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-rw-r--r--vendor/github.com/google/go-cmp/cmp/internal/value/format.go277
1 files changed, 277 insertions, 0 deletions
diff --git a/vendor/github.com/google/go-cmp/cmp/internal/value/format.go b/vendor/github.com/google/go-cmp/cmp/internal/value/format.go
new file mode 100644
index 00000000..657e5087
--- /dev/null
+++ b/vendor/github.com/google/go-cmp/cmp/internal/value/format.go
@@ -0,0 +1,277 @@
+// Copyright 2017, 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 value provides functionality for reflect.Value types.
+package value
+
+import (
+ "fmt"
+ "reflect"
+ "strconv"
+ "strings"
+ "unicode"
+)
+
+var stringerIface = reflect.TypeOf((*fmt.Stringer)(nil)).Elem()
+
+// Format formats the value v as a string.
+//
+// This is similar to fmt.Sprintf("%+v", v) except this:
+// * Prints the type unless it can be elided
+// * Avoids printing struct fields that are zero
+// * Prints a nil-slice as being nil, not empty
+// * Prints map entries in deterministic order
+func Format(v reflect.Value, conf FormatConfig) string {
+ conf.printType = true
+ conf.followPointers = true
+ conf.realPointers = true
+ return formatAny(v, conf, nil)
+}
+
+type FormatConfig struct {
+ UseStringer bool // Should the String method be used if available?
+ printType bool // Should we print the type before the value?
+ PrintPrimitiveType bool // Should we print the type of primitives?
+ followPointers bool // Should we recursively follow pointers?
+ realPointers bool // Should we print the real address of pointers?
+}
+
+func formatAny(v reflect.Value, conf FormatConfig, visited map[uintptr]bool) string {
+ // TODO: Should this be a multi-line printout in certain situations?
+
+ if !v.IsValid() {
+ return "<non-existent>"
+ }
+ if conf.UseStringer && v.Type().Implements(stringerIface) && v.CanInterface() {
+ if (v.Kind() == reflect.Ptr || v.Kind() == reflect.Interface) && v.IsNil() {
+ return "<nil>"
+ }
+
+ const stringerPrefix = "s" // Indicates that the String method was used
+ s := v.Interface().(fmt.Stringer).String()
+ return stringerPrefix + formatString(s)
+ }
+
+ switch v.Kind() {
+ case reflect.Bool:
+ return formatPrimitive(v.Type(), v.Bool(), conf)
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return formatPrimitive(v.Type(), v.Int(), conf)
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ if v.Type().PkgPath() == "" || v.Kind() == reflect.Uintptr {
+ // Unnamed uints are usually bytes or words, so use hexadecimal.
+ return formatPrimitive(v.Type(), formatHex(v.Uint()), conf)
+ }
+ return formatPrimitive(v.Type(), v.Uint(), conf)
+ case reflect.Float32, reflect.Float64:
+ return formatPrimitive(v.Type(), v.Float(), conf)
+ case reflect.Complex64, reflect.Complex128:
+ return formatPrimitive(v.Type(), v.Complex(), conf)
+ case reflect.String:
+ return formatPrimitive(v.Type(), formatString(v.String()), conf)
+ case reflect.UnsafePointer, reflect.Chan, reflect.Func:
+ return formatPointer(v, conf)
+ case reflect.Ptr:
+ if v.IsNil() {
+ if conf.printType {
+ return fmt.Sprintf("(%v)(nil)", v.Type())
+ }
+ return "<nil>"
+ }
+ if visited[v.Pointer()] || !conf.followPointers {
+ return formatPointer(v, conf)
+ }
+ visited = insertPointer(visited, v.Pointer())
+ return "&" + formatAny(v.Elem(), conf, visited)
+ case reflect.Interface:
+ if v.IsNil() {
+ if conf.printType {
+ return fmt.Sprintf("%v(nil)", v.Type())
+ }
+ return "<nil>"
+ }
+ return formatAny(v.Elem(), conf, visited)
+ case reflect.Slice:
+ if v.IsNil() {
+ if conf.printType {
+ return fmt.Sprintf("%v(nil)", v.Type())
+ }
+ return "<nil>"
+ }
+ if visited[v.Pointer()] {
+ return formatPointer(v, conf)
+ }
+ visited = insertPointer(visited, v.Pointer())
+ fallthrough
+ case reflect.Array:
+ var ss []string
+ subConf := conf
+ subConf.printType = v.Type().Elem().Kind() == reflect.Interface
+ for i := 0; i < v.Len(); i++ {
+ s := formatAny(v.Index(i), subConf, visited)
+ ss = append(ss, s)
+ }
+ s := fmt.Sprintf("{%s}", strings.Join(ss, ", "))
+ if conf.printType {
+ return v.Type().String() + s
+ }
+ return s
+ case reflect.Map:
+ if v.IsNil() {
+ if conf.printType {
+ return fmt.Sprintf("%v(nil)", v.Type())
+ }
+ return "<nil>"
+ }
+ if visited[v.Pointer()] {
+ return formatPointer(v, conf)
+ }
+ visited = insertPointer(visited, v.Pointer())
+
+ var ss []string
+ keyConf, valConf := conf, conf
+ keyConf.printType = v.Type().Key().Kind() == reflect.Interface
+ keyConf.followPointers = false
+ valConf.printType = v.Type().Elem().Kind() == reflect.Interface
+ for _, k := range SortKeys(v.MapKeys()) {
+ sk := formatAny(k, keyConf, visited)
+ sv := formatAny(v.MapIndex(k), valConf, visited)
+ ss = append(ss, fmt.Sprintf("%s: %s", sk, sv))
+ }
+ s := fmt.Sprintf("{%s}", strings.Join(ss, ", "))
+ if conf.printType {
+ return v.Type().String() + s
+ }
+ return s
+ case reflect.Struct:
+ var ss []string
+ subConf := conf
+ subConf.printType = true
+ for i := 0; i < v.NumField(); i++ {
+ vv := v.Field(i)
+ if isZero(vv) {
+ continue // Elide zero value fields
+ }
+ name := v.Type().Field(i).Name
+ subConf.UseStringer = conf.UseStringer
+ s := formatAny(vv, subConf, visited)
+ ss = append(ss, fmt.Sprintf("%s: %s", name, s))
+ }
+ s := fmt.Sprintf("{%s}", strings.Join(ss, ", "))
+ if conf.printType {
+ return v.Type().String() + s
+ }
+ return s
+ default:
+ panic(fmt.Sprintf("%v kind not handled", v.Kind()))
+ }
+}
+
+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)
+ }
+ if strings.IndexFunc(s, rawInvalid) < 0 {
+ return "`" + s + "`"
+ }
+ return qs
+}
+
+func formatPrimitive(t reflect.Type, v interface{}, conf FormatConfig) string {
+ if conf.printType && (conf.PrintPrimitiveType || t.PkgPath() != "") {
+ return fmt.Sprintf("%v(%v)", t, v)
+ }
+ return fmt.Sprintf("%v", v)
+}
+
+func formatPointer(v reflect.Value, conf FormatConfig) string {
+ p := v.Pointer()
+ if !conf.realPointers {
+ p = 0 // For deterministic printing purposes
+ }
+ s := formatHex(uint64(p))
+ if conf.printType {
+ return fmt.Sprintf("(%v)(%s)", v.Type(), s)
+ }
+ return s
+}
+
+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)
+}
+
+// insertPointer insert p into m, allocating m if necessary.
+func insertPointer(m map[uintptr]bool, p uintptr) map[uintptr]bool {
+ if m == nil {
+ m = make(map[uintptr]bool)
+ }
+ m[p] = true
+ return m
+}
+
+// isZero reports whether v is the zero value.
+// This does not rely on Interface and so can be used on unexported fields.
+func isZero(v reflect.Value) bool {
+ switch v.Kind() {
+ case reflect.Bool:
+ return v.Bool() == false
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return v.Int() == 0
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ return v.Uint() == 0
+ case reflect.Float32, reflect.Float64:
+ return v.Float() == 0
+ case reflect.Complex64, reflect.Complex128:
+ return v.Complex() == 0
+ case reflect.String:
+ return v.String() == ""
+ case reflect.UnsafePointer:
+ return v.Pointer() == 0
+ case reflect.Chan, reflect.Func, reflect.Interface, reflect.Ptr, reflect.Map, reflect.Slice:
+ return v.IsNil()
+ case reflect.Array:
+ for i := 0; i < v.Len(); i++ {
+ if !isZero(v.Index(i)) {
+ return false
+ }
+ }
+ return true
+ case reflect.Struct:
+ for i := 0; i < v.NumField(); i++ {
+ if !isZero(v.Field(i)) {
+ return false
+ }
+ }
+ return true
+ }
+ return false
+}