various: nicer error handling

Signed-off-by: NotAShelf <raf@notashelf.dev>
Change-Id: Ib6f474603196a32df6e9745e74d0744f6a6a6964

eh/src/util.rs

@@ -70,10 +70,9 @@ impl NixFileFixer for DefaultNixFileFixer {
             .collect();
 
         if files.is_empty() {
-            Err(EhError::NoNixFilesFound)
-        } else {
-            Ok(files)
+            return Err(EhError::NoNixFilesFound);
         }
+        Ok(files)
     }
 
     fn fix_hash_in_file(&self, file_path: &Path, new_hash: &str) -> Result<bool> {
@@ -275,7 +274,9 @@ pub fn handle_nix_with_retry(
     }
 
     // Otherwise, show the error and return error
-    std::io::stderr().write_all(&output.stderr)?;
+    std::io::stderr()
+        .write_all(&output.stderr)
+        .map_err(EhError::Io)?;
     Err(EhError::ProcessExit {
         code: output.status.code().unwrap_or(1),
     })

xtask/src/main.rs

@@ -97,15 +97,7 @@ fn create_multicall_binaries(
             fs::remove_file(&target_path)?;
         }
 
-        match fs::hard_link(main_binary, &target_path) {
-            Ok(()) => {
-                println!(
-                    "  created hardlink: {} points to {}",
-                    target_path.display(),
-                    main_binary.display(),
-                );
-            }
-            Err(e) => {
+        if let Err(e) = fs::hard_link(main_binary, &target_path) {
             eprintln!(
                 "  warning: could not create hardlink for {}: {e}",
                 binary.name(),
@@ -123,7 +115,12 @@ fn create_multicall_binaries(
             }
 
             println!("  created copy: {}", target_path.display());
-            }
+        } else {
+            println!(
+                "  created hardlink: {} points to {}",
+                target_path.display(),
+                main_binary.display(),
+            );
         }
     }