From 3a04b86cbb26e9000068cd21698a88b603f50739 Mon Sep 17 00:00:00 2001
From: Donghyun Kim <temeddix@gmail.com>
Date: Sun, 29 Sep 2024 22:46:50 +0900
Subject: [PATCH] Organize error code

---
 .../example/native/sample_crate/src/error.rs  | 25 +++++++++++++------
 .../native/sample_crate/src/fractal.rs        |  2 +-
 .../example/native/sample_crate/src/lib.rs    |  6 ++---
 rust_crate/src/error.rs                       | 12 ++++-----
 4 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/flutter_package/example/native/sample_crate/src/error.rs b/flutter_package/example/native/sample_crate/src/error.rs
index 94fd4ff8..6eb7dae6 100644
--- a/flutter_package/example/native/sample_crate/src/error.rs
+++ b/flutter_package/example/native/sample_crate/src/error.rs
@@ -2,17 +2,26 @@ use std::error::Error;
 use std::fmt;
 
 #[derive(Debug)]
-pub struct ExampleError(pub Box<dyn Error + Send + Sync>);
+pub enum ExampleError {
+    Fractal,
+    HardwareId,
+    WebApi,
+}
 
 impl fmt::Display for ExampleError {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let source = self.0.as_ref();
-        write!(f, "An error occured inside the example code.\n{source}")
+        match self {
+            Self::Fractal => {
+                write!(f, "Failed to generate fractal")
+            }
+            Self::HardwareId => {
+                write!(f, "Unable to retrieve hardware ID")
+            }
+            Self::WebApi => {
+                write!(f, "Web API call failed")
+            }
+        }
     }
 }
 
-impl Error for ExampleError {
-    fn source(&self) -> Option<&(dyn Error + 'static)> {
-        Some(self.0.as_ref())
-    }
-}
+impl Error for ExampleError {}
diff --git a/flutter_package/example/native/sample_crate/src/fractal.rs b/flutter_package/example/native/sample_crate/src/fractal.rs
index 12ad1423..0b52b8c2 100644
--- a/flutter_package/example/native/sample_crate/src/fractal.rs
+++ b/flutter_package/example/native/sample_crate/src/fractal.rs
@@ -29,7 +29,7 @@ pub fn draw_fractal_image(scale: f64) -> Result<Vec<u8>, ExampleError> {
 
     match result {
         Ok(_) => Ok(image_data),
-        Err(error) => Err(ExampleError(error.into())),
+        Err(_) => Err(ExampleError::Fractal),
     }
 }
 
diff --git a/flutter_package/example/native/sample_crate/src/lib.rs b/flutter_package/example/native/sample_crate/src/lib.rs
index dd1af987..ef5b3fd9 100644
--- a/flutter_package/example/native/sample_crate/src/lib.rs
+++ b/flutter_package/example/native/sample_crate/src/lib.rs
@@ -17,7 +17,7 @@ pub fn get_hardward_id() -> Result<String, ExampleError> {
         .add_component(machineid_rs::HWIDComponent::CPUCores);
     let hwid = builder
         .build("mykey")
-        .map_err(|error| ExampleError(error.into()))?;
+        .map_err(|_| ExampleError::HardwareId)?;
     Ok(hwid)
 }
 #[cfg(not(any(
@@ -39,9 +39,9 @@ pub fn get_current_time() -> DateTime<offset::Local> {
 pub async fn fetch_from_web_api(url: &str) -> Result<String, ExampleError> {
     let fetched = reqwest::get(url)
         .await
-        .map_err(|error| ExampleError(error.into()))?
+        .map_err(|_| ExampleError::WebApi)?
         .text()
         .await
-        .map_err(|error| ExampleError(error.into()))?;
+        .map_err(|_| ExampleError::WebApi)?;
     Ok(fetched)
 }
diff --git a/rust_crate/src/error.rs b/rust_crate/src/error.rs
index 489c8f86..14754371 100644
--- a/rust_crate/src/error.rs
+++ b/rust_crate/src/error.rs
@@ -11,14 +11,14 @@ pub enum RinfError {
 impl fmt::Display for RinfError {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
-            RinfError::NoDartIsolate => {
-                write!(f, "Dart isolate for Rust signals was not created.")
+            Self::NoDartIsolate => {
+                write!(f, "Dart isolate for Rust signals was not created")
             }
-            RinfError::CannotDecodeMessage => {
-                write!(f, "Could not decode the message.")
+            Self::CannotDecodeMessage => {
+                write!(f, "Could not decode the message")
             }
-            RinfError::NoSignalHandler => {
-                write!(f, "Could not find the handler for Dart signal.")
+            Self::NoSignalHandler => {
+                write!(f, "Could not find the handler for Dart signal")
             }
         }
     }