aboutsummaryrefslogtreecommitdiff
path: root/vendor/github.com/davecgh/go-spew/spew/bypass.go
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/github.com/davecgh/go-spew/spew/bypass.go')
-rw-r--r--vendor/github.com/davecgh/go-spew/spew/bypass.go145
1 files changed, 0 insertions, 145 deletions
diff --git a/vendor/github.com/davecgh/go-spew/spew/bypass.go b/vendor/github.com/davecgh/go-spew/spew/bypass.go
deleted file mode 100644
index 7929947..0000000
--- a/vendor/github.com/davecgh/go-spew/spew/bypass.go
+++ /dev/null
@@ -1,145 +0,0 @@
-// Copyright (c) 2015-2016 Dave Collins <dave@davec.name>
-//
-// Permission to use, copy, modify, and distribute this software for any
-// purpose with or without fee is hereby granted, provided that the above
-// copyright notice and this permission notice appear in all copies.
-//
-// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
-// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
-// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
-// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
-// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
-// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-
-// NOTE: Due to the following build constraints, this file will only be compiled
-// when the code is not running on Google App Engine, compiled by GopherJS, and
-// "-tags safe" is not added to the go build command line. The "disableunsafe"
-// tag is deprecated and thus should not be used.
-// Go versions prior to 1.4 are disabled because they use a different layout
-// for interfaces which make the implementation of unsafeReflectValue more complex.
-// +build !js,!appengine,!safe,!disableunsafe,go1.4
-
-package spew
-
-import (
- "reflect"
- "unsafe"
-)
-
-const (
- // UnsafeDisabled is a build-time constant which specifies whether or
- // not access to the unsafe package is available.
- UnsafeDisabled = false
-
- // ptrSize is the size of a pointer on the current arch.
- ptrSize = unsafe.Sizeof((*byte)(nil))
-)
-
-type flag uintptr
-
-var (
- // flagRO indicates whether the value field of a reflect.Value
- // is read-only.
- flagRO flag
-
- // flagAddr indicates whether the address of the reflect.Value's
- // value may be taken.
- flagAddr flag
-)
-
-// flagKindMask holds the bits that make up the kind
-// part of the flags field. In all the supported versions,
-// it is in the lower 5 bits.
-const flagKindMask = flag(0x1f)
-
-// Different versions of Go have used different
-// bit layouts for the flags type. This table
-// records the known combinations.
-var okFlags = []struct {
- ro, addr flag
-}{{
- // From Go 1.4 to 1.5
- ro: 1 << 5,
- addr: 1 << 7,
-}, {
- // Up to Go tip.
- ro: 1<<5 | 1<<6,
- addr: 1 << 8,
-}}
-
-var flagValOffset = func() uintptr {
- field, ok := reflect.TypeOf(reflect.Value{}).FieldByName("flag")
- if !ok {
- panic("reflect.Value has no flag field")
- }
- return field.Offset
-}()
-
-// flagField returns a pointer to the flag field of a reflect.Value.
-func flagField(v *reflect.Value) *flag {
- return (*flag)(unsafe.Pointer(uintptr(unsafe.Pointer(v)) + flagValOffset))
-}
-
-// unsafeReflectValue converts the passed reflect.Value into a one that bypasses
-// the typical safety restrictions preventing access to unaddressable and
-// unexported data. It works by digging the raw pointer to the underlying
-// value out of the protected value and generating a new unprotected (unsafe)
-// reflect.Value to it.
-//
-// This allows us to check for implementations of the Stringer and error
-// interfaces to be used for pretty printing ordinarily unaddressable and
-// inaccessible values such as unexported struct fields.
-func unsafeReflectValue(v reflect.Value) reflect.Value {
- if !v.IsValid() || (v.CanInterface() && v.CanAddr()) {
- return v
- }
- flagFieldPtr := flagField(&v)
- *flagFieldPtr &^= flagRO
- *flagFieldPtr |= flagAddr
- return v
-}
-
-// Sanity checks against future reflect package changes
-// to the type or semantics of the Value.flag field.
-func init() {
- field, ok := reflect.TypeOf(reflect.Value{}).FieldByName("flag")
- if !ok {
- panic("reflect.Value has no flag field")
- }
- if field.Type.Kind() != reflect.TypeOf(flag(0)).Kind() {
- panic("reflect.Value flag field has changed kind")
- }
- type t0 int
- var t struct {
- A t0
- // t0 will have flagEmbedRO set.
- t0
- // a will have flagStickyRO set
- a t0
- }
- vA := reflect.ValueOf(t).FieldByName("A")
- va := reflect.ValueOf(t).FieldByName("a")
- vt0 := reflect.ValueOf(t).FieldByName("t0")
-
- // Infer flagRO from the difference between the flags
- // for the (otherwise identical) fields in t.
- flagPublic := *flagField(&vA)
- flagWithRO := *flagField(&va) | *flagField(&vt0)
- flagRO = flagPublic ^ flagWithRO
-
- // Infer flagAddr from the difference between a value
- // taken from a pointer and not.
- vPtrA := reflect.ValueOf(&t).Elem().FieldByName("A")
- flagNoPtr := *flagField(&vA)
- flagPtr := *flagField(&vPtrA)
- flagAddr = flagNoPtr ^ flagPtr
-
- // Check that the inferred flags tally with one of the known versions.
- for _, f := range okFlags {
- if flagRO == f.ro && flagAddr == f.addr {
- return
- }
- }
- panic("reflect.Value read-only flag has changed semantics")
-}