diff options
Diffstat (limited to 'vendor/github.com/google/go-cmp/cmp/report_reflect.go')
-rw-r--r-- | vendor/github.com/google/go-cmp/cmp/report_reflect.go | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/vendor/github.com/google/go-cmp/cmp/report_reflect.go b/vendor/github.com/google/go-cmp/cmp/report_reflect.go new file mode 100644 index 0000000..2761b62 --- /dev/null +++ b/vendor/github.com/google/go-cmp/cmp/report_reflect.go @@ -0,0 +1,278 @@ +// 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.md file. + +package cmp + +import ( + "fmt" + "reflect" + "strconv" + "strings" + "unicode" + + "github.com/google/go-cmp/cmp/internal/flags" + "github.com/google/go-cmp/cmp/internal/value" +) + +type formatValueOptions struct { + // AvoidStringer controls whether to avoid calling custom stringer + // methods like error.Error or fmt.Stringer.String. + AvoidStringer bool + + // ShallowPointers controls whether to avoid descending into pointers. + // Useful when printing map keys, where pointer comparison is performed + // on the pointer address rather than the pointed-at value. + ShallowPointers bool + + // PrintAddresses controls whether to print the address of all pointers, + // slice elements, and maps. + PrintAddresses bool +} + +// FormatType prints the type as if it were wrapping s. +// This may return s as-is depending on the current type and TypeMode mode. +func (opts formatOptions) FormatType(t reflect.Type, s textNode) textNode { + // Check whether to emit the type or not. + switch opts.TypeMode { + case autoType: + switch t.Kind() { + case reflect.Struct, reflect.Slice, reflect.Array, reflect.Map: + if s.Equal(textNil) { + return s + } + default: + return s + } + case elideType: + return s + } + + // Determine the type label, applying special handling for unnamed types. + typeName := t.String() + if t.Name() == "" { + // According to Go grammar, certain type literals contain symbols that + // do not strongly bind to the next lexicographical token (e.g., *T). + switch t.Kind() { + case reflect.Chan, reflect.Func, reflect.Ptr: + typeName = "(" + typeName + ")" + } + typeName = strings.Replace(typeName, "struct {", "struct{", -1) + typeName = strings.Replace(typeName, "interface {", "interface{", -1) + } + + // Avoid wrap the value in parenthesis if unnecessary. + if s, ok := s.(textWrap); ok { + hasParens := strings.HasPrefix(s.Prefix, "(") && strings.HasSuffix(s.Suffix, ")") + hasBraces := strings.HasPrefix(s.Prefix, "{") && strings.HasSuffix(s.Suffix, "}") + if hasParens || hasBraces { + return textWrap{typeName, s, ""} + } + } + return textWrap{typeName + "(", s, ")"} +} + +// FormatValue prints the reflect.Value, taking extra care to avoid descending +// into pointers already in m. As pointers are visited, m is also updated. +func (opts formatOptions) FormatValue(v reflect.Value, m visitedPointers) (out textNode) { + if !v.IsValid() { + return nil + } + t := v.Type() + + // Check whether there is an Error or String method to call. + if !opts.AvoidStringer && v.CanInterface() { + // Avoid calling Error or String methods on nil receivers since many + // implementations crash when doing so. + if (t.Kind() != reflect.Ptr && t.Kind() != reflect.Interface) || !v.IsNil() { + switch v := v.Interface().(type) { + case error: + return textLine("e" + formatString(v.Error())) + case fmt.Stringer: + return textLine("s" + formatString(v.String())) + } + } + } + + // Check whether to explicitly wrap the result with the type. + var skipType bool + defer func() { + if !skipType { + out = opts.FormatType(t, out) + } + }() + + var ptr string + switch t.Kind() { + case reflect.Bool: + return textLine(fmt.Sprint(v.Bool())) + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + return textLine(fmt.Sprint(v.Int())) + case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: + // Unnamed uints are usually bytes or words, so use hexadecimal. + if t.PkgPath() == "" || t.Kind() == reflect.Uintptr { + return textLine(formatHex(v.Uint())) + } + return textLine(fmt.Sprint(v.Uint())) + case reflect.Float32, reflect.Float64: + return textLine(fmt.Sprint(v.Float())) + case reflect.Complex64, reflect.Complex128: + return textLine(fmt.Sprint(v.Complex())) + case reflect.String: + return textLine(formatString(v.String())) + case reflect.UnsafePointer, reflect.Chan, reflect.Func: + return textLine(formatPointer(v)) + case reflect.Struct: + var list textList + for i := 0; i < v.NumField(); i++ { + vv := v.Field(i) + if value.IsZero(vv) { + continue // Elide fields with zero values + } + s := opts.WithTypeMode(autoType).FormatValue(vv, m) + list = append(list, textRecord{Key: t.Field(i).Name, Value: s}) + } + return textWrap{"{", list, "}"} + case reflect.Slice: + if v.IsNil() { + return textNil + } + if opts.PrintAddresses { + ptr = formatPointer(v) + } + fallthrough + case reflect.Array: + var list textList + for i := 0; i < v.Len(); i++ { + vi := v.Index(i) + if vi.CanAddr() { // Check for cyclic elements + p := vi.Addr() + if m.Visit(p) { + var out textNode + out = textLine(formatPointer(p)) + out = opts.WithTypeMode(emitType).FormatType(p.Type(), out) + out = textWrap{"*", out, ""} + list = append(list, textRecord{Value: out}) + continue + } + } + s := opts.WithTypeMode(elideType).FormatValue(vi, m) + list = append(list, textRecord{Value: s}) + } + return textWrap{ptr + "{", list, "}"} + case reflect.Map: + if v.IsNil() { + return textNil + } + if m.Visit(v) { + return textLine(formatPointer(v)) + } + + var list textList + for _, k := range value.SortKeys(v.MapKeys()) { + sk := formatMapKey(k) + sv := opts.WithTypeMode(elideType).FormatValue(v.MapIndex(k), m) + list = append(list, textRecord{Key: sk, Value: sv}) + } + if opts.PrintAddresses { + ptr = formatPointer(v) + } + return textWrap{ptr + "{", list, "}"} + case reflect.Ptr: + if v.IsNil() { + return textNil + } + if m.Visit(v) || opts.ShallowPointers { + return textLine(formatPointer(v)) + } + if opts.PrintAddresses { + ptr = formatPointer(v) + } + skipType = true // Let the underlying value print the type instead + return textWrap{"&" + ptr, opts.FormatValue(v.Elem(), m), ""} + case reflect.Interface: + if v.IsNil() { + return textNil + } + // Interfaces accept different concrete types, + // so configure the underlying value to explicitly print the type. + skipType = true // Print the concrete type instead + return opts.WithTypeMode(emitType).FormatValue(v.Elem(), m) + default: + panic(fmt.Sprintf("%v kind not handled", v.Kind())) + } +} + +// formatMapKey formats v as if it were a map key. +// The result is guaranteed to be a single line. +func formatMapKey(v reflect.Value) string { + var opts formatOptions + opts.TypeMode = elideType + opts.ShallowPointers = true + s := opts.FormatValue(v, visitedPointers{}).String() + return strings.TrimSpace(s) +} + +// formatString prints s as a double-quoted or backtick-quoted string. +func formatString(s string) string { + // Use quoted string if it the same length as a raw string literal. + // Otherwise, attempt to use the raw string form. + qs := strconv.Quote(s) + if len(qs) == 1+len(s)+1 { + return qs + } + + // Disallow newlines to ensure output is a single line. + // Only allow printable runes for readability purposes. + rawInvalid := func(r rune) bool { + return r == '`' || r == '\n' || !(unicode.IsPrint(r) || r == '\t') + } + if strings.IndexFunc(s, rawInvalid) < 0 { + return "`" + s + "`" + } + return qs +} + +// formatHex prints u as a hexadecimal integer in Go notation. +func formatHex(u uint64) string { + var f string + switch { + case u <= 0xff: + f = "0x%02x" + case u <= 0xffff: + f = "0x%04x" + case u <= 0xffffff: + f = "0x%06x" + case u <= 0xffffffff: + f = "0x%08x" + case u <= 0xffffffffff: + f = "0x%010x" + case u <= 0xffffffffffff: + f = "0x%012x" + case u <= 0xffffffffffffff: + f = "0x%014x" + case u <= 0xffffffffffffffff: + f = "0x%016x" + } + return fmt.Sprintf(f, u) +} + +// formatPointer prints the address of the pointer. +func formatPointer(v reflect.Value) string { + p := v.Pointer() + if flags.Deterministic { + p = 0xdeadf00f // Only used for stable testing purposes + } + return fmt.Sprintf("⟪0x%x⟫", p) +} + +type visitedPointers map[value.Pointer]struct{} + +// Visit inserts pointer v into the visited map and reports whether it had +// already been visited before. +func (m visitedPointers) Visit(v reflect.Value) bool { + p := value.PointerOf(v) + _, visited := m[p] + m[p] = struct{}{} + return visited +} |