lib/model: Don't close file early (fixes #6875) (#6876)

lib/model/folder_sendrecv.go

@@ -1317,10 +1317,10 @@ func (f *sendReceiveFolder) copierRoutine(in <-chan copyBlocksState, pullChan ch
 					if err != nil {
 						return false
 					}
+					defer fd.Close()
 
 					srcOffset := int64(state.file.BlockSize()) * int64(index)
 					_, err = fd.ReadAt(buf, srcOffset)
-					fd.Close()
 					if err != nil {
 						return false
 					}

lib/model/folder_sendrecv_test.go

@@ -202,6 +202,8 @@ func TestHandleFileWithTemp(t *testing.T) {
 }
 
 func TestCopierFinder(t *testing.T) {
+	for _, method := range []fs.CopyRangeMethod{fs.CopyRangeMethodStandard, fs.CopyRangeMethodAllWithFallback} {
+		t.Run(method.String(), func(t *testing.T) {
 			// After diff between required and existing we should:
 			// Copy: 1, 2, 3, 4, 6, 7, 8
 			// Since there is no existing file, nor a temp file
@@ -219,6 +221,8 @@ func TestCopierFinder(t *testing.T) {
 			requiredFile.Name = "file2"
 
 			m, f := setupSendReceiveFolder(existingFile)
+			f.CopyRangeMethod = method
+
 			defer cleanupSRFolder(f, m)
 
 			if _, err := prepareTmpFile(f.Filesystem()); err != nil {
@@ -291,6 +295,8 @@ func TestCopierFinder(t *testing.T) {
 					t.Errorf("Block %d mismatch: %s != %s", eq, blks[eq-1].String(), blocks[eq].String())
 				}
 			}
+		})
+	}
 }
 
 func TestWeakHash(t *testing.T) {