audio/internal/convert: bug fix: Read never returned io.EOF when seeked

audio/internal/convert/float32.go

@@ -68,7 +68,11 @@ func (r *float32BytesReader) Read(buf []byte) (int, error) {
 	copy(r.i16Buf, r.i16Buf[samplesToFill*2:])
 	r.i16Buf = r.i16Buf[:len(r.i16Buf)-samplesToFill*2]
 
-	return samplesToFill * 4, nil
+	n := samplesToFill * 4
+	if r.eof {
+		return n, io.EOF
+	}
+	return n, nil
 }
 
 func (r *float32BytesReader) Seek(offset int64, whence int) (int64, error) {

audio/internal/convert/float32_test.go

@@ -66,6 +66,13 @@ func TestFloat32(t *testing.T) {
 	for _, c := range cases {
 		c := c
 		t.Run(c.Name, func(t *testing.T) {
+			for _, seek := range []bool{false, true} {
+				seek := seek
+				name := "nonseek"
+				if seek {
+					name = "seek"
+				}
+				t.Run(name, func(t *testing.T) {
 					// Note that unsafe.SliceData is available as of Go 1.20.
 					var in, out []byte
 					if len(c.In) > 0 {
@@ -76,7 +83,7 @@ func TestFloat32(t *testing.T) {
 						in = unsafe.Slice((*byte)(unsafe.Pointer(&c.In[0])), len(c.In)*2)
 						out = unsafe.Slice((*byte)(unsafe.Pointer(&outF32[0])), len(outF32)*4)
 					}
-			r := convert.NewFloat32BytesReaderFromInt16BytesReader(bytes.NewReader(in))
+					r := convert.NewFloat32BytesReaderFromInt16BytesReader(bytes.NewReader(in)).(io.ReadSeeker)
 					var got []byte
 					for {
 						var buf [97]byte
@@ -88,6 +95,14 @@ func TestFloat32(t *testing.T) {
 							}
 							break
 						}
+						if seek {
+							if _, err := r.Seek(0, io.SeekCurrent); err != nil {
+								if err != io.EOF {
+									t.Fatal(err)
+								}
+								break
+							}
+						}
 					}
 					want := out
 					if !bytes.Equal(got, want) {
@@ -95,4 +110,6 @@ func TestFloat32(t *testing.T) {
 					}
 				})
 			}
+		})
+	}
 }