diff options
Diffstat (limited to 'vendor/github.com/google/go-cmp/cmp/report_text.go')
-rw-r--r-- | vendor/github.com/google/go-cmp/cmp/report_text.go | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/vendor/github.com/google/go-cmp/cmp/report_text.go b/vendor/github.com/google/go-cmp/cmp/report_text.go new file mode 100644 index 000000000..0fd46d7ff --- /dev/null +++ b/vendor/github.com/google/go-cmp/cmp/report_text.go @@ -0,0 +1,431 @@ +// Copyright 2019, 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. + +package cmp + +import ( + "bytes" + "fmt" + "math/rand" + "strings" + "time" + "unicode/utf8" + + "github.com/google/go-cmp/cmp/internal/flags" +) + +var randBool = rand.New(rand.NewSource(time.Now().Unix())).Intn(2) == 0 + +const maxColumnLength = 80 + +type indentMode int + +func (n indentMode) appendIndent(b []byte, d diffMode) []byte { + // The output of Diff is documented as being unstable to provide future + // flexibility in changing the output for more humanly readable reports. + // This logic intentionally introduces instability to the exact output + // so that users can detect accidental reliance on stability early on, + // rather than much later when an actual change to the format occurs. + if flags.Deterministic || randBool { + // Use regular spaces (U+0020). + switch d { + case diffUnknown, diffIdentical: + b = append(b, " "...) + case diffRemoved: + b = append(b, "- "...) + case diffInserted: + b = append(b, "+ "...) + } + } else { + // Use non-breaking spaces (U+00a0). + switch d { + case diffUnknown, diffIdentical: + b = append(b, " "...) + case diffRemoved: + b = append(b, "- "...) + case diffInserted: + b = append(b, "+ "...) + } + } + return repeatCount(n).appendChar(b, '\t') +} + +type repeatCount int + +func (n repeatCount) appendChar(b []byte, c byte) []byte { + for ; n > 0; n-- { + b = append(b, c) + } + return b +} + +// textNode is a simplified tree-based representation of structured text. +// Possible node types are textWrap, textList, or textLine. +type textNode interface { + // Len reports the length in bytes of a single-line version of the tree. + // Nested textRecord.Diff and textRecord.Comment fields are ignored. + Len() int + // Equal reports whether the two trees are structurally identical. + // Nested textRecord.Diff and textRecord.Comment fields are compared. + Equal(textNode) bool + // String returns the string representation of the text tree. + // It is not guaranteed that len(x.String()) == x.Len(), + // nor that x.String() == y.String() implies that x.Equal(y). + String() string + + // formatCompactTo formats the contents of the tree as a single-line string + // to the provided buffer. Any nested textRecord.Diff and textRecord.Comment + // fields are ignored. + // + // However, not all nodes in the tree should be collapsed as a single-line. + // If a node can be collapsed as a single-line, it is replaced by a textLine + // node. Since the top-level node cannot replace itself, this also returns + // the current node itself. + // + // This does not mutate the receiver. + formatCompactTo([]byte, diffMode) ([]byte, textNode) + // formatExpandedTo formats the contents of the tree as a multi-line string + // to the provided buffer. In order for column alignment to operate well, + // formatCompactTo must be called before calling formatExpandedTo. + formatExpandedTo([]byte, diffMode, indentMode) []byte +} + +// textWrap is a wrapper that concatenates a prefix and/or a suffix +// to the underlying node. +type textWrap struct { + Prefix string // e.g., "bytes.Buffer{" + Value textNode // textWrap | textList | textLine + Suffix string // e.g., "}" + Metadata interface{} // arbitrary metadata; has no effect on formatting +} + +func (s *textWrap) Len() int { + return len(s.Prefix) + s.Value.Len() + len(s.Suffix) +} +func (s1 *textWrap) Equal(s2 textNode) bool { + if s2, ok := s2.(*textWrap); ok { + return s1.Prefix == s2.Prefix && s1.Value.Equal(s2.Value) && s1.Suffix == s2.Suffix + } + return false +} +func (s *textWrap) String() string { + var d diffMode + var n indentMode + _, s2 := s.formatCompactTo(nil, d) + b := n.appendIndent(nil, d) // Leading indent + b = s2.formatExpandedTo(b, d, n) // Main body + b = append(b, '\n') // Trailing newline + return string(b) +} +func (s *textWrap) formatCompactTo(b []byte, d diffMode) ([]byte, textNode) { + n0 := len(b) // Original buffer length + b = append(b, s.Prefix...) + b, s.Value = s.Value.formatCompactTo(b, d) + b = append(b, s.Suffix...) + if _, ok := s.Value.(textLine); ok { + return b, textLine(b[n0:]) + } + return b, s +} +func (s *textWrap) formatExpandedTo(b []byte, d diffMode, n indentMode) []byte { + b = append(b, s.Prefix...) + b = s.Value.formatExpandedTo(b, d, n) + b = append(b, s.Suffix...) + return b +} + +// textList is a comma-separated list of textWrap or textLine nodes. +// The list may be formatted as multi-lines or single-line at the discretion +// of the textList.formatCompactTo method. +type textList []textRecord +type textRecord struct { + Diff diffMode // e.g., 0 or '-' or '+' + Key string // e.g., "MyField" + Value textNode // textWrap | textLine + ElideComma bool // avoid trailing comma + Comment fmt.Stringer // e.g., "6 identical fields" +} + +// AppendEllipsis appends a new ellipsis node to the list if none already +// exists at the end. If cs is non-zero it coalesces the statistics with the +// previous diffStats. +func (s *textList) AppendEllipsis(ds diffStats) { + hasStats := !ds.IsZero() + if len(*s) == 0 || !(*s)[len(*s)-1].Value.Equal(textEllipsis) { + if hasStats { + *s = append(*s, textRecord{Value: textEllipsis, ElideComma: true, Comment: ds}) + } else { + *s = append(*s, textRecord{Value: textEllipsis, ElideComma: true}) + } + return + } + if hasStats { + (*s)[len(*s)-1].Comment = (*s)[len(*s)-1].Comment.(diffStats).Append(ds) + } +} + +func (s textList) Len() (n int) { + for i, r := range s { + n += len(r.Key) + if r.Key != "" { + n += len(": ") + } + n += r.Value.Len() + if i < len(s)-1 { + n += len(", ") + } + } + return n +} + +func (s1 textList) Equal(s2 textNode) bool { + if s2, ok := s2.(textList); ok { + if len(s1) != len(s2) { + return false + } + for i := range s1 { + r1, r2 := s1[i], s2[i] + if !(r1.Diff == r2.Diff && r1.Key == r2.Key && r1.Value.Equal(r2.Value) && r1.Comment == r2.Comment) { + return false + } + } + return true + } + return false +} + +func (s textList) String() string { + return (&textWrap{Prefix: "{", Value: s, Suffix: "}"}).String() +} + +func (s textList) formatCompactTo(b []byte, d diffMode) ([]byte, textNode) { + s = append(textList(nil), s...) // Avoid mutating original + + // Determine whether we can collapse this list as a single line. + n0 := len(b) // Original buffer length + var multiLine bool + for i, r := range s { + if r.Diff == diffInserted || r.Diff == diffRemoved { + multiLine = true + } + b = append(b, r.Key...) + if r.Key != "" { + b = append(b, ": "...) + } + b, s[i].Value = r.Value.formatCompactTo(b, d|r.Diff) + if _, ok := s[i].Value.(textLine); !ok { + multiLine = true + } + if r.Comment != nil { + multiLine = true + } + if i < len(s)-1 { + b = append(b, ", "...) + } + } + // Force multi-lined output when printing a removed/inserted node that + // is sufficiently long. + if (d == diffInserted || d == diffRemoved) && len(b[n0:]) > maxColumnLength { + multiLine = true + } + if !multiLine { + return b, textLine(b[n0:]) + } + return b, s +} + +func (s textList) formatExpandedTo(b []byte, d diffMode, n indentMode) []byte { + alignKeyLens := s.alignLens( + func(r textRecord) bool { + _, isLine := r.Value.(textLine) + return r.Key == "" || !isLine + }, + func(r textRecord) int { return utf8.RuneCountInString(r.Key) }, + ) + alignValueLens := s.alignLens( + func(r textRecord) bool { + _, isLine := r.Value.(textLine) + return !isLine || r.Value.Equal(textEllipsis) || r.Comment == nil + }, + func(r textRecord) int { return utf8.RuneCount(r.Value.(textLine)) }, + ) + + // Format lists of simple lists in a batched form. + // If the list is sequence of only textLine values, + // then batch multiple values on a single line. + var isSimple bool + for _, r := range s { + _, isLine := r.Value.(textLine) + isSimple = r.Diff == 0 && r.Key == "" && isLine && r.Comment == nil + if !isSimple { + break + } + } + if isSimple { + n++ + var batch []byte + emitBatch := func() { + if len(batch) > 0 { + b = n.appendIndent(append(b, '\n'), d) + b = append(b, bytes.TrimRight(batch, " ")...) + batch = batch[:0] + } + } + for _, r := range s { + line := r.Value.(textLine) + if len(batch)+len(line)+len(", ") > maxColumnLength { + emitBatch() + } + batch = append(batch, line...) + batch = append(batch, ", "...) + } + emitBatch() + n-- + return n.appendIndent(append(b, '\n'), d) + } + + // Format the list as a multi-lined output. + n++ + for i, r := range s { + b = n.appendIndent(append(b, '\n'), d|r.Diff) + if r.Key != "" { + b = append(b, r.Key+": "...) + } + b = alignKeyLens[i].appendChar(b, ' ') + + b = r.Value.formatExpandedTo(b, d|r.Diff, n) + if !r.ElideComma { + b = append(b, ',') + } + b = alignValueLens[i].appendChar(b, ' ') + + if r.Comment != nil { + b = append(b, " // "+r.Comment.String()...) + } + } + n-- + + return n.appendIndent(append(b, '\n'), d) +} + +func (s textList) alignLens( + skipFunc func(textRecord) bool, + lenFunc func(textRecord) int, +) []repeatCount { + var startIdx, endIdx, maxLen int + lens := make([]repeatCount, len(s)) + for i, r := range s { + if skipFunc(r) { + for j := startIdx; j < endIdx && j < len(s); j++ { + lens[j] = repeatCount(maxLen - lenFunc(s[j])) + } + startIdx, endIdx, maxLen = i+1, i+1, 0 + } else { + if maxLen < lenFunc(r) { + maxLen = lenFunc(r) + } + endIdx = i + 1 + } + } + for j := startIdx; j < endIdx && j < len(s); j++ { + lens[j] = repeatCount(maxLen - lenFunc(s[j])) + } + return lens +} + +// textLine is a single-line segment of text and is always a leaf node +// in the textNode tree. +type textLine []byte + +var ( + textNil = textLine("nil") + textEllipsis = textLine("...") +) + +func (s textLine) Len() int { + return len(s) +} +func (s1 textLine) Equal(s2 textNode) bool { + if s2, ok := s2.(textLine); ok { + return bytes.Equal([]byte(s1), []byte(s2)) + } + return false +} +func (s textLine) String() string { + return string(s) +} +func (s textLine) formatCompactTo(b []byte, d diffMode) ([]byte, textNode) { + return append(b, s...), s +} +func (s textLine) formatExpandedTo(b []byte, _ diffMode, _ indentMode) []byte { + return append(b, s...) +} + +type diffStats struct { + Name string + NumIgnored int + NumIdentical int + NumRemoved int + NumInserted int + NumModified int +} + +func (s diffStats) IsZero() bool { + s.Name = "" + return s == diffStats{} +} + +func (s diffStats) NumDiff() int { + return s.NumRemoved + s.NumInserted + s.NumModified +} + +func (s diffStats) Append(ds diffStats) diffStats { + assert(s.Name == ds.Name) + s.NumIgnored += ds.NumIgnored + s.NumIdentical += ds.NumIdentical + s.NumRemoved += ds.NumRemoved + s.NumInserted += ds.NumInserted + s.NumModified += ds.NumModified + return s +} + +// String prints a humanly-readable summary of coalesced records. +// +// Example: +// diffStats{Name: "Field", NumIgnored: 5}.String() => "5 ignored fields" +func (s diffStats) String() string { + var ss []string + var sum int + labels := [...]string{"ignored", "identical", "removed", "inserted", "modified"} + counts := [...]int{s.NumIgnored, s.NumIdentical, s.NumRemoved, s.NumInserted, s.NumModified} + for i, n := range counts { + if n > 0 { + ss = append(ss, fmt.Sprintf("%d %v", n, labels[i])) + } + sum += n + } + + // Pluralize the name (adjusting for some obscure English grammar rules). + name := s.Name + if sum > 1 { + name += "s" + if strings.HasSuffix(name, "ys") { + name = name[:len(name)-2] + "ies" // e.g., "entrys" => "entries" + } + } + + // Format the list according to English grammar (with Oxford comma). + switch n := len(ss); n { + case 0: + return "" + case 1, 2: + return strings.Join(ss, " and ") + " " + name + default: + return strings.Join(ss[:n-1], ", ") + ", and " + ss[n-1] + " " + name + } +} + +type commentString string + +func (s commentString) String() string { return string(s) } |