Handle command spawn failures more gracefully

src/command.rs

@@ -1,3 +1,6 @@
+use anyhow::bail;
+use anyhow::Context;
+use anyhow::Result;
 use std::{
     io::Write,
     process::{Command, Stdio},
@@ -22,15 +25,21 @@ impl Default for CommandResult {
 }
 
 pub fn run(app: &mut App) {
+    app.command_result = match run_inner(app) {
+        Ok(c) => c,
+        Err(e) => CommandResult {
+            status_success: false,
+            stdout: vec![],
+            stderr: format!("{e:?}").as_bytes().to_vec(),
+        },
+    };
+}
+
+fn run_inner(app: &mut App) -> Result<CommandResult> {
     let args = match shellwords::split(&app.cmdline) {
         Ok(a) => a,
         Err(e) => {
-            app.command_result = CommandResult {
-                status_success: false,
-                stdout: vec![],
-                stderr: format!("Argument error: {e:?}").as_bytes().to_vec(),
-            };
-            return;
+            bail!("Argument error: {e:?}");
         }
     };
 
@@ -41,22 +50,20 @@ pub fn run(app: &mut App) {
         .stdout(Stdio::piped())
         .stderr(Stdio::piped())
         .spawn()
-        .expect("Could not spawn child process");
+        .context("Could not spawn child process")?;
 
-    let mut stdin = child.stdin.take().expect("Could not take stdin");
+    let mut stdin = child.stdin.take().context("Could not take stdin")?;
     let text_orig_clone = app.text_orig.clone();
     std::thread::spawn(move || {
-        stdin
-            .write_all(text_orig_clone.as_bytes())
-            .expect("Failed to write to stdin");
+        let _ = stdin.write_all(text_orig_clone.as_bytes());
     });
 
     // Collect the output
-    let output = child.wait_with_output().expect("Failed to read stdout");
+    let output = child.wait_with_output().context("Failed to read stdout")?;
 
-    app.command_result = CommandResult {
+    Ok(CommandResult {
         status_success: output.status.success(),
         stdout: output.stdout,
         stderr: output.stderr,
-    }
+    })
 }

src/main.rs

@@ -107,8 +107,8 @@ impl App {
                 hidden_options: vec![],
             },
             Template::Perl => Self {
-                cmdline: String::from("-p -e 's/./_/'"),
-                cmdline_position: 3_u16,
+                cmdline: String::from("-p -e 's///'"),
+                cmdline_position: 10_u16,
                 text_orig,
                 command_result: CommandResult::default(),
                 autorun: true,
@@ -292,8 +292,15 @@ fn ui<B: Backend>(f: &mut Frame<B>, app: &App) {
         chunks[0],
     );
     f.render_widget(
-        Paragraph::new(app.cmdline.as_ref())
-            .block(Block::default().title("Cmdline").borders(Borders::ALL)),
+        Paragraph::new(app.cmdline.as_ref()).block(
+            Block::default()
+                .title(format!(
+                    "Cmdline ({} {})",
+                    app.command,
+                    app.hidden_options.join(" ")
+                ))
+                .borders(Borders::ALL),
+        ),
         vertical_chunks[1],
     );