From fb3e35624b30d9380bd24b339495efccee00688c Mon Sep 17 00:00:00 2001
From: Jiahao XU <Jiahao_XU@outlook.com>
Date: Thu, 21 Jul 2022 19:59:36 +1000
Subject: [PATCH] Fix err handling in `Crates2Json::append_to_path`

Only uses `Self::default()` if the file is not found.

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>
---
 src/metafiles/v2.rs | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/metafiles/v2.rs b/src/metafiles/v2.rs
index 1501e238..3be0ead6 100644
--- a/src/metafiles/v2.rs
+++ b/src/metafiles/v2.rs
@@ -1,6 +1,6 @@
 use std::{
     collections::{BTreeMap, BTreeSet},
-    fs,
+    fs, io,
     path::{Path, PathBuf},
 };
 
@@ -69,7 +69,13 @@ impl Crates2Json {
         cvs: CrateVersionSource,
         info: CrateInfo,
     ) -> Result<(), Crates2JsonParseError> {
-        let mut c2 = Self::load_from_path(path.as_ref()).unwrap_or_default();
+        let mut c2 = match Self::load_from_path(path.as_ref()) {
+            Ok(c2) => c2,
+            Err(Crates2JsonParseError::Io(io_err)) if io_err.kind() == io::ErrorKind::NotFound => {
+                Self::default()
+            }
+            Err(err) => return Err(err),
+        };
         c2.insert(cvs, info);
         c2.write_to_path(path.as_ref())?;
 
@@ -84,7 +90,7 @@ impl Crates2Json {
 #[derive(Debug, Diagnostic, Error)]
 pub enum Crates2JsonParseError {
     #[error(transparent)]
-    Io(#[from] std::io::Error),
+    Io(#[from] io::Error),
 
     #[error(transparent)]
     Json(#[from] serde_json::Error),