github.com/megatontech/mynoteforgo@v0.0.0-20200507084910-5d0c6ea6e890/源码/runtime/sizeof_test.go (about)

     1  // Copyright 2018 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // +build !nacl
     6  
     7  package runtime_test
     8  
     9  import (
    10  	"reflect"
    11  	"runtime"
    12  	"testing"
    13  	"unsafe"
    14  )
    15  
    16  // Assert that the size of important structures do not change unexpectedly.
    17  
    18  func TestSizeof(t *testing.T) {
    19  	const _64bit = unsafe.Sizeof(uintptr(0)) == 8
    20  
    21  	var tests = []struct {
    22  		val    interface{} // type as a value
    23  		_32bit uintptr     // size on 32bit platforms
    24  		_64bit uintptr     // size on 64bit platforms
    25  	}{
    26  		{runtime.G{}, 216, 376}, // g, but exported for testing
    27  	}
    28  
    29  	for _, tt := range tests {
    30  		want := tt._32bit
    31  		if _64bit {
    32  			want = tt._64bit
    33  		}
    34  		got := reflect.TypeOf(tt.val).Size()
    35  		if want != got {
    36  			t.Errorf("unsafe.Sizeof(%T) = %d, want %d", tt.val, got, want)
    37  		}
    38  	}
    39  }