Replace completely std::error with failure crate

Author: t-botz

src/bin/main.rs

@@ -11,6 +11,7 @@
 #![cfg(not(test))]
 
 extern crate env_logger;
+extern crate failure;
 extern crate getopts;
 extern crate rustfmt_nightly as rustfmt;
 
@@ -19,6 +20,8 @@ use std::fs::File;
 use std::io::{self, stdout, Read, Write};
 use std::path::PathBuf;
 
+use failure::err_msg;
+
 use getopts::{Matches, Options};
 
 use rustfmt::{emit_post_matter, emit_pre_matter, load_config, CliOptions, Config, FmtResult,
@@ -167,7 +170,7 @@ fn execute(opts: &Options) -> FmtResult<(WriteMode, Summary)> {
             Ok((WriteMode::None, Summary::default()))
         }
         Operation::ConfigOutputDefault { path } => {
-            let toml = Config::default().all_options().to_toml()?;
+            let toml = Config::default().all_options().to_toml().map_err(err_msg)?;
             if let Some(path) = path {
                 let mut file = File::create(path)?;
                 file.write_all(toml.as_bytes())?;
@@ -186,7 +189,9 @@ fn execute(opts: &Options) -> FmtResult<(WriteMode, Summary)> {
 
             // parse file_lines
             if let Some(ref file_lines) = matches.opt_str("file-lines") {
-                config.set().file_lines(file_lines.parse()?);
+                config
+                    .set()
+                    .file_lines(file_lines.parse().map_err(err_msg)?);
                 for f in config.file_lines().files() {
                     match *f {
                         FileName::Custom(ref f) if f == "stdin" => {}
@@ -273,7 +278,7 @@ fn format(
     // that were used during formatting as TOML.
     if let Some(path) = minimal_config_path {
         let mut file = File::create(path)?;
-        let toml = config.used_options().to_toml()?;
+        let toml = config.used_options().to_toml().map_err(err_msg)?;
         file.write_all(toml.as_bytes())?;
     }
 

src/config/config_type.rs

@@ -305,12 +305,12 @@ macro_rules! create_config {
             ///
             /// Return a `Config` if the config could be read and parsed from
             /// the file, Error otherwise.
-            pub(super) fn from_toml_path(file_path: &Path) -> Result<Config, Error> {
+            pub(super) fn from_toml_path(file_path: &Path) -> Result<Config, ::failure::Error> {
                 let mut file = File::open(&file_path)?;
                 let mut toml = String::new();
                 file.read_to_string(&mut toml)?;
                 Config::from_toml(&toml, file_path.parent().unwrap())
-                    .map_err(|err| Error::new(ErrorKind::InvalidData, err))
+                    .map_err(::failure::err_msg)
             }
 
             /// Resolve the config for input in `dir`.
@@ -322,12 +322,12 @@ macro_rules! create_config {
             ///
             /// Returns the `Config` to use, and the path of the project file if there was
             /// one.
-            pub(super) fn from_resolved_toml_path(dir: &Path) -> Result<(Config, Option<PathBuf>), Error> {
+            pub(super) fn from_resolved_toml_path(dir: &Path) -> Result<(Config, Option<PathBuf>), ::failure::Error> {
 
                 /// Try to find a project file in the given directory and its parents.
                 /// Returns the path of a the nearest project file if one exists,
                 /// or `None` if no project file was found.
-                fn resolve_project_file(dir: &Path) -> Result<Option<PathBuf>, Error> {
+                fn resolve_project_file(dir: &Path) -> Result<Option<PathBuf>, ::failure::Error> {
                     let mut current = if dir.is_relative() {
                         env::current_dir()?.join(dir)
                     } else {

src/config/mod.rs

@@ -12,16 +12,17 @@ use regex::Regex;
 use std::cell::Cell;
 use std::default::Default;
 use std::fs::File;
-use std::io::{Error, ErrorKind, Read};
+use std::io::{ErrorKind, Read};
 use std::path::{Path, PathBuf};
 use std::{env, fs};
 
-use {FmtError, FmtResult};
+use FmtResult;
 
 use config::config_type::ConfigType;
 use config::file_lines::FileLines;
 pub use config::lists::*;
 pub use config::options::*;
+use failure::Error;
 
 #[macro_use]
 pub mod config_type;
@@ -161,11 +162,9 @@ pub fn load_config(
     };
 
     let result = if let Some(over_ride) = over_ride {
-        Config::from_toml_path(over_ride.as_ref())
-            .map(|p| (p, Some(over_ride.to_owned())))
-            .map_err(FmtError::from)
+        Config::from_toml_path(over_ride.as_ref()).map(|p| (p, Some(over_ride.to_owned())))
     } else if let Some(file_path) = file_path {
-        Config::from_resolved_toml_path(file_path).map_err(FmtError::from)
+        Config::from_resolved_toml_path(file_path)
     } else {
         Ok((Config::default(), None))
     };
@@ -181,7 +180,7 @@ pub fn load_config(
 // Check for the presence of known config file names (`rustfmt.toml, `.rustfmt.toml`) in `dir`
 //
 // Return the path if a config file exists, empty if no file exists, and Error for IO errors
-fn get_toml_path(dir: &Path) -> Result<Option<PathBuf>, Error> {
+fn get_toml_path(dir: &Path) -> FmtResult<Option<PathBuf>> {
     const CONFIG_FILE_NAMES: [&str; 2] = [".rustfmt.toml", "rustfmt.toml"];
     for config_file_name in &CONFIG_FILE_NAMES {
         let config_file = dir.join(config_file_name);
@@ -193,7 +192,7 @@ fn get_toml_path(dir: &Path) -> Result<Option<PathBuf>, Error> {
             // find the project file yet, and continue searching.
             Err(e) => {
                 if e.kind() != ErrorKind::NotFound {
-                    return Err(e);
+                    return Err(Error::from(e));
                 }
             }
             _ => {}
@@ -204,10 +203,10 @@ fn get_toml_path(dir: &Path) -> Result<Option<PathBuf>, Error> {
 
 fn config_path(options: &CliOptions) -> FmtResult<Option<PathBuf>> {
     let config_path_not_found = |path: &str| -> FmtResult<Option<PathBuf>> {
-        Err(FmtError::from(format!(
+        Err(format_err!(
             "Error: unable to find a config file for the given path: `{}`",
             path
-        )))
+        ))
     };
 
     // Read the config_path and convert to parent dir if a file is provided.

src/config/options.rs

@@ -14,7 +14,9 @@ use config::config_type::ConfigType;
 use config::file_lines::FileLines;
 use config::lists::*;
 use config::Config;
-use {FmtError, FmtResult, WRITE_MODE_LIST};
+use {FmtResult, WRITE_MODE_LIST};
+
+use failure::err_msg;
 
 use getopts::Matches;
 use std::collections::HashSet;
@@ -332,8 +334,8 @@ impl CliOptions {
             .map(|c| c == "nightly")
             .unwrap_or(false);
         if unstable_features && !rust_nightly {
-            return Err(FmtError::from(
-                "Unstable features are only available on Nightly channel",
+            return Err(format_err!(
+                "Unstable features are only available on Nightly channel"
             ));
         } else {
             options.unstable_features = unstable_features;
@@ -345,22 +347,23 @@ impl CliOptions {
             if let Ok(write_mode) = WriteMode::from_str(write_mode) {
                 options.write_mode = Some(write_mode);
             } else {
-                return Err(FmtError::from(format!(
+                return Err(format_err!(
                     "Invalid write-mode: {}, expected one of {}",
-                    write_mode, WRITE_MODE_LIST
-                )));
+                    write_mode,
+                    WRITE_MODE_LIST
+                ));
             }
         }
 
         if let Some(ref color) = matches.opt_str("color") {
             match Color::from_str(color) {
                 Ok(color) => options.color = Some(color),
-                _ => return Err(FmtError::from(format!("Invalid color: {}", color))),
+                _ => return Err(format_err!("Invalid color: {}", color)),
             }
         }
 
         if let Some(ref file_lines) = matches.opt_str("file-lines") {
-            options.file_lines = file_lines.parse()?;
+            options.file_lines = file_lines.parse().map_err(err_msg)?;
         }
 
         if matches.opt_present("skip-children") {

src/lib.rs

@@ -19,6 +19,7 @@
 #[macro_use]
 extern crate derive_new;
 extern crate diff;
+#[macro_use]
 extern crate failure;
 extern crate getopts;
 extern crate itertools;
@@ -38,7 +39,6 @@ extern crate toml;
 extern crate unicode_segmentation;
 
 use std::collections::HashMap;
-use std::error;
 use std::fmt;
 use std::io::{self, stdout, Write};
 use std::panic::{catch_unwind, AssertUnwindSafe};
@@ -64,8 +64,7 @@ pub use config::options::CliOptions;
 pub use config::summary::Summary;
 pub use config::{file_lines, load_config, Config, WriteMode};
 
-pub type FmtError = Box<error::Error + Send + Sync>;
-pub type FmtResult<T> = std::result::Result<T, FmtError>;
+pub type FmtResult<T> = std::result::Result<T, failure::Error>;
 
 pub const WRITE_MODE_LIST: &str =
     "[replace|overwrite|display|plain|diff|coverage|checkstyle|check]";
@@ -896,7 +895,7 @@ pub enum Input {
 
 pub fn format_and_emit_report(input: Input, config: &Config) -> FmtResult<Summary> {
     if !config.version_meets_requirement() {
-        return Err(FmtError::from("Version mismatch"));
+        return Err(format_err!("Version mismatch"));
     }
     let out = &mut stdout();
     match format_input(input, config, Some(out)) {