clippy: Resolve single_match

TEST=bin/clippy

Change-Id: Iea0d3539b3ab587a2d97f676e1d9c7a239504308
Reviewed-on: https://chromium-review.googlesource.com/1566748
Commit-Ready: David Tolnay <dtolnay@chromium.org>
Tested-by: David Tolnay <dtolnay@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>

1 files changed, 4 insertions, 5 deletions

diff --git a/qcow/src/qcow.rs b/qcow/src/qcow.rs
index 52a6cc2..9b301a5 100644
--- a/qcow/src/qcow.rs
+++ b/qcow/src/qcow.rs
@@ -549,13 +549,12 @@ impl QcowFile {
 
         let mut cluster_addr = 0;
         while cluster_addr < file_size {
-            match self
+            let cluster_refcount = self
                 .refcounts
                 .get_cluster_refcount(&mut self.raw_file, cluster_addr)
-                .map_err(Error::GettingRefcount)?
-            {
-                0 => return Ok(Some(cluster_addr)),
-                _ => (),
+                .map_err(Error::GettingRefcount)?;
+            if cluster_refcount == 0 {
+                return Ok(Some(cluster_addr));
             }
             cluster_addr += cluster_size;
         }