io: add tests for SectionReader ReadAt and Size

R=golang-codereviews, dave
CC=golang-codereviews
https://golang.org/cl/39200045

diff --git a/src/pkg/io/io_test.go b/src/pkg/io/io_test.go
index bd7a82f17b63c335bb27aaa1df80a8e29ba1f221..57db1fbf0bfdd51384eaf0b82e13a04e5599afab 100644 (file)
--- a/src/pkg/io/io_test.go
+++ b/src/pkg/io/io_test.go
@@ -281,6 +281,8 @@ func TestSectionReader_ReadAt(t *testing.T) {
                {data: dat, off: 3, n: len(dat), bufLen: len(dat) / 2, at: 2, exp: dat[5 : 5+len(dat)/2], err: nil},
                {data: dat, off: 3, n: len(dat) / 2, bufLen: len(dat)/2 - 2, at: 2, exp: dat[5 : 5+len(dat)/2-2], err: nil},
                {data: dat, off: 3, n: len(dat) / 2, bufLen: len(dat)/2 + 2, at: 2, exp: dat[5 : 5+len(dat)/2-2], err: EOF},
+               {data: dat, off: 0, n: 0, bufLen: 0, at: -1, exp: "", err: EOF},
+               {data: dat, off: 0, n: 0, bufLen: 0, at: 1, exp: "", err: EOF},
        }
        for i, tt := range tests {
                r := strings.NewReader(tt.data)
@@ -319,3 +321,21 @@ func TestSectionReader_Seek(t *testing.T) {
                t.Errorf("Read = %v, %v; want 0, EOF", n, err)
        }
 }
+
+func TestSectionReader_Size(t *testing.T) {
+       tests := []struct {
+               data string
+               want int64
+       }{
+               {"a long sample data, 1234567890", 30},
+               {"", 0},
+       }
+
+       for _, tt := range tests {
+               r := strings.NewReader(tt.data)
+               sr := NewSectionReader(r, 0, int64(len(tt.data)))
+               if got := sr.Size(); got != tt.want {
+                       t.Errorf("Size = %v; want %v", got, tt.want)
+               }
+       }
+}