convert tolstoy/ to failure

Author: Grisha Kruglov

src/entity_builder.rs

@@ -381,9 +381,7 @@ mod testing {
     extern crate mentat_db;
 
     // For matching inside a test.
-    use mentat_db::ErrorKind::{
-        UnrecognizedEntid,
-    };
+    use mentat_db::DbError;
 
     use ::{
         Conn,
@@ -424,7 +422,7 @@ mod testing {
         let mut in_progress = conn.begin_transaction(&mut sqlite).expect("begun successfully");
 
         // This should fail: unrecognized entid.
-        if let Err(Error(MentatError::DbError(UnrecognizedEntid(e)), _)) = in_progress.transact_terms(terms, tempids) {
+        if let Ok(DbError::UnrecognizedEntid(e)) = in_progress.transact_terms(terms, tempids).expect_err("expected transact to fail").downcast() {
             assert_eq!(e, 999);
         } else {
             panic!("Should have rejected the entid.");

tolstoy/Cargo.toml

@@ -5,6 +5,8 @@ workspace = ".."
 authors = ["Grisha Kruglov <gkruglov@mozilla.com>"]
 
 [dependencies]
+failure = "0.1.1"
+failure_derive = "0.1.1"
 futures = "0.1"
 hyper = "0.11"
 tokio-core = "0.1"
@@ -15,8 +17,6 @@ serde_derive = "1.0"
 lazy_static = "0.2"
 uuid = { version = "0.5", features = ["v4", "serde"] }
 
-error-chain = { git = "https://github.com/rnewman/error-chain", branch = "rnewman/sync" }
-
 [dependencies.mentat_core]
 path = "../core"
 

tolstoy/src/errors.rs

@@ -10,63 +10,34 @@
 
 #![allow(dead_code)]
 
-use std;
-use hyper;
-use rusqlite;
-use uuid;
-use mentat_db;
-use serde_cbor;
-use serde_json;
+use failure::Error;
 
-error_chain! {
-    types {
-        Error, ErrorKind, ResultExt, Result;
-    }
-
-    foreign_links {
-        IOError(std::io::Error);
-        HttpError(hyper::Error);
-        HyperUriError(hyper::error::UriError);
-        SqlError(rusqlite::Error);
-        UuidParseError(uuid::ParseError);
-        Utf8Error(std::str::Utf8Error);
-        JsonError(serde_json::Error);
-        CborError(serde_cbor::error::Error);
-    }
+#[macro_export]
+macro_rules! bail {
+    ($e:expr) => (
+        return Err($e.into());
+    )
+}
 
-    links {
-        DbError(mentat_db::Error, mentat_db::ErrorKind);
-    }
+pub type Result<T> = ::std::result::Result<T, Error>;
 
-    errors {
-        TxIncorrectlyMapped(n: usize) {
-            description("encountered more than one uuid mapping for tx")
-            display("expected one, found {} uuid mappings for tx", n)
-        }
+#[derive(Debug, Fail)]
+pub enum TolstoyError {
+    #[fail(display = "Received bad response from the server: {}", _0)]
+    BadServerResponse(String),
 
-        UnexpectedState(t: String) {
-            description("encountered unexpected state")
-            display("encountered unexpected state: {}", t)
-        }
+    #[fail(display = "encountered more than one metadata value for key: {}", _0)]
+    DuplicateMetadata(String),
 
-        NotYetImplemented(t: String) {
-            description("not yet implemented")
-            display("not yet implemented: {}", t)
-        }
+    #[fail(display = "transaction processor didn't say it was done")]
+    TxProcessorUnfinished,
 
-        DuplicateMetadata(k: String) {
-            description("encountered more than one metadata value for key")
-            display("encountered more than one metadata value for key: {}", k)
-        }
+    #[fail(display = "expected one, found {} uuid mappings for tx", _0)]
+    TxIncorrectlyMapped(usize),
 
-        TxProcessorUnfinished {
-            description("Tx processor couldn't finish")
-            display("Tx processor couldn't finish")
-        }
+    #[fail(display = "encountered unexpected state: {}", _0)]
+    UnexpectedState(String),
 
-        BadServerResponse(s: String) {
-            description("Received bad response from the server")
-            display("Received bad response from the server: {}", s)
-        }
-    }
+    #[fail(display = "not yet implemented: {}", _0)]
+    NotYetImplemented(String),
 }

tolstoy/src/lib.rs

@@ -8,11 +8,9 @@
 // CONDITIONS OF ANY KIND, either express or implied. See the License for the
 // specific language governing permissions and limitations under the License.
 
-// For error_chain:
-#![recursion_limit="128"]
-
+extern crate failure;
 #[macro_use]
-extern crate error_chain;
+extern crate failure_derive;
 
 #[macro_use]
 extern crate lazy_static;
@@ -33,16 +31,15 @@ extern crate mentat_core;
 extern crate rusqlite;
 extern crate uuid;
 
+#[macro_use]
+pub mod errors;
 pub mod schema;
 pub mod metadata;
 pub mod tx_processor;
-pub mod errors;
 pub mod syncer;
 pub mod tx_mapper;
 pub use syncer::Syncer;
 pub use errors::{
-    Error,
-    ErrorKind,
+    TolstoyError,
     Result,
-    ResultExt,
 };

tolstoy/src/metadata.rs

@@ -15,7 +15,7 @@ use uuid::Uuid;
 
 use schema;
 use errors::{
-    ErrorKind,
+    TolstoyError,
     Result,
 };
 
@@ -42,7 +42,7 @@ impl HeadTrackable for SyncMetadataClient {
         let updated = tx.execute("UPDATE tolstoy_metadata SET value = ? WHERE key = ?",
             &[&uuid_bytes, &schema::REMOTE_HEAD_KEY])?;
         if updated != 1 {
-            bail!(ErrorKind::DuplicateMetadata(schema::REMOTE_HEAD_KEY.into()));
+            bail!(TolstoyError::DuplicateMetadata(schema::REMOTE_HEAD_KEY.into()));
         }
         Ok(())
     }

tolstoy/src/syncer.rs

@@ -31,7 +31,7 @@ use metadata::HeadTrackable;
 use schema::ensure_current_version;
 
 use errors::{
-    ErrorKind,
+    TolstoyError,
     Result,
 };
 
@@ -179,7 +179,7 @@ impl Syncer {
         let mut uploader = UploadingTxReceiver::new(remote_client, remote_head);
         Processor::process(db_tx, from_tx, &mut uploader)?;
         if !uploader.is_done {
-            bail!(ErrorKind::TxProcessorUnfinished);
+            bail!(TolstoyError::TxProcessorUnfinished);
         }
         // Last tx uuid uploaded by the tx receiver.
         // It's going to be our new head.
@@ -222,7 +222,7 @@ impl Syncer {
         // without walking the table at all, and use the tx index.
         Processor::process(&db_tx, None, &mut inquiring_tx_receiver)?;
         if !inquiring_tx_receiver.is_done {
-            bail!(ErrorKind::TxProcessorUnfinished);
+            bail!(TolstoyError::TxProcessorUnfinished);
         }
         let have_local_changes = match inquiring_tx_receiver.last_tx {
             Some(tx) => {
@@ -257,15 +257,15 @@ impl Syncer {
                 Syncer::upload_ours(&mut db_tx, Some(upload_from_tx), &remote_client, &remote_head)?;
             } else {
                 d(&format!("Unable to fast-forward the server; missing local tx mapping"));
-                bail!(ErrorKind::TxIncorrectlyMapped(0));
+                bail!(TolstoyError::TxIncorrectlyMapped(0));
             }
 
         // We diverged from the server.
         // We'll need to rebase/merge ourselves on top of it.
         } else {
             d(&format!("server changed since last sync."));
 
-            bail!(ErrorKind::NotYetImplemented(
+            bail!(TolstoyError::NotYetImplemented(
                 format!("Can't yet sync against changed server. Local head {:?}, remote head {:?}", locally_known_remote_head, remote_head)
             ));
         }

tolstoy/src/tx_mapper.rs

@@ -14,7 +14,7 @@ use uuid::Uuid;
 use mentat_core::Entid;
 
 use errors::{
-    ErrorKind,
+    TolstoyError,
     Result,
 };
 
@@ -59,7 +59,7 @@ impl TxMapper {
         if txs.len() == 0 {
             return Ok(None);
         } else if txs.len() > 1 {
-            bail!(ErrorKind::TxIncorrectlyMapped(txs.len()));
+            bail!(TolstoyError::TxIncorrectlyMapped(txs.len()));
         }
         Ok(Some(txs.remove(0)?))
     }
@@ -79,7 +79,7 @@ impl TxMapper {
         if uuids.len() == 0 {
             return Ok(None);
         } else if uuids.len() > 1 {
-            bail!(ErrorKind::TxIncorrectlyMapped(uuids.len()));
+            bail!(TolstoyError::TxIncorrectlyMapped(uuids.len()));
         }
         Ok(Some(uuids.remove(0)?))
     }