feat: add `--log-file` flag to keep track of some debug info, which includes panics.

Previously, when `dua i` was used, panics would be hard to observe, if at all,
as they would print to the alternate screen. Now, when the `--log-file dua.log`
is specified, the panic will be emitted into the log file instead and thus won't
be lost anymore.

This may help with debugging in future.

2 files changed, 4 insertions, 5 deletions

diff --git a/src/main.rs b/src/main.rs
index 42bb4f3..818d971 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,9 +1,8 @@
 #![forbid(unsafe_code, rust_2018_idioms, unsafe_code)]
 use anyhow::Result;
-#[macro_use]
-extern crate log;
 use clap::Parser;
 use dua::TraversalSorting;
+use log::info;
 use simplelog::{Config, LevelFilter, WriteLogger};
 use std::fs::OpenOptions;
 use std::{fs, io, io::Write, path::PathBuf, process};
@@ -27,6 +26,7 @@ fn main() -> Result<()> {
     let opt: options::Args = options::Args::parse_from(wild::args_os());
 
     if let Some(log_file) = &opt.log_file {
+        log_panics::init();
         WriteLogger::init(
             LevelFilter::Info,
             Config::default(),
@@ -36,9 +36,8 @@ fn main() -> Result<()> {
                 .append(true)
                 .open(log_file)?,
         )?;
+        info!("dua options={opt:#?}");
     }
-    info!("dua-cli has started");
-    info!("opt={:#?}", opt);
 
     let walk_options = dua::WalkOptions {
         threads: opt.threads,
diff --git a/src/options.rs b/src/options.rs
index 60e0875..a59a90b 100644
--- a/src/options.rs
+++ b/src/options.rs
@@ -80,7 +80,7 @@ pub struct Args {
     #[clap(value_parser)]
     pub input: Vec<PathBuf>,
 
-    /// If set, dua will log debug information to a file.
+    /// Write a log file with debug information, including panics.
     #[clap(long)]
     pub log_file: Option<PathBuf>,
 }