From 866b9e16a866a51644d10760ea2fdd062f0c902f Mon Sep 17 00:00:00 2001
From: sharkdp <davidpeter@web.de>
Date: Thu, 11 Oct 2018 22:50:37 +0200
Subject: [PATCH] Add error handling

---
 src/app.rs    | 15 ++++++++-------
 src/config.rs | 38 ++++++++++++++++++++++++--------------
 src/main.rs   |  2 +-
 3 files changed, 33 insertions(+), 22 deletions(-)

diff --git a/src/app.rs b/src/app.rs
index 0d32bab7..d5dd2b8f 100644
--- a/src/app.rs
+++ b/src/app.rs
@@ -81,19 +81,19 @@ pub struct App {
 }
 
 impl App {
-    pub fn new() -> Self {
+    pub fn new() -> Result<Self> {
         #[cfg(windows)]
         let _ = ansi_term::enable_ansi_support();
 
         let interactive_output = atty::is(Stream::Stdout);
 
-        App {
-            matches: Self::matches(interactive_output),
+        Ok(App {
+            matches: Self::matches(interactive_output)?,
             interactive_output,
-        }
+        })
     }
 
-    fn matches(interactive_output: bool) -> ArgMatches<'static> {
+    fn matches(interactive_output: bool) -> Result<ArgMatches<'static>> {
         let args = if wild::args_os().nth(1) == Some("cache".into())
             || wild::args_os().any(|arg| arg == OsStr::new("--no-config"))
         {
@@ -104,7 +104,8 @@ impl App {
             let mut cli_args = wild::args_os();
 
             // Read arguments from bats config file
-            let mut args = get_args_from_config_file();
+            let mut args =
+                get_args_from_config_file().chain_err(|| "Could not parse configuration file")?;
 
             // Put the zero-th CLI argument (program name) first
             args.insert(0, cli_args.next().unwrap());
@@ -115,7 +116,7 @@ impl App {
             args
         };
 
-        clap_app::build_app(interactive_output).get_matches_from(args)
+        Ok(clap_app::build_app(interactive_output).get_matches_from(args))
     }
 
     pub fn config(&self) -> Result<Config> {
diff --git a/src/config.rs b/src/config.rs
index 9cf3eb70..b5833f5c 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -1,44 +1,54 @@
+use std::env;
 use std::ffi::OsString;
 use std::fs;
 
 use shell_words;
 
 use dirs::PROJECT_DIRS;
+use util::transpose;
 
-pub fn get_args_from_config_file() -> Vec<OsString> {
+pub fn get_args_from_config_file() -> Result<Vec<OsString>, shell_words::ParseError> {
     let config_file = PROJECT_DIRS.config_dir().join("config");
-    fs::read_to_string(config_file)
-        .map(|content| get_args_from_str(&content))
-        .unwrap_or(vec![])
+    Ok(transpose(
+        fs::read_to_string(config_file)
+            .ok()
+            .map(|content| get_args_from_str(&content)),
+    )?
+    .unwrap_or(vec![]))
 }
 
-fn get_args_from_str<'a>(content: &'a str) -> Vec<OsString> {
-    content
+fn get_args_from_str<'a>(content: &'a str) -> Result<Vec<OsString>, shell_words::ParseError> {
+    let args_per_line = content
         .split('\n')
         .map(|line| line.trim())
         .filter(|line| !line.is_empty())
         .filter(|line| !line.starts_with("#"))
-        .flat_map(|line| shell_words::split(line).unwrap())
+        .map(|line| shell_words::split(line))
+        .collect::<Result<Vec<_>, _>>()?;
+
+    Ok(args_per_line
+        .iter()
+        .flatten()
         .map(|line| line.into())
-        .collect()
+        .collect())
 }
 
 #[test]
 fn empty() {
-    let args = get_args_from_str("");
+    let args = get_args_from_str("").unwrap();
     assert!(args.is_empty());
 }
 
 #[test]
 fn single() {
-    assert_eq!(vec!["--plain"], get_args_from_str("--plain"));
+    assert_eq!(vec!["--plain"], get_args_from_str("--plain").unwrap());
 }
 
 #[test]
 fn multiple() {
     assert_eq!(
         vec!["--plain", "--language=cpp"],
-        get_args_from_str("--plain --language=cpp")
+        get_args_from_str("--plain --language=cpp").unwrap()
     );
 }
 
@@ -46,7 +56,7 @@ fn multiple() {
 fn quotes() {
     assert_eq!(
         vec!["--theme", "Sublime Snazzy"],
-        get_args_from_str("--theme \"Sublime Snazzy\"")
+        get_args_from_str("--theme \"Sublime Snazzy\"").unwrap()
     );
 }
 
@@ -60,7 +70,7 @@ fn multi_line() {
     ";
     assert_eq!(
         vec!["-p", "--style", "numbers,changes", "--color=always"],
-        get_args_from_str(config)
+        get_args_from_str(config).unwrap()
     );
 }
 
@@ -78,6 +88,6 @@ fn comments() {
     ";
     assert_eq!(
         vec!["-p", "--style", "numbers,changes", "--color=always"],
-        get_args_from_str(config)
+        get_args_from_str(config).unwrap()
     );
 }
diff --git a/src/main.rs b/src/main.rs
index a5484193..31f9503f 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -196,7 +196,7 @@ fn run_controller(config: &Config) -> Result<bool> {
 /// Returns `Err(..)` upon fatal errors. Otherwise, returns `Some(true)` on full success and
 /// `Some(false)` if any intermediate errors occurred (were printed).
 fn run() -> Result<bool> {
-    let app = App::new();
+    let app = App::new()?;
 
     match app.matches.subcommand() {
         ("cache", Some(cache_matches)) => {