gcc/testsuite/go.test/test/convlit.go

   1 // errchk $G -e $D/$F.go
   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 package main
   8
   9 // explicit conversion of constants is work in progress.
  10 // the ERRORs in this block are debatable, but they're what
  11 // the language spec says for now.
  12 var x1 = string(1)
  13 var x2 string = string(1)
  14 var x3 = int(1.5)       // ERROR "convert|truncate"
  15 var x4 int = int(1.5)   // ERROR "convert|truncate"
  16 var x5 = "a" + string(1)
  17 var x6 = int(1e100)     // ERROR "overflow"
  18 var x7 = float(1e1000)  // ERROR "overflow"
  19
  20 // implicit conversions merit scrutiny
  21 var s string
  22 var bad1 string = 1     // ERROR "conver|incompatible|invalid|cannot"
  23 var bad2 = s + 1                // ERROR "conver|incompatible|invalid"
  24 var bad3 = s + 'a'      // ERROR "conver|incompatible|invalid"
  25 var bad4 = "a" + 1      // ERROR "literals|incompatible|convert|invalid"
  26 var bad5 = "a" + 'a'    // ERROR "literals|incompatible|convert|invalid"
  27
  28 var bad6 int = 1.5      // ERROR "convert|truncate"
  29 var bad7 int = 1e100    // ERROR "overflow"
  30 var bad8 float32 = 1e200        // ERROR "overflow"
  31
  32 // but these implicit conversions are okay
  33 var good1 string = "a"
  34 var good2 int = 1.0
  35 var good3 int = 1e9
  36 var good4 float = 1e20
  37
  38 // explicit conversion of string is okay
  39 var _ = []int("abc")
  40 var _ = []byte("abc")
  41
  42 // implicit is not
  43 var _ []int = "abc"     // ERROR "cannot use|incompatible|invalid"
  44 var _ []byte = "abc"    // ERROR "cannot use|incompatible|invalid"
  45
  46 // named string is okay
  47 type Tstring string
  48 var ss Tstring = "abc"
  49 var _ = []int(ss)
  50 var _ = []byte(ss)
  51
  52 // implicit is still not
  53 var _ []int = ss        // ERROR "cannot use|incompatible|invalid"
  54 var _ []byte = ss       // ERROR "cannot use|incompatible|invalid"
  55
  56 // named slice is not
  57 type Tint []int
  58 type Tbyte []byte
  59 var _ = Tint("abc")     // ERROR "convert|incompatible|invalid"
  60 var _ = Tbyte("abc")    // ERROR "convert|incompatible|invalid"
  61
  62 // implicit is still not
  63 var _ Tint = "abc"      // ERROR "cannot use|incompatible|invalid"
  64 var _ Tbyte = "abc"     // ERROR "cannot use|incompatible|invalid"