| // Copyright 2012 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 strings_test |
| |
| import ( |
| "os" |
| "strings" |
| "testing" |
| ) |
| |
| func TestReader(t *testing.T) { |
| r := strings.NewReader("0123456789") |
| tests := []struct { |
| off int64 |
| seek int |
| n int |
| want string |
| wantpos int64 |
| seekerr string |
| }{ |
| {seek: os.SEEK_SET, off: 0, n: 20, want: "0123456789"}, |
| {seek: os.SEEK_SET, off: 1, n: 1, want: "1"}, |
| {seek: os.SEEK_CUR, off: 1, wantpos: 3, n: 2, want: "34"}, |
| {seek: os.SEEK_SET, off: -1, seekerr: "strings: negative position"}, |
| {seek: os.SEEK_SET, off: 1<<31 - 1}, |
| {seek: os.SEEK_CUR, off: 1, seekerr: "strings: position out of range"}, |
| {seek: os.SEEK_SET, n: 5, want: "01234"}, |
| {seek: os.SEEK_CUR, n: 5, want: "56789"}, |
| {seek: os.SEEK_END, off: -1, n: 1, wantpos: 9, want: "9"}, |
| } |
| |
| for i, tt := range tests { |
| pos, err := r.Seek(tt.off, tt.seek) |
| if err == nil && tt.seekerr != "" { |
| t.Errorf("%d. want seek error %q", i, tt.seekerr) |
| continue |
| } |
| if err != nil && err.Error() != tt.seekerr { |
| t.Errorf("%d. seek error = %q; want %q", i, err.Error(), tt.seekerr) |
| continue |
| } |
| if tt.wantpos != 0 && tt.wantpos != pos { |
| t.Errorf("%d. pos = %d, want %d", i, pos, tt.wantpos) |
| } |
| buf := make([]byte, tt.n) |
| n, err := r.Read(buf) |
| if err != nil { |
| t.Errorf("%d. read = %v", i, err) |
| continue |
| } |
| got := string(buf[:n]) |
| if got != tt.want { |
| t.Errorf("%d. got %q; want %q", i, got, tt.want) |
| } |
| } |
| } |