From d82cb7e5d1822c7cf01b14e463e7270dd33f1218 Mon Sep 17 00:00:00 2001
From: Nick Mathewson <nickm@torproject.org>
Date: Fri, 15 May 2020 08:47:32 -0400
Subject: [PATCH] netdoc: remove ArgError.

---
 tor-netdoc/src/argtype.rs    | 54 ++++++++++++------------------------
 tor-netdoc/src/routerdesc.rs | 13 ++++-----
 2 files changed, 23 insertions(+), 44 deletions(-)

diff --git a/tor-netdoc/src/argtype.rs b/tor-netdoc/src/argtype.rs
index 5d80b162e..03bacfe0b 100644
--- a/tor-netdoc/src/argtype.rs
+++ b/tor-netdoc/src/argtype.rs
@@ -9,35 +9,17 @@ pub use b64impl::*;
 pub use curve25519impl::*;
 pub use timeimpl::*;
 
-use thiserror::Error;
-
-/// A problem that can occur when parsing an argument.
-#[derive(Error, Debug)]
-#[non_exhaustive]
-pub enum ArgError {
-    /// Invalid base64.
-    #[error("bad base64 encoding: {0}")]
-    Base64(#[from] base64::DecodeError),
-    /// A time that was in the wrong form, or out of range.
-    #[error("invalid time: {0}")]
-    BadTime(#[from] chrono::ParseError),
-    /// Some other error, represented as a string.
-    #[error("{0}")]
-    Generic(&'static str),
-}
-
 mod b64impl {
-
-    use super::ArgError;
+    use crate::{Error, Pos, Result};
 
     pub struct B64(Vec<u8>);
 
     impl std::str::FromStr for B64 {
-        type Err = ArgError;
-        fn from_str(s: &str) -> Result<Self, ArgError> {
-            Ok(B64(
-                base64::decode_config(s, base64::STANDARD_NO_PAD).map_err(ArgError::Base64)?
-            ))
+        type Err = Error;
+        fn from_str(s: &str) -> Result<Self> {
+            let bytes = base64::decode_config(s, base64::STANDARD_NO_PAD)
+                .map_err(|e| Error::BadArgument(0, Pos::at(s), format!("Invalid base64: {}", e)))?;
+            Ok(B64(bytes))
         }
     }
 
@@ -57,20 +39,20 @@ mod b64impl {
 // ============================================================
 
 mod curve25519impl {
-    use super::{ArgError, B64};
+    use super::B64;
+    use crate::{Error, Pos, Result};
     use std::convert::TryInto;
     use tor_llcrypto::pk::curve25519::PublicKey;
 
     pub struct Curve25519Public(PublicKey);
 
     impl std::str::FromStr for Curve25519Public {
-        type Err = ArgError;
-        fn from_str(s: &str) -> Result<Self, ArgError> {
+        type Err = Error;
+        fn from_str(s: &str) -> Result<Self> {
             let b64: B64 = s.parse()?;
-            let arry: [u8; 32] = b64
-                .as_bytes()
-                .try_into()
-                .map_err(|_| ArgError::Generic("wrong length"))?;
+            let arry: [u8; 32] = b64.as_bytes().try_into().map_err(|_| {
+                Error::BadArgument(0, Pos::at(s), "bad length for curve25519 key.".into())
+            })?;
             Ok(Curve25519Public(arry.into()))
         }
     }
@@ -85,17 +67,17 @@ mod curve25519impl {
 // ============================================================
 
 mod timeimpl {
-    use super::ArgError;
+    use crate::{Error, Pos, Result};
     use std::time::SystemTime;
 
     pub struct ISO8601TimeSp(SystemTime);
 
     impl std::str::FromStr for ISO8601TimeSp {
-        type Err = ArgError;
-        fn from_str(s: &str) -> Result<ISO8601TimeSp, ArgError> {
+        type Err = Error;
+        fn from_str(s: &str) -> Result<ISO8601TimeSp> {
             use chrono::{DateTime, NaiveDateTime, Utc};
-            let d =
-                NaiveDateTime::parse_from_str(s, "%Y-%m-%d %H:%M:%S").map_err(ArgError::BadTime)?;
+            let d = NaiveDateTime::parse_from_str(s, "%Y-%m-%d %H:%M:%S")
+                .map_err(|e| Error::BadArgument(0, Pos::at(s), format!("invalid time: {}", e)))?;
             let dt = DateTime::<Utc>::from_utc(d, Utc);
             Ok(ISO8601TimeSp(dt.into()))
         }
diff --git a/tor-netdoc/src/routerdesc.rs b/tor-netdoc/src/routerdesc.rs
index b2a4844c2..7788d15c3 100644
--- a/tor-netdoc/src/routerdesc.rs
+++ b/tor-netdoc/src/routerdesc.rs
@@ -396,14 +396,11 @@ impl RouterDesc {
         let uptime = body.maybe(UPTIME).parse_arg(0)?;
 
         // published time.
-        let published = {
-            let p_item = body.get_required(PUBLISHED)?;
-            let p: ISO8601TimeSp = p_item
-                .args_as_str()
-                .parse()
-                .map_err(|e: ArgError| Error::BadArgument(1, p_item.pos(), e.to_string()))?;
-            p.into()
-        };
+        let published = body
+            .get_required(PUBLISHED)?
+            .args_as_str()
+            .parse::<ISO8601TimeSp>()?
+            .into();
 
         // ntor key
         // XXXX technically this isn't "required"