1// run
2
3// Copyright 2013 The Go Authors.  All rights reserved.
4// Use of this source code is governed by a BSD-style
5// license that can be found in the LICENSE file.
6
7package main
8
9// Concrete types implementing M method.
10// Smaller than a word, word-sized, larger than a word.
11// Value and pointer receivers.
12
13type Tinter interface {
14	M(int, byte) (byte, int)
15}
16
17type Tsmallv byte
18
19func (v Tsmallv) M(x int, b byte) (byte, int) { return b, x+int(v) }
20
21type Tsmallp byte
22
23func (p *Tsmallp) M(x int, b byte) (byte, int) { return b, x+int(*p) }
24
25type Twordv uintptr
26
27func (v Twordv) M(x int, b byte) (byte, int) { return b, x+int(v) }
28
29type Twordp uintptr
30
31func (p *Twordp) M(x int, b byte) (byte, int) { return b, x+int(*p) }
32
33type Tbigv [2]uintptr
34
35func (v Tbigv) M(x int, b byte) (byte, int) { return b, x+int(v[0])+int(v[1]) }
36
37type Tbigp [2]uintptr
38
39func (p *Tbigp) M(x int, b byte) (byte, int) { return b, x+int(p[0])+int(p[1]) }
40
41// Again, with an unexported method.
42
43type tsmallv byte
44
45func (v tsmallv) m(x int, b byte) (byte, int) { return b, x+int(v) }
46
47type tsmallp byte
48
49func (p *tsmallp) m(x int, b byte) (byte, int) { return b, x+int(*p) }
50
51type twordv uintptr
52
53func (v twordv) m(x int, b byte) (byte, int) { return b, x+int(v) }
54
55type twordp uintptr
56
57func (p *twordp) m(x int, b byte) (byte, int) { return b, x+int(*p) }
58
59type tbigv [2]uintptr
60
61func (v tbigv) m(x int, b byte) (byte, int) { return b, x+int(v[0])+int(v[1]) }
62
63type tbigp [2]uintptr
64
65func (p *tbigp) m(x int, b byte) (byte, int) { return b, x+int(p[0])+int(p[1]) }
66
67type tinter interface {
68	m(int, byte) (byte, int)
69}
70
71// Embedding via pointer.
72
73type T1 struct {
74	T2
75}
76
77type T2 struct {
78	*T3
79}
80
81type T3 struct {
82	*T4
83}
84
85type T4 struct {
86}
87
88func (t4 T4) M(x int, b byte) (byte, int) { return b, x+40 }
89
90var failed = false
91
92func CheckI(name string, i Tinter, inc int) {
93	b, x := i.M(1000, 99)
94	if b != 99 || x != 1000+inc {
95		failed = true
96		print(name, ".M(1000, 99) = ", b, ", ", x, " want 99, ", 1000+inc, "\n")
97	}
98
99	CheckF("(i="+name+")", i.M, inc)
100}
101
102func CheckF(name string, f func(int, byte) (byte, int), inc int) {
103	b, x := f(1000, 99)
104	if b != 99 || x != 1000+inc {
105		failed = true
106		print(name, "(1000, 99) = ", b, ", ", x, " want 99, ", 1000+inc, "\n")
107	}
108}
109
110func checkI(name string, i tinter, inc int) {
111	b, x := i.m(1000, 99)
112	if b != 99 || x != 1000+inc {
113		failed = true
114		print(name, ".m(1000, 99) = ", b, ", ", x, " want 99, ", 1000+inc, "\n")
115	}
116
117	checkF("(i="+name+")", i.m, inc)
118}
119
120func checkF(name string, f func(int, byte) (byte, int), inc int) {
121	b, x := f(1000, 99)
122	if b != 99 || x != 1000+inc {
123		failed = true
124		print(name, "(1000, 99) = ", b, ", ", x, " want 99, ", 1000+inc, "\n")
125	}
126}
127
128func shouldPanic(f func()) {
129	defer func() {
130		if recover() == nil {
131			panic("not panicking")
132		}
133	}()
134	f()
135}
136
137func shouldNotPanic(f func()) {
138	f()
139}
140
141func main() {
142	sv := Tsmallv(1)
143	CheckI("sv", sv, 1)
144	CheckF("sv.M", sv.M, 1)
145	CheckF("(&sv).M", (&sv).M, 1)
146	psv := &sv
147	CheckI("psv", psv, 1)
148	CheckF("psv.M", psv.M, 1)
149	CheckF("(*psv).M", (*psv).M, 1)
150
151	sp := Tsmallp(2)
152	CheckI("&sp", &sp, 2)
153	CheckF("sp.M", sp.M, 2)
154	CheckF("(&sp).M", (&sp).M, 2)
155	psp := &sp
156	CheckI("psp", psp, 2)
157	CheckF("psp.M", psp.M, 2)
158	CheckF("(*psp).M", (*psp).M, 2)
159
160	wv := Twordv(3)
161	CheckI("wv", wv, 3)
162	CheckF("wv.M", wv.M, 3)
163	CheckF("(&wv).M", (&wv).M, 3)
164	pwv := &wv
165	CheckI("pwv", pwv, 3)
166	CheckF("pwv.M", pwv.M, 3)
167	CheckF("(*pwv).M", (*pwv).M, 3)
168
169	wp := Twordp(4)
170	CheckI("&wp", &wp, 4)
171	CheckF("wp.M", wp.M, 4)
172	CheckF("(&wp).M", (&wp).M, 4)
173	pwp := &wp
174	CheckI("pwp", pwp, 4)
175	CheckF("pwp.M", pwp.M, 4)
176	CheckF("(*pwp).M", (*pwp).M, 4)
177
178	bv := Tbigv([2]uintptr{5, 6})
179	pbv := &bv
180	CheckI("bv", bv, 11)
181	CheckF("bv.M", bv.M, 11)
182	CheckF("(&bv).M", (&bv).M, 11)
183	CheckI("pbv", pbv, 11)
184	CheckF("pbv.M", pbv.M, 11)
185	CheckF("(*pbv).M", (*pbv).M, 11)
186
187	bp := Tbigp([2]uintptr{7,8})
188	CheckI("&bp", &bp, 15)
189	CheckF("bp.M", bp.M, 15)
190	CheckF("(&bp).M", (&bp).M, 15)
191	pbp := &bp
192	CheckI("pbp", pbp, 15)
193	CheckF("pbp.M", pbp.M, 15)
194	CheckF("(*pbp).M", (*pbp).M, 15)
195
196	_sv := tsmallv(1)
197	checkI("_sv", _sv, 1)
198	checkF("_sv.m", _sv.m, 1)
199	checkF("(&_sv).m", (&_sv).m, 1)
200	_psv := &_sv
201	checkI("_psv", _psv, 1)
202	checkF("_psv.m", _psv.m, 1)
203	checkF("(*_psv).m", (*_psv).m, 1)
204
205	_sp := tsmallp(2)
206	checkI("&_sp", &_sp, 2)
207	checkF("_sp.m", _sp.m, 2)
208	checkF("(&_sp).m", (&_sp).m, 2)
209	_psp := &_sp
210	checkI("_psp", _psp, 2)
211	checkF("_psp.m", _psp.m, 2)
212	checkF("(*_psp).m", (*_psp).m, 2)
213
214	_wv := twordv(3)
215	checkI("_wv", _wv, 3)
216	checkF("_wv.m", _wv.m, 3)
217	checkF("(&_wv).m", (&_wv).m, 3)
218	_pwv := &_wv
219	checkI("_pwv", _pwv, 3)
220	checkF("_pwv.m", _pwv.m, 3)
221	checkF("(*_pwv).m", (*_pwv).m, 3)
222
223	_wp := twordp(4)
224	checkI("&_wp", &_wp, 4)
225	checkF("_wp.m", _wp.m, 4)
226	checkF("(&_wp).m", (&_wp).m, 4)
227	_pwp := &_wp
228	checkI("_pwp", _pwp, 4)
229	checkF("_pwp.m", _pwp.m, 4)
230	checkF("(*_pwp).m", (*_pwp).m, 4)
231
232	_bv := tbigv([2]uintptr{5, 6})
233	_pbv := &_bv
234	checkI("_bv", _bv, 11)
235	checkF("_bv.m", _bv.m, 11)
236	checkF("(&_bv).m", (&_bv).m, 11)
237	checkI("_pbv", _pbv, 11)
238	checkF("_pbv.m", _pbv.m, 11)
239	checkF("(*_pbv).m", (*_pbv).m, 11)
240
241	_bp := tbigp([2]uintptr{7,8})
242	checkI("&_bp", &_bp, 15)
243	checkF("_bp.m", _bp.m, 15)
244	checkF("(&_bp).m", (&_bp).m, 15)
245	_pbp := &_bp
246	checkI("_pbp", _pbp, 15)
247	checkF("_pbp.m", _pbp.m, 15)
248	checkF("(*_pbp).m", (*_pbp).m, 15)
249
250	t4 := T4{}
251	t3 := T3{&t4}
252	t2 := T2{&t3}
253	t1 := T1{t2}
254	CheckI("t4", t4, 40)
255	CheckI("&t4", &t4, 40)
256	CheckI("t3", t3, 40)
257	CheckI("&t3", &t3, 40)
258	CheckI("t2", t2, 40)
259	CheckI("&t2", &t2, 40)
260	CheckI("t1", t1, 40)
261	CheckI("&t1", &t1, 40)
262
263	// x.M panics if x is an interface type and is nil,
264	// or if x.M expands to (*x).M where x is nil,
265	// or if x.M expands to x.y.z.w.M where something
266	// along the evaluation of x.y.z.w is nil.
267	var f func(int, byte) (byte, int)
268	shouldPanic(func() { psv = nil; f = psv.M })
269	shouldPanic(func() { pwv = nil; f = pwv.M })
270	shouldPanic(func() { pbv = nil; f = pbv.M })
271	shouldPanic(func() { var i Tinter; f = i.M })
272	shouldPanic(func() { _psv = nil; f = _psv.m })
273	shouldPanic(func() { _pwv = nil; f = _pwv.m })
274	shouldPanic(func() { _pbv = nil; f = _pbv.m })
275	shouldPanic(func() { var _i tinter; f = _i.m })
276	shouldPanic(func() { var t1 T1; f = t1.M })
277	shouldPanic(func() { var t2 T2; f = t2.M })
278	shouldPanic(func() { var t3 *T3; f = t3.M })
279	shouldPanic(func() { var t3 T3; f = t3.M })
280
281	if f != nil {
282		panic("something set f")
283	}
284
285	// x.M does not panic if x is a nil pointer and
286	// M is a method with a pointer receiver.
287	shouldNotPanic(func() { psp = nil; f = psp.M })
288	shouldNotPanic(func() { pwp = nil; f = pwp.M })
289	shouldNotPanic(func() { pbp = nil; f = pbp.M })
290	shouldNotPanic(func() { _psp = nil; f = _psp.m })
291	shouldNotPanic(func() { _pwp = nil; f = _pwp.m })
292	shouldNotPanic(func() { _pbp = nil; f = _pbp.m })
293	shouldNotPanic(func() { var t4 T4; f = t4.M })
294	if f == nil {
295		panic("nothing set f")
296	}
297}
298