Proper error handling within walk.rs

src/error.rs

@@ -1,10 +1,3 @@
-macro_rules! print_error {
-    ($($arg:tt)*) => (eprintln!("[fd error]: {}", format!($($arg)*)))
-}
-
-macro_rules! print_error_and_exit {
-    ($($arg:tt)*) => {
-        print_error!($($arg)*);
-        ::std::process::exit(1);
-    };
+pub fn print_error(msg: impl Into<String>) {
+    eprintln!("[fd error]: {}", msg.into());
 }

src/exec/command.rs

@@ -3,6 +3,7 @@ use std::io::Write;
 use std::process::Command;
 use std::sync::Mutex;
 
+use crate::error::print_error;
 use crate::exit_codes::ExitCode;
 
 /// Executes a command.
@@ -30,11 +31,11 @@ pub fn execute_command(mut cmd: Command, out_perm: &Mutex<()>) -> ExitCode {
             }
         }
         Err(ref why) if why.kind() == io::ErrorKind::NotFound => {
-            print_error!("Command not found: {:?}", cmd);
+            print_error(format!("Command not found: {:?}", cmd));
             ExitCode::GeneralError
         }
         Err(why) => {
-            print_error!("Problem while executing command: {}", why);
+            print_error(format!("Problem while executing command: {}", why));
             ExitCode::GeneralError
         }
     }

src/exec/job.rs

@@ -1,10 +1,13 @@
-use super::CommandTemplate;
-use crate::exit_codes::{merge_exitcodes, ExitCode};
-use crate::walk::WorkerResult;
 use std::path::PathBuf;
 use std::sync::mpsc::Receiver;
 use std::sync::{Arc, Mutex};
 
+use crate::error::print_error;
+use crate::exit_codes::{merge_exitcodes, ExitCode};
+use crate::walk::WorkerResult;
+
+use super::CommandTemplate;
+
 /// An event loop that listens for inputs from the `rx` receiver. Each received input will
 /// generate a command with the supplied command template. The generated command will then
 /// be executed, and this process will continue until the receiver's sender has closed.
@@ -25,7 +28,7 @@ pub fn job(
             Ok(WorkerResult::Entry(val)) => val,
             Ok(WorkerResult::Error(err)) => {
                 if show_filesystem_errors {
-                    print_error!("{}", err);
+                    print_error(err.to_string());
                 }
                 continue;
             }
@@ -50,7 +53,7 @@ pub fn batch(
         WorkerResult::Entry(val) => Some(val),
         WorkerResult::Error(err) => {
             if show_filesystem_errors {
-                print_error!("{}", err);
+                print_error(err.to_string());
             }
             None
         }

src/main.rs

@@ -303,9 +303,7 @@ fn run() -> Result<ExitCode> {
             )
         })?;
 
-    let exit_code = walk::scan(&dir_vec, Arc::new(re), Arc::new(config));
-
-    Ok(exit_code)
+    walk::scan(&dir_vec, Arc::new(re), Arc::new(config))
 }
 
 fn main() {

src/walk.rs

@@ -1,9 +1,3 @@
-use crate::exec;
-use crate::exit_codes::{merge_exitcodes, ExitCode};
-use crate::filesystem;
-use crate::options::Options;
-use crate::output;
-
 use std::borrow::Cow;
 use std::ffi::OsStr;
 use std::fs::{FileType, Metadata};
@@ -16,10 +10,18 @@ use std::sync::{Arc, Mutex};
 use std::thread;
 use std::time;
 
+use anyhow::{anyhow, Result};
 use ignore::overrides::OverrideBuilder;
 use ignore::{self, WalkBuilder};
 use regex::bytes::Regex;
 
+use crate::error::print_error;
+use crate::exec;
+use crate::exit_codes::{merge_exitcodes, ExitCode};
+use crate::filesystem;
+use crate::options::Options;
+use crate::output;
+
 /// The receiver thread can either be buffering results or directly streaming to the console.
 enum ReceiverMode {
     /// Receiver is still buffering in order to sort the results, if the search finishes fast
@@ -44,7 +46,7 @@ pub const MAX_BUFFER_LENGTH: usize = 1000;
 /// If the `--exec` argument was supplied, this will create a thread pool for executing
 /// jobs in parallel from a given command line and the discovered paths. Otherwise, each
 /// path will simply be written to standard output.
-pub fn scan(path_vec: &[PathBuf], pattern: Arc<Regex>, config: Arc<Options>) -> ExitCode {
+pub fn scan(path_vec: &[PathBuf], pattern: Arc<Regex>, config: Arc<Options>) -> Result<ExitCode> {
     let mut path_iter = path_vec.iter();
     let first_path_buf = path_iter
         .next()
@@ -54,14 +56,13 @@ pub fn scan(path_vec: &[PathBuf], pattern: Arc<Regex>, config: Arc<Options>) ->
     let mut override_builder = OverrideBuilder::new(first_path_buf.as_path());
 
     for pattern in &config.exclude_patterns {
-        let res = override_builder.add(pattern);
-        if res.is_err() {
-            print_error_and_exit!("Malformed exclude pattern '{}'", pattern);
-        }
+        override_builder
+            .add(pattern)
+            .map_err(|e| anyhow!("Malformed exclude pattern: {}", e))?;
     }
-    let overrides = override_builder.build().unwrap_or_else(|_| {
-        print_error_and_exit!("Mismatch in exclude patterns");
-    });
+    let overrides = override_builder
+        .build()
+        .map_err(|_| anyhow!("Mismatch in exclude patterns"))?;
 
     let mut walker = WalkBuilder::new(first_path_buf.as_path());
     walker
@@ -86,13 +87,10 @@ pub fn scan(path_vec: &[PathBuf], pattern: Arc<Regex>, config: Arc<Options>) ->
         match result {
             Some(ignore::Error::Partial(_)) => (),
             Some(err) => {
-                print_error!(
-                    "{}",
-                    format!(
-                        "Malformed pattern in custom ignore file. {}.",
-                        err.to_string()
-                    )
-                );
+                print_error(format!(
+                    "Malformed pattern in custom ignore file. {}.",
+                    err.to_string()
+                ));
             }
             None => (),
         }
@@ -131,7 +129,7 @@ pub fn scan(path_vec: &[PathBuf], pattern: Arc<Regex>, config: Arc<Options>) ->
         process::exit(ExitCode::KilledBySigint.into());
     }
 
-    exit_code
+    Ok(exit_code)
 }
 
 fn spawn_receiver(
@@ -231,7 +229,7 @@ fn spawn_receiver(
                     }
                     WorkerResult::Error(err) => {
                         if show_filesystem_errors {
-                            print_error!("{}", err);
+                            print_error(err.to_string());
                         }
                     }
                 }
@@ -344,12 +342,9 @@ fn spawn_senders(
             let entry_path = entry.path();
 
             let search_str: Cow<OsStr> = if config.search_full_path {
-                match filesystem::path_absolute_form(entry_path) {
-                    Ok(path_abs_buf) => Cow::Owned(path_abs_buf.as_os_str().to_os_string()),
-                    Err(_) => {
-                        print_error_and_exit!("Unable to retrieve absolute path.");
-                    }
-                }
+                let path_abs_buf = filesystem::path_absolute_form(entry_path)
+                    .expect("Retrieving absolute path succeeds");
+                Cow::Owned(path_abs_buf.as_os_str().to_os_string())
             } else {
                 match entry_path.file_name() {
                     Some(filename) => Cow::Borrowed(filename),