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// run
// Copyright 2013 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 main
// Concrete types implementing M method.
// Smaller than a word, word-sized, larger than a word.
// Value and pointer receivers.
type Tinter interface {
M(int, byte) (byte, int)
}
type Tsmallv byte
func (v Tsmallv) M(x int, b byte) (byte, int) { return b, x+int(v) }
type Tsmallp byte
func (p *Tsmallp) M(x int, b byte) (byte, int) { return b, x+int(*p) }
type Twordv uintptr
func (v Twordv) M(x int, b byte) (byte, int) { return b, x+int(v) }
type Twordp uintptr
func (p *Twordp) M(x int, b byte) (byte, int) { return b, x+int(*p) }
type Tbigv [2]uintptr
func (v Tbigv) M(x int, b byte) (byte, int) { return b, x+int(v[0])+int(v[1]) }
type Tbigp [2]uintptr
func (p *Tbigp) M(x int, b byte) (byte, int) { return b, x+int(p[0])+int(p[1]) }
// Again, with an unexported method.
type tsmallv byte
func (v tsmallv) m(x int, b byte) (byte, int) { return b, x+int(v) }
type tsmallp byte
func (p *tsmallp) m(x int, b byte) (byte, int) { return b, x+int(*p) }
type twordv uintptr
func (v twordv) m(x int, b byte) (byte, int) { return b, x+int(v) }
type twordp uintptr
func (p *twordp) m(x int, b byte) (byte, int) { return b, x+int(*p) }
type tbigv [2]uintptr
func (v tbigv) m(x int, b byte) (byte, int) { return b, x+int(v[0])+int(v[1]) }
type tbigp [2]uintptr
func (p *tbigp) m(x int, b byte) (byte, int) { return b, x+int(p[0])+int(p[1]) }
type tinter interface {
m(int, byte) (byte, int)
}
// Embedding via pointer.
type T1 struct {
T2
}
type T2 struct {
*T3
}
type T3 struct {
*T4
}
type T4 struct {
}
func (t4 T4) M(x int, b byte) (byte, int) { return b, x+40 }
var failed = false
func CheckI(name string, i Tinter, inc int) {
b, x := i.M(1000, 99)
if b != 99 || x != 1000+inc {
failed = true
print(name, ".M(1000, 99) = ", b, ", ", x, " want 99, ", 1000+inc, "\n")
}
CheckF("(i="+name+")", i.M, inc)
}
func CheckF(name string, f func(int, byte) (byte, int), inc int) {
b, x := f(1000, 99)
if b != 99 || x != 1000+inc {
failed = true
print(name, "(1000, 99) = ", b, ", ", x, " want 99, ", 1000+inc, "\n")
}
}
func checkI(name string, i tinter, inc int) {
b, x := i.m(1000, 99)
if b != 99 || x != 1000+inc {
failed = true
print(name, ".m(1000, 99) = ", b, ", ", x, " want 99, ", 1000+inc, "\n")
}
checkF("(i="+name+")", i.m, inc)
}
func checkF(name string, f func(int, byte) (byte, int), inc int) {
b, x := f(1000, 99)
if b != 99 || x != 1000+inc {
failed = true
print(name, "(1000, 99) = ", b, ", ", x, " want 99, ", 1000+inc, "\n")
}
}
func shouldPanic(f func()) {
defer func() {
if recover() == nil {
panic("not panicking")
}
}()
f()
}
func shouldNotPanic(f func()) {
f()
}
func main() {
sv := Tsmallv(1)
CheckI("sv", sv, 1)
CheckF("sv.M", sv.M, 1)
CheckF("(&sv).M", (&sv).M, 1)
psv := &sv
CheckI("psv", psv, 1)
CheckF("psv.M", psv.M, 1)
CheckF("(*psv).M", (*psv).M, 1)
sp := Tsmallp(2)
CheckI("&sp", &sp, 2)
CheckF("sp.M", sp.M, 2)
CheckF("(&sp).M", (&sp).M, 2)
psp := &sp
CheckI("psp", psp, 2)
CheckF("psp.M", psp.M, 2)
CheckF("(*psp).M", (*psp).M, 2)
wv := Twordv(3)
CheckI("wv", wv, 3)
CheckF("wv.M", wv.M, 3)
CheckF("(&wv).M", (&wv).M, 3)
pwv := &wv
CheckI("pwv", pwv, 3)
CheckF("pwv.M", pwv.M, 3)
CheckF("(*pwv).M", (*pwv).M, 3)
wp := Twordp(4)
CheckI("&wp", &wp, 4)
CheckF("wp.M", wp.M, 4)
CheckF("(&wp).M", (&wp).M, 4)
pwp := &wp
CheckI("pwp", pwp, 4)
CheckF("pwp.M", pwp.M, 4)
CheckF("(*pwp).M", (*pwp).M, 4)
bv := Tbigv([2]uintptr{5, 6})
pbv := &bv
CheckI("bv", bv, 11)
CheckF("bv.M", bv.M, 11)
CheckF("(&bv).M", (&bv).M, 11)
CheckI("pbv", pbv, 11)
CheckF("pbv.M", pbv.M, 11)
CheckF("(*pbv).M", (*pbv).M, 11)
bp := Tbigp([2]uintptr{7,8})
CheckI("&bp", &bp, 15)
CheckF("bp.M", bp.M, 15)
CheckF("(&bp).M", (&bp).M, 15)
pbp := &bp
CheckI("pbp", pbp, 15)
CheckF("pbp.M", pbp.M, 15)
CheckF("(*pbp).M", (*pbp).M, 15)
_sv := tsmallv(1)
checkI("_sv", _sv, 1)
checkF("_sv.m", _sv.m, 1)
checkF("(&_sv).m", (&_sv).m, 1)
_psv := &_sv
checkI("_psv", _psv, 1)
checkF("_psv.m", _psv.m, 1)
checkF("(*_psv).m", (*_psv).m, 1)
_sp := tsmallp(2)
checkI("&_sp", &_sp, 2)
checkF("_sp.m", _sp.m, 2)
checkF("(&_sp).m", (&_sp).m, 2)
_psp := &_sp
checkI("_psp", _psp, 2)
checkF("_psp.m", _psp.m, 2)
checkF("(*_psp).m", (*_psp).m, 2)
_wv := twordv(3)
checkI("_wv", _wv, 3)
checkF("_wv.m", _wv.m, 3)
checkF("(&_wv).m", (&_wv).m, 3)
_pwv := &_wv
checkI("_pwv", _pwv, 3)
checkF("_pwv.m", _pwv.m, 3)
checkF("(*_pwv).m", (*_pwv).m, 3)
_wp := twordp(4)
checkI("&_wp", &_wp, 4)
checkF("_wp.m", _wp.m, 4)
checkF("(&_wp).m", (&_wp).m, 4)
_pwp := &_wp
checkI("_pwp", _pwp, 4)
checkF("_pwp.m", _pwp.m, 4)
checkF("(*_pwp).m", (*_pwp).m, 4)
_bv := tbigv([2]uintptr{5, 6})
_pbv := &_bv
checkI("_bv", _bv, 11)
checkF("_bv.m", _bv.m, 11)
checkF("(&_bv).m", (&_bv).m, 11)
checkI("_pbv", _pbv, 11)
checkF("_pbv.m", _pbv.m, 11)
checkF("(*_pbv).m", (*_pbv).m, 11)
_bp := tbigp([2]uintptr{7,8})
checkI("&_bp", &_bp, 15)
checkF("_bp.m", _bp.m, 15)
checkF("(&_bp).m", (&_bp).m, 15)
_pbp := &_bp
checkI("_pbp", _pbp, 15)
checkF("_pbp.m", _pbp.m, 15)
checkF("(*_pbp).m", (*_pbp).m, 15)
t4 := T4{}
t3 := T3{&t4}
t2 := T2{&t3}
t1 := T1{t2}
CheckI("t4", t4, 40)
CheckI("&t4", &t4, 40)
CheckI("t3", t3, 40)
CheckI("&t3", &t3, 40)
CheckI("t2", t2, 40)
CheckI("&t2", &t2, 40)
CheckI("t1", t1, 40)
CheckI("&t1", &t1, 40)
// x.M panics if x is an interface type and is nil,
// or if x.M expands to (*x).M where x is nil,
// or if x.M expands to x.y.z.w.M where something
// along the evaluation of x.y.z.w is nil.
var f func(int, byte) (byte, int)
shouldPanic(func() { psv = nil; f = psv.M })
shouldPanic(func() { pwv = nil; f = pwv.M })
shouldPanic(func() { pbv = nil; f = pbv.M })
shouldPanic(func() { var i Tinter; f = i.M })
shouldPanic(func() { _psv = nil; f = _psv.m })
shouldPanic(func() { _pwv = nil; f = _pwv.m })
shouldPanic(func() { _pbv = nil; f = _pbv.m })
shouldPanic(func() { var _i tinter; f = _i.m })
shouldPanic(func() { var t1 T1; f = t1.M })
shouldPanic(func() { var t2 T2; f = t2.M })
shouldPanic(func() { var t3 *T3; f = t3.M })
shouldPanic(func() { var t3 T3; f = t3.M })
if f != nil {
panic("something set f")
}
// x.M does not panic if x is a nil pointer and
// M is a method with a pointer receiver.
shouldNotPanic(func() { psp = nil; f = psp.M })
shouldNotPanic(func() { pwp = nil; f = pwp.M })
shouldNotPanic(func() { pbp = nil; f = pbp.M })
shouldNotPanic(func() { _psp = nil; f = _psp.m })
shouldNotPanic(func() { _pwp = nil; f = _pwp.m })
shouldNotPanic(func() { _pbp = nil; f = _pbp.m })
shouldNotPanic(func() { var t4 T4; f = t4.M })
if f == nil {
panic("nothing set f")
}
}
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