From cee2fd07c0edc73735d0a23d935d29777dc55dd2 Mon Sep 17 00:00:00 2001
From: Toshiki Teramura <toshiki.teramura@gmail.com>
Date: Sat, 18 Sep 2021 18:13:19 +0900
Subject: [PATCH] Use openblas_build::error::Error in FromStr of Target #78

---
 openblas-build/src/build.rs | 28 ++++++++++++++++------------
 openblas-build/src/error.rs |  3 +++
 2 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/openblas-build/src/build.rs b/openblas-build/src/build.rs
index 895a83d..58ac95a 100644
--- a/openblas-build/src/build.rs
+++ b/openblas-build/src/build.rs
@@ -2,7 +2,7 @@
 
 use crate::{check::*, error::*};
 use std::{
-    fmt, fs,
+    fs,
     os::unix::io::*,
     path::*,
     process::{Command, Stdio},
@@ -118,7 +118,7 @@ pub enum Target {
 }
 
 impl FromStr for Target {
-    type Err = ParseTargetError;
+    type Err = Error;
 
     fn from_str(s: &str) -> Result<Self, Self::Err> {
         let target = match s.to_ascii_lowercase().as_str() {
@@ -195,21 +195,16 @@ impl FromStr for Target {
             "zarch_generic" => Self::ZARCH_GENERIC,
             "z13" => Self::Z13,
             "z14" => Self::Z14,
-            _ => return Err(ParseTargetError::default()),
+            _ => {
+                return Err(Error::UnsupportedTarget {
+                    target: s.to_string(),
+                })
+            }
         };
         Ok(target)
     }
 }
 
-#[derive(Debug, Clone, PartialEq, Eq, Default)]
-pub struct ParseTargetError;
-
-impl fmt::Display for ParseTargetError {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        "provided string was not a valid target".fmt(f)
-    }
-}
-
 /// make option generator
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct Configure {
@@ -408,6 +403,15 @@ impl Configure {
 mod tests {
     use super::*;
 
+    #[test]
+    fn target_from_str() {
+        assert_eq!(Target::from_str("p2").unwrap(), Target::P2);
+        assert!(matches!(
+            Target::from_str("p3").unwrap_err(),
+            crate::error::Error::UnsupportedTarget { .. }
+        ));
+    }
+
     #[ignore]
     #[test]
     fn build_default() {
diff --git a/openblas-build/src/error.rs b/openblas-build/src/error.rs
index 5823152..e49e9e8 100644
--- a/openblas-build/src/error.rs
+++ b/openblas-build/src/error.rs
@@ -21,6 +21,9 @@ pub enum Error {
     #[error("Library file does not exist: {}", path.display())]
     LibraryNotExist { path: PathBuf },
 
+    #[error("Target {} is unsupported", target)]
+    UnsupportedTarget { target: String },
+
     #[error("Other IO errors: {0:?}")]
     IOError(#[from] io::Error),
 }