Do not include error source() in display() format.

According to doc/Errors.md, and in keeping with current best
practices, we should not include display an error's `source()` as
part of that error's display method.  Instead, we should let the
caller decide to call source() and display that error in turn.

Part of #323.

crates/arti-client/src/err.rs

@@ -109,11 +109,11 @@ pub_if_error_detail! {
 #[non_exhaustive]
 enum ErrorDetail {
     /// Error setting up the channel manager
-    #[error("Error setting up the channel manager {0}")]
+    #[error("Error setting up the channel manager")]
     ChanMgrSetup(#[source] tor_chanmgr::Error), // TODO should this be its own type?
 
     /// Error setting up the circuit manager
-    #[error("Error setting up the circuit manager {0}")]
+    #[error("Error setting up the circuit manager")]
     CircMgrSetup(#[source] tor_circmgr::Error), // TODO should this be its own type?
 
     /// Failed to obtain exit circuit
@@ -128,15 +128,15 @@ enum ErrorDetail {
     },
 
     /// Error while getting a circuit
-    #[error("Directory state error {0}")]
+    #[error("Directory state error")]
     DirMgr(#[from] tor_dirmgr::Error),
 
     /// A protocol error while launching a stream
-    #[error("Protocol error while launching a stream: {0}")]
+    #[error("Protocol error while launching a stream")]
     Proto(#[from] tor_proto::Error),
 
     /// An error while interfacing with the persistent data layer.
-    #[error("Error from state manager: {0}")]
+    #[error("Error from state manager")]
     Persist(#[from] tor_persist::Error),
 
     /// We asked an exit to do something, and waited too long for an answer..
@@ -148,7 +148,7 @@ enum ErrorDetail {
     OnionAddressNotSupported,
 
     /// Unusable target address.
-    #[error("Could not parse target address: {0}")]
+    #[error("Could not parse target address")]
     Address(#[from] crate::address::TorAddrError),
 
     /// Hostname not valid.
@@ -160,11 +160,11 @@ enum ErrorDetail {
     LocalAddress,
 
     /// Building configuration for the client failed.
-    #[error("Configuration failed: {0}")]
+    #[error("Configuration failed")]
     Configuration(#[from] tor_config::ConfigBuildError),
 
     /// Unable to change configuration.
-    #[error("Reconfiguration failed: {0}")]
+    #[error("Reconfiguration failed")]
     Reconfigure(#[from] tor_config::ReconfigureError),
 
     /// Unable to spawn task

crates/fs-mistrust/src/err.rs

@@ -99,7 +99,7 @@ pub enum Error {
 
     /// A field was missing when we tried to construct a
     /// [`Mistrust`](crate::Mistrust).
-    #[error("Missing field: {0}")]
+    #[error("Missing field when constructing Mistrust")]
     MissingField(#[from] derive_builder::UninitializedFieldError),
 
     /// A  group that we were configured to trust could not be found.

crates/tor-cell/src/err.rs

@@ -12,13 +12,13 @@ use tor_error::{ErrorKind, HasKind};
 pub enum Error {
     /// An error that occurred in the tor_bytes crate while decoding an
     /// object.
-    #[error("parsing error: {0}")]
+    #[error("parsing error")]
     BytesErr(#[from] tor_bytes::Error),
     /// There was a programming error somewhere in the code.
-    #[error("Internal programming error: {0}")]
+    #[error("Internal programming error")]
     Internal(tor_error::Bug),
     /// Protocol violation at the channel level
-    #[error("channel protocol violation: {0}")]
+    #[error("channel protocol violation")]
     ChanProto(String),
     /// Tried to make or use a stream to an invalid destination address.
     #[error("invalid stream target address")]

crates/tor-chanmgr/src/err.rs

@@ -14,7 +14,7 @@ use tor_proto::ClockSkew;
 #[non_exhaustive]
 pub enum Error {
     /// A ChanTarget was given for which no channel could be built.
-    #[error("Target was unusable: {0}")]
+    #[error("Bug: Target was unusable")]
     UnusableTarget(#[source] tor_error::Bug),
 
     /// We were waiting on a pending channel, but it didn't succeed.
@@ -68,7 +68,7 @@ pub enum Error {
         cause: Arc<SpawnError>,
     },
     /// An internal error of some kind that should never occur.
-    #[error("Internal error: {0}")]
+    #[error("Internal error")]
     Internal(#[from] tor_error::Bug),
 }
 

crates/tor-circmgr/src/err.rs

@@ -29,7 +29,7 @@ pub enum Error {
 
     /// We were waiting on a pending circuits, but it failed.
     #[error("Pending circuit failed.")]
-    PendingFailed(Box<Error>),
+    PendingFailed(#[source] Box<Error>),
 
     /// We were told that we could use a given circuit, but before we got a
     /// chance to try it, its usage changed so that we had no longer find
@@ -79,11 +79,11 @@ pub enum Error {
     NoExit(String),
 
     /// Problem creating or updating a guard manager.
-    #[error("Problem creating or updating guards list: {0}")]
+    #[error("Problem creating or updating guards list")]
     GuardMgr(#[source] tor_guardmgr::GuardMgrError),
 
     /// Problem selecting a guard relay.
-    #[error("Unable to select a guard relay: {0}")]
+    #[error("Unable to select a guard relay")]
     Guard(#[from] tor_guardmgr::PickGuardError),
 
     /// Unable to get or build a circuit, despite retrying.
@@ -128,12 +128,12 @@ pub enum Error {
     },
 
     /// Problem loading or storing persistent state.
-    #[error("Problem loading or storing state: {0}")]
+    #[error("Problem loading or storing state")]
     State(#[from] tor_persist::Error),
 
     /// An error caused by a programming issue . or a failure in another
     /// library that we can't work around.
-    #[error("Programming issue: {0}")]
+    #[error("Programming error")]
     Bug(#[from] Bug),
 }
 

crates/tor-dirclient/src/err.rs

@@ -14,7 +14,7 @@ use crate::SourceInfo;
 #[non_exhaustive]
 pub enum Error {
     /// Error while getting a circuit
-    #[error("Error while getting a circuit {0}")]
+    #[error("Error while getting a circuit")]
     CircMgr(#[from] tor_circmgr::Error),
 
     /// An error that has occurred after we have contacted a directory cache and made a circuit to it.
@@ -50,11 +50,11 @@ pub enum RequestError {
     Utf8Encoding(#[from] std::string::FromUtf8Error),
 
     /// Io error while reading on connection
-    #[error("IO error: {0}")]
+    #[error("IO error")]
     IoError(#[source] Arc<std::io::Error>),
 
     /// A protocol error while launching a stream
-    #[error("Protocol error while launching a stream: {0}")]
+    #[error("Protocol error while launching a stream")]
     Proto(#[from] tor_proto::Error),
 
     /// Error when parsing http

crates/tor-dirmgr/src/err.rs

@@ -25,7 +25,7 @@ pub enum Error {
     #[error("corrupt cache: {0}")]
     CacheCorruption(&'static str),
     /// rusqlite gave us an error.
-    #[error("sqlite error: {0}")]
+    #[error("sqlite error")]
     SqliteError(#[source] Arc<rusqlite::Error>),
     /// A schema version that says we can't read it.
     #[error("unrecognized data storage schema")]
@@ -48,7 +48,7 @@ pub enum Error {
     #[error("storage error: {0}")]
     StorageError(String),
     /// An error given by the consensus diff crate.
-    #[error("consdiff error: {0}")]
+    #[error("consdiff error")]
     ConsensusDiffError(#[from] tor_consdiff::Error),
     /// Invalid UTF8 in directory response.
     #[error("invalid utf-8 from directory server")]
@@ -85,13 +85,13 @@ pub enum Error {
     #[error("object expired or not yet valid.")]
     UntimelyObject(#[from] tor_checkable::TimeValidityError),
     /// An error given by dirclient
-    #[error("dirclient error: {0}")]
+    #[error("dirclient error")]
     DirClientError(#[from] tor_dirclient::Error),
     /// An error given by the checkable crate.
-    #[error("checkable error: {0}")]
+    #[error("checkable error")]
     SignatureError(#[source] Arc<signature::Error>),
     /// An IO error occurred while manipulating storage on disk.
-    #[error("IO error: {0}")]
+    #[error("IO error")]
     IOError(#[source] Arc<std::io::Error>),
     /// An attempt was made to bootstrap a `DirMgr` created in offline mode.
     #[error("cannot bootstrap offline DirMgr")]
@@ -121,7 +121,7 @@ pub enum Error {
     },
 
     /// A programming problem, either in our code or the code calling it.
-    #[error("programming problem: {0}")]
+    #[error("programming problem")]
     Bug(#[from] tor_error::Bug),
 }
 

crates/tor-proto/src/channel.rs

@@ -511,17 +511,18 @@ pub(crate) mod test {
     #[test]
     fn send_bad() {
         tor_rtcompat::test_with_all_runtimes!(|_rt| async move {
+            use std::error::Error;
             let chan = fake_channel(fake_channel_details());
 
             let cell = ChanCell::new(7.into(), msg::Created2::new(&b"hihi"[..]).into());
             let e = chan.check_cell(&cell);
             assert!(e.is_err());
-            assert!(format!("{}", e.unwrap_err())
+            assert!(format!("{}", e.unwrap_err().source().unwrap())
                 .contains("Can't send CREATED2 cell on client channel"));
             let cell = ChanCell::new(0.into(), msg::Certs::new_empty().into());
             let e = chan.check_cell(&cell);
             assert!(e.is_err());
-            assert!(format!("{}", e.unwrap_err())
+            assert!(format!("{}", e.unwrap_err().source().unwrap())
                 .contains("Can't send CERTS cell after handshake is done"));
 
             let cell = ChanCell::new(5.into(), msg::Create2::new(2, &b"abc"[..]).into());

crates/tor-proto/src/util/err.rs

@@ -14,17 +14,17 @@ use tor_error::{ErrorKind, HasKind};
 pub enum Error {
     /// An error that occurred in the tor_bytes crate while decoding an
     /// object.
-    #[error("parsing error: {0}")]
+    #[error("parsing error")]
     BytesErr(#[from] tor_bytes::Error),
     /// An error that occurred from the io system when using a
     /// channel.
-    #[error("io error on channel: {0}")]
+    #[error("io error on channel")]
     ChanIoErr(#[source] Arc<std::io::Error>),
     /// An error from the io system that occurred when trying to connect a channel.
-    #[error("io error in handshake: {0}")]
+    #[error("io error in handshake")]
     HandshakeIoErr(#[source] Arc<std::io::Error>),
     /// An error occurred in the cell-handling layer.
-    #[error("cell encoding error: {0}")]
+    #[error("cell encoding error")]
     CellErr(#[source] tor_cell::Error),
     /// We tried to produce too much output for some function.
     #[error("couldn't produce that much output")]
@@ -88,11 +88,11 @@ pub enum Error {
     #[error("channel mismatch: {0}")]
     ChanMismatch(String),
     /// There was a programming error somewhere in our code, or the calling code.
-    #[error("Programming error: {0}")]
+    #[error("Programming error")]
     Bug(#[from] tor_error::Bug),
     /// Remote DNS lookup failed.
-    #[error("remote resolve failed: {0}")]
-    ResolveError(ResolveError),
+    #[error("remote resolve failed")]
+    ResolveError(#[source] ResolveError),
 }
 
 /// Details about an error received while resolving a domain