From 41ab00deccc687ae9d3ec42cb3009d85c872c352 Mon Sep 17 00:00:00 2001
From: Ryu <114303361+ryuapp@users.noreply.github.com>
Date: Wed, 3 Jun 2026 20:52:46 +0900
Subject: [PATCH] refactor: remove thiserror dependency

---
 Cargo.lock    | 56 ---------------------------------------------------
 Cargo.toml    |  1 -
 src/parser.rs | 19 ++++++++++++-----
 3 files changed, 14 insertions(+), 62 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index eb24bdc..f9eba06 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -8,65 +8,9 @@ version = "1.0.102"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7f202df86484c868dbad7eaa557ef785d5c66295e41b460ef922eca0723b842c"
 
-[[package]]
-name = "proc-macro2"
-version = "1.0.106"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8fd00f0bb2e90d81d1044c2b32617f68fcb9fa3bb7640c23e9c748e53fb30934"
-dependencies = [
- "unicode-ident",
-]
-
-[[package]]
-name = "quote"
-version = "1.0.45"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "41f2619966050689382d2b44f664f4bc593e129785a36d6ee376ddf37259b924"
-dependencies = [
- "proc-macro2",
-]
-
 [[package]]
 name = "rysh"
 version = "0.1.0"
 dependencies = [
  "anyhow",
- "thiserror",
-]
-
-[[package]]
-name = "syn"
-version = "2.0.117"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e665b8803e7b1d2a727f4023456bbbbe74da67099c585258af0ad9c5013b9b99"
-dependencies = [
- "proc-macro2",
- "quote",
- "unicode-ident",
-]
-
-[[package]]
-name = "thiserror"
-version = "2.0.18"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4288b5bcbc7920c07a1149a35cf9590a2aa808e0bc1eafaade0b80947865fbc4"
-dependencies = [
- "thiserror-impl",
-]
-
-[[package]]
-name = "thiserror-impl"
-version = "2.0.18"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ebc4ee7f67670e9b64d05fa4253e753e016c6c95ff35b89b7941d6b856dec1d5"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
 ]
-
-[[package]]
-name = "unicode-ident"
-version = "1.0.24"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e6e4313cd5fcd3dad5cafa179702e2b244f760991f45397d14d4ebf38247da75"
diff --git a/Cargo.toml b/Cargo.toml
index 3ab5a9f..6b17536 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,4 +15,3 @@ path = "src/main.rs"
 
 [dependencies]
 anyhow = "1.0.98"
-thiserror = "2.0.12"
diff --git a/src/parser.rs b/src/parser.rs
index 583e6aa..8c909b8 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -14,14 +14,23 @@ impl Word {
     }
 }
 
-#[derive(Debug, thiserror::Error, PartialEq, Eq)]
+#[derive(Debug, PartialEq, Eq)]
 pub(crate) enum ParseError {
-    #[error("unterminated quote")]
     UnterminatedQuote,
-    #[error("expected command after operator")]
     ExpectedCommand,
-    #[error("expected redirect target")]
     ExpectedRedirectTarget,
-    #[error("unexpected token: {0}")]
     UnexpectedToken(String),
 }
+
+impl std::fmt::Display for ParseError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Self::UnterminatedQuote => write!(f, "unterminated quote"),
+            Self::ExpectedCommand => write!(f, "expected command after operator"),
+            Self::ExpectedRedirectTarget => write!(f, "expected redirect target"),
+            Self::UnexpectedToken(token) => write!(f, "unexpected token: {token}"),
+        }
+    }
+}
+
+impl std::error::Error for ParseError {}