Fix #68: Do not write empty content to file (#71)v0.7.3

2 files changed, 20 insertions, 5 deletions

diff --git a/src/input.rs b/src/input.rs
index 28adaf2..8a785d2 100644
--- a/src/input.rs
+++ b/src/input.rs
@@ -113,9 +113,11 @@ impl Replacer {
         file.set_len(replaced.len() as u64)?;
         file.set_permissions(meta.permissions())?;
 
-        let mut mmap_target = unsafe { MmapMut::map_mut(&file)? };
-        mmap_target.deref_mut().write_all(&replaced)?;
-        mmap_target.flush_async()?;
+        if !replaced.is_empty() {
+            let mut mmap_target = unsafe { MmapMut::map_mut(&file)? };
+            mmap_target.deref_mut().write_all(&replaced)?;
+            mmap_target.flush_async()?;
+        }
 
         drop(mmap_source);
         drop(source);
diff --git a/tests/cli.rs b/tests/cli.rs
index 420eca4..7d95411 100644
--- a/tests/cli.rs
+++ b/tests/cli.rs
@@ -25,13 +25,26 @@ fn in_place() -> Result<()> {
 }
 
 #[test]
+fn in_place_with_empty_result_file() -> Result<()> {
+    let mut file = tempfile::NamedTempFile::new()?;
+    file.write(b"a7c")?;
+    let path = file.into_temp_path();
+
+    sd().args(&["a\\dc", "", path.to_str().unwrap()])
+        .assert()
+        .success();
+    assert_file(&path.to_path_buf(), "");
+
+    Ok(())
+}
+
+#[test]
 fn replace_into_stdout() -> Result<()> {
     let mut file = tempfile::NamedTempFile::new()?;
     file.write(b"abc123def")?;
 
     #[rustfmt::skip]
-    sd()
-        .args(&["-p", "abc\\d+", "", file.path().to_str().unwrap()])
+    sd().args(&["-p", "abc\\d+", "", file.path().to_str().unwrap()])
         .assert()
         .success()
         .stdout("def");