Use 'anyhow' instead of 'failure' to simplify code and reduce bloat

Cargo.toml

@@ -10,8 +10,6 @@ license = "MIT"
 include = ["src/**/*", "Cargo.*", "LICENSE", "README.md", "CHANGELOG.md", "!**/*_test/*"]
 
 [dependencies]
-failure = "0.1.1"
-failure-tools = "4.0.2"
 argh = "0.1.3"
 jwalk = "0.5.0"
 byte-unit = "4"
@@ -27,6 +25,7 @@ num_cpus = "1.10.0"
 unicode-segmentation = "1.3.0"
 filesize = "0.2.0"
 flume = {version = "0.7.1", default-features = false}
+anyhow = "1.0.31"
 
 [[bin]]
 name="dua"

src/aggregate.rs

@@ -1,5 +1,5 @@
 use crate::{crossdev, InodeFilter, WalkOptions, WalkResult};
-use failure::Error;
+use anyhow::Result;
 use filesize::PathExt;
 use std::borrow::Cow;
 use std::{fmt, io, path::Path};
@@ -14,7 +14,7 @@ pub fn aggregate(
     compute_total: bool,
     sort_by_size_in_bytes: bool,
     paths: impl IntoIterator<Item = impl AsRef<Path>>,
-) -> Result<(WalkResult, Statistics), Error> {
+) -> Result<(WalkResult, Statistics)> {
     let mut res = WalkResult::default();
     let mut stats = Statistics::default();
     stats.smallest_file_in_bytes = u128::max_value();
@@ -125,7 +125,7 @@ fn write_path<C: fmt::Display>(
     num_bytes: u128,
     num_errors: u64,
     path_color: C,
-) -> Result<(), io::Error> {
+) -> std::result::Result<(), io::Error> {
     writeln!(
         out,
         "{byte_color}{:>byte_column_width$}{byte_color_reset} {path_color}{}{path_color_reset}{}",

src/interactive/app/eventloop.rs

@@ -4,11 +4,11 @@ use crate::interactive::{
     ByteVisualization, CursorDirection, CursorMode, DisplayOptions, EntryDataBundle, MarkEntryMode,
     SortMode,
 };
+use anyhow::Result;
 use dua::{
     traverse::{Traversal, TreeIndex},
     WalkOptions, WalkResult,
 };
-use failure::Error;
 use std::{collections::BTreeMap, io, path::PathBuf};
 use termion::{event::Key, input::TermRead};
 use tui::backend::Backend;
@@ -51,7 +51,7 @@ impl AppState {
         traversal: &Traversal,
         display: DisplayOptions,
         terminal: &mut Terminal<B>,
-    ) -> Result<(), Error>
+    ) -> Result<()>
     where
         B: Backend,
     {
@@ -69,8 +69,8 @@ impl AppState {
         traversal: &mut Traversal,
         display: &mut DisplayOptions,
         terminal: &mut Terminal<B>,
-        keys: impl Iterator<Item = Result<Key, io::Error>>,
-    ) -> Result<ProcessingResult, Error>
+        keys: impl Iterator<Item = std::result::Result<Key, io::Error>>,
+    ) -> Result<ProcessingResult>
     where
         B: Backend,
     {
@@ -159,7 +159,7 @@ pub fn draw_window<B>(
     window: &mut MainWindow,
     props: MainWindowProps,
     terminal: &mut Terminal<B>,
-) -> Result<(), Error>
+) -> Result<()>
 where
     B: Backend,
 {
@@ -183,8 +183,8 @@ impl TerminalApp {
     pub fn process_events<B>(
         &mut self,
         terminal: &mut Terminal<B>,
-        keys: impl Iterator<Item = Result<Key, io::Error>>,
-    ) -> Result<WalkResult, Error>
+        keys: impl Iterator<Item = std::result::Result<Key, io::Error>>,
+    ) -> Result<WalkResult>
     where
         B: Backend,
     {
@@ -204,7 +204,7 @@ impl TerminalApp {
         options: WalkOptions,
         input: Vec<PathBuf>,
         mode: Interaction,
-    ) -> Result<Option<KeyboardInputAndApp>, Error>
+    ) -> Result<Option<KeyboardInputAndApp>>
     where
         B: Backend,
     {

src/interactive/app/handlers.rs

@@ -1,9 +1,7 @@
-use crate::interactive::widgets::MainWindow;
 use crate::interactive::{
     app::FocussedPane::*,
     path_of, sorted_entries,
-    widgets::MarkMode,
-    widgets::{HelpPane, MarkPane},
+    widgets::{HelpPane, MainWindow, MarkMode, MarkPane},
     AppState, DisplayOptions, EntryDataBundle,
 };
 use dua::traverse::{Traversal, TreeIndex};

src/interactive/app_test/journeys_readonly.rs

@@ -1,18 +1,18 @@
-use crate::{
-    interactive::app_test::utils::{
+use crate::interactive::{
+    app_test::utils::{
         fixture_str, index_by_name, initialized_app_and_terminal_from_fixture, node_by_index,
         node_by_name,
     },
-    interactive::app_test::FIXTURE_PATH,
-    interactive::SortMode,
+    app_test::FIXTURE_PATH,
+    SortMode,
 };
-use failure::Error;
+use anyhow::Result;
 use pretty_assertions::assert_eq;
 use std::ffi::OsString;
 use termion::input::TermRead;
 
 #[test]
-fn simple_user_journey_read_only() -> Result<(), Error> {
+fn simple_user_journey_read_only() -> Result<()> {
     let long_root = "sample-02/dir";
     let short_root = "sample-01";
     let (mut terminal, mut app) =

src/interactive/app_test/journeys_with_writes.rs

@@ -1,13 +1,13 @@
 use crate::interactive::app_test::utils::{
     initialized_app_and_terminal_from_paths, WritableFixture,
 };
-use failure::Error;
+use anyhow::Result;
 use pretty_assertions::assert_eq;
 use termion::event::Key;
 use termion::input::TermRead;
 
 #[test]
-fn basic_user_journey_with_deletion() -> Result<(), Error> {
+fn basic_user_journey_with_deletion() -> Result<()> {
     let fixture = WritableFixture::from("sample-02");
     let (mut terminal, mut app) = initialized_app_and_terminal_from_paths(&[fixture.root.clone()])?;
 

src/interactive/app_test/unit.rs

@@ -1,11 +1,11 @@
 use crate::interactive::app_test::utils::{
     debug, initialized_app_and_terminal_from_fixture, sample_01_tree, sample_02_tree,
 };
-use failure::Error;
+use anyhow::Result;
 use pretty_assertions::assert_eq;
 
 #[test]
-fn it_can_handle_ending_traversal_reaching_top_but_skipping_levels() -> Result<(), Error> {
+fn it_can_handle_ending_traversal_reaching_top_but_skipping_levels() -> Result<()> {
     let (_, app) = initialized_app_and_terminal_from_fixture(&["sample-01"])?;
     let expected_tree = sample_01_tree();
 
@@ -18,7 +18,7 @@ fn it_can_handle_ending_traversal_reaching_top_but_skipping_levels() -> Result<(
 }
 
 #[test]
-fn it_can_handle_ending_traversal_without_reaching_the_top() -> Result<(), Error> {
+fn it_can_handle_ending_traversal_without_reaching_the_top() -> Result<()> {
     let (_, app) = initialized_app_and_terminal_from_fixture(&["sample-02"])?;
     let expected_tree = sample_02_tree();