1// run
2
3// Copyright 2009 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
7// Test floating-point comparison involving NaN.
8
9package main
10
11import "math"
12
13type floatTest struct {
14	name string
15	expr bool
16	want bool
17}
18
19var nan float64 = math.NaN()
20var f float64 = 1
21
22var tests = []floatTest{
23	floatTest{"nan == nan", nan == nan, false},
24	floatTest{"nan != nan", nan != nan, true},
25	floatTest{"nan < nan", nan < nan, false},
26	floatTest{"nan > nan", nan > nan, false},
27	floatTest{"nan <= nan", nan <= nan, false},
28	floatTest{"nan >= nan", nan >= nan, false},
29	floatTest{"f == nan", f == nan, false},
30	floatTest{"f != nan", f != nan, true},
31	floatTest{"f < nan", f < nan, false},
32	floatTest{"f > nan", f > nan, false},
33	floatTest{"f <= nan", f <= nan, false},
34	floatTest{"f >= nan", f >= nan, false},
35	floatTest{"nan == f", nan == f, false},
36	floatTest{"nan != f", nan != f, true},
37	floatTest{"nan < f", nan < f, false},
38	floatTest{"nan > f", nan > f, false},
39	floatTest{"nan <= f", nan <= f, false},
40	floatTest{"nan >= f", nan >= f, false},
41	floatTest{"!(nan == nan)", !(nan == nan), true},
42	floatTest{"!(nan != nan)", !(nan != nan), false},
43	floatTest{"!(nan < nan)", !(nan < nan), true},
44	floatTest{"!(nan > nan)", !(nan > nan), true},
45	floatTest{"!(nan <= nan)", !(nan <= nan), true},
46	floatTest{"!(nan >= nan)", !(nan >= nan), true},
47	floatTest{"!(f == nan)", !(f == nan), true},
48	floatTest{"!(f != nan)", !(f != nan), false},
49	floatTest{"!(f < nan)", !(f < nan), true},
50	floatTest{"!(f > nan)", !(f > nan), true},
51	floatTest{"!(f <= nan)", !(f <= nan), true},
52	floatTest{"!(f >= nan)", !(f >= nan), true},
53	floatTest{"!(nan == f)", !(nan == f), true},
54	floatTest{"!(nan != f)", !(nan != f), false},
55	floatTest{"!(nan < f)", !(nan < f), true},
56	floatTest{"!(nan > f)", !(nan > f), true},
57	floatTest{"!(nan <= f)", !(nan <= f), true},
58	floatTest{"!(nan >= f)", !(nan >= f), true},
59	floatTest{"!!(nan == nan)", !!(nan == nan), false},
60	floatTest{"!!(nan != nan)", !!(nan != nan), true},
61	floatTest{"!!(nan < nan)", !!(nan < nan), false},
62	floatTest{"!!(nan > nan)", !!(nan > nan), false},
63	floatTest{"!!(nan <= nan)", !!(nan <= nan), false},
64	floatTest{"!!(nan >= nan)", !!(nan >= nan), false},
65	floatTest{"!!(f == nan)", !!(f == nan), false},
66	floatTest{"!!(f != nan)", !!(f != nan), true},
67	floatTest{"!!(f < nan)", !!(f < nan), false},
68	floatTest{"!!(f > nan)", !!(f > nan), false},
69	floatTest{"!!(f <= nan)", !!(f <= nan), false},
70	floatTest{"!!(f >= nan)", !!(f >= nan), false},
71	floatTest{"!!(nan == f)", !!(nan == f), false},
72	floatTest{"!!(nan != f)", !!(nan != f), true},
73	floatTest{"!!(nan < f)", !!(nan < f), false},
74	floatTest{"!!(nan > f)", !!(nan > f), false},
75	floatTest{"!!(nan <= f)", !!(nan <= f), false},
76	floatTest{"!!(nan >= f)", !!(nan >= f), false},
77}
78
79func main() {
80	bad := false
81	for _, t := range tests {
82		if t.expr != t.want {
83			if !bad {
84				bad = true
85				println("BUG: floatcmp")
86			}
87			println(t.name, "=", t.expr, "want", t.want)
88		}
89	}
90	if bad {
91		panic("floatcmp failed")
92	}
93}
94