-// Compare two sequences of lines; generate the delta as a unified diff.
-//
-// Unified diffs are a compact way of showing line changes and a few
-// lines of context.  The number of context lines is set by 'n' which
-// defaults to three.
-//
-// By default, the diff control lines (those with ---, +++, or @@) are
-// created with a trailing newline.  This is helpful so that inputs
-// created from file.readlines() result in diffs that are suitable for
-// file.writelines() since both the inputs and outputs have trailing
-// newlines.
-//
-// For inputs that do not have trailing newlines, set the lineterm
-// argument to "" so that the output will be uniformly newline free.
-//
-// The unidiff format normally has a header for filenames and modification
-// times.  Any or all of these may be specified using strings for
-// 'fromfile', 'tofile', 'fromfiledate', and 'tofiledate'.
-// The modification times are normally expressed in the ISO 8601 format.
-func WriteUnifiedDiff(writer io.Writer, diff UnifiedDiff) error {
-	buf := bufio.NewWriter(writer)
-	defer buf.Flush()
-	wf := func(format string, args ...interface{}) error {
-		_, err := buf.WriteString(fmt.Sprintf(format, args...))
-		return err
-	}
-	ws := func(s string) error {
-		_, err := buf.WriteString(s)
-		return err
-	}
-
-	if len(diff.Eol) == 0 {
-		diff.Eol = "\n"
-	}
-
-	started := false
-	m := NewMatcher(diff.A, diff.B)
-	for _, g := range m.GetGroupedOpCodes(diff.Context) {
-		if !started {
-			started = true
-			fromDate := ""
-			if len(diff.FromDate) > 0 {
-				fromDate = "\t" + diff.FromDate
-			}
-			toDate := ""
-			if len(diff.ToDate) > 0 {
-				toDate = "\t" + diff.ToDate
-			}
-			if diff.FromFile != "" || diff.ToFile != "" {
-				err := wf("--- %s%s%s", diff.FromFile, fromDate, diff.Eol)
-				if err != nil {
-					return err
-				}
-				err = wf("+++ %s%s%s", diff.ToFile, toDate, diff.Eol)
-				if err != nil {
-					return err
-				}
-			}
-		}
-		first, last := g[0], g[len(g)-1]
-		range1 := formatRangeUnified(first.I1, last.I2)
-		range2 := formatRangeUnified(first.J1, last.J2)
-		if err := wf("@@ -%s +%s @@%s", range1, range2, diff.Eol); err != nil {
-			return err
-		}
-		for _, c := range g {
-			i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
-			if c.Tag == 'e' {
-				for _, line := range diff.A[i1:i2] {
-					if err := ws(" " + line); err != nil {
-						return err
-					}
-				}
-				continue
-			}
-			if c.Tag == 'r' || c.Tag == 'd' {
-				for _, line := range diff.A[i1:i2] {
-					if err := ws("-" + line); err != nil {
-						return err
-					}
-				}
-			}
-			if c.Tag == 'r' || c.Tag == 'i' {
-				for _, line := range diff.B[j1:j2] {
-					if err := ws("+" + line); err != nil {
-						return err
-					}
-				}
-			}
-		}
-	}
-	return nil
-}
-
-// Like WriteUnifiedDiff but returns the diff a string.
-func GetUnifiedDiffString(diff UnifiedDiff) (string, error) {
-	w := &bytes.Buffer{}
-	err := WriteUnifiedDiff(w, diff)
-	return string(w.Bytes()), err
-}
-
-// Convert range to the "ed" format.
-func formatRangeContext(start, stop int) string {
-	// Per the diff spec at http://www.unix.org/single_unix_specification/
-	beginning := start + 1 // lines start numbering with one
-	length := stop - start
-	if length == 0 {
-		beginning -= 1 // empty ranges begin at line just before the range
-	}
-	if length <= 1 {
-		return fmt.Sprintf("%d", beginning)
-	}
-	return fmt.Sprintf("%d,%d", beginning, beginning+length-1)
-}
-
-type ContextDiff UnifiedDiff
-
-// Compare two sequences of lines; generate the delta as a context diff.
-//
-// Context diffs are a compact way of showing line changes and a few
-// lines of context. The number of context lines is set by diff.Context
-// which defaults to three.
-//
-// By default, the diff control lines (those with *** or ---) are
-// created with a trailing newline.
-//
-// For inputs that do not have trailing newlines, set the diff.Eol
-// argument to "" so that the output will be uniformly newline free.
-//
-// The context diff format normally has a header for filenames and
-// modification times.  Any or all of these may be specified using
-// strings for diff.FromFile, diff.ToFile, diff.FromDate, diff.ToDate.
-// The modification times are normally expressed in the ISO 8601 format.
-// If not specified, the strings default to blanks.
-func WriteContextDiff(writer io.Writer, diff ContextDiff) error {
-	buf := bufio.NewWriter(writer)
-	defer buf.Flush()
-	var diffErr error
-	wf := func(format string, args ...interface{}) {
-		_, err := buf.WriteString(fmt.Sprintf(format, args...))
-		if diffErr == nil && err != nil {
-			diffErr = err
-		}
-	}
-	ws := func(s string) {
-		_, err := buf.WriteString(s)
-		if diffErr == nil && err != nil {
-			diffErr = err
-		}
-	}
-
-	if len(diff.Eol) == 0 {
-		diff.Eol = "\n"
-	}
-
-	prefix := map[byte]string{
-		'i': "+ ",
-		'd': "- ",
-		'r': "! ",
-		'e': "  ",
-	}
-
-	started := false
-	m := NewMatcher(diff.A, diff.B)
-	for _, g := range m.GetGroupedOpCodes(diff.Context) {
-		if !started {
-			started = true
-			fromDate := ""
-			if len(diff.FromDate) > 0 {
-				fromDate = "\t" + diff.FromDate
-			}
-			toDate := ""
-			if len(diff.ToDate) > 0 {
-				toDate = "\t" + diff.ToDate
-			}
-			if diff.FromFile != "" || diff.ToFile != "" {
-				wf("*** %s%s%s", diff.FromFile, fromDate, diff.Eol)
-				wf("--- %s%s%s", diff.ToFile, toDate, diff.Eol)
-			}
-		}
-
-		first, last := g[0], g[len(g)-1]
-		ws("***************" + diff.Eol)
-
-		range1 := formatRangeContext(first.I1, last.I2)
-		wf("*** %s ****%s", range1, diff.Eol)
-		for _, c := range g {
-			if c.Tag == 'r' || c.Tag == 'd' {
-				for _, cc := range g {
-					if cc.Tag == 'i' {
-						continue
-					}
-					for _, line := range diff.A[cc.I1:cc.I2] {
-						ws(prefix[cc.Tag] + line)
-					}
-				}
-				break
-			}
-		}
-
-		range2 := formatRangeContext(first.J1, last.J2)
-		wf("--- %s ----%s", range2, diff.Eol)
-		for _, c := range g {
-			if c.Tag == 'r' || c.Tag == 'i' {
-				for _, cc := range g {
-					if cc.Tag == 'd' {
-						continue
-					}
-					for _, line := range diff.B[cc.J1:cc.J2] {
-						ws(prefix[cc.Tag] + line)
-					}
-				}
-				break
-			}
-		}
-	}
-	return diffErr
-}
-
-// Like WriteContextDiff but returns the diff a string.
-func GetContextDiffString(diff ContextDiff) (string, error) {
-	w := &bytes.Buffer{}
-	err := WriteContextDiff(w, diff)
-	return string(w.Bytes()), err
-}
-
-// Split a string on "\n" while preserving them. The output can be used
-// as input for UnifiedDiff and ContextDiff structures.
-func SplitLines(s string) []string {
-	lines := strings.SplitAfter(s, "\n")
-	lines[len(lines)-1] += "\n"
-	return lines
-}