Only initialize signal handler once (#2953)

Author: casey

src/run.rs

@@ -34,3 +34,17 @@ pub fn run(args: impl Iterator<Item = impl Into<OsString> + Clone>) -> Result<()
       error.code().unwrap_or(EXIT_FAILURE)
     })
 }
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn run_can_be_called_more_than_once() {
+    let tmp = testing::tempdir();
+    fs::write(tmp.path().join("justfile"), "foo:").unwrap();
+    let search_directory = format!("{}/", tmp.path().to_str().unwrap());
+    run(["just", &search_directory].iter()).unwrap();
+    run(["just", &search_directory].iter()).unwrap();
+  }
+}

src/signal_handler.rs

@@ -3,14 +3,19 @@ use super::*;
 pub(crate) struct SignalHandler {
   caught: Option<Signal>,
   children: BTreeMap<i32, Command>,
+  initialized: bool,
   verbosity: Verbosity,
 }
 
 impl SignalHandler {
   pub(crate) fn install(verbosity: Verbosity) -> RunResult<'static> {
     let mut instance = Self::instance();
     instance.verbosity = verbosity;
-    Platform::install_signal_handler(|signal| Self::instance().interrupt(signal))
+    if !instance.initialized {
+      Platform::install_signal_handler(|signal| Self::instance().handle(signal))?;
+      instance.initialized = true;
+    }
+    Ok(())
   }
 
   pub(crate) fn instance() -> MutexGuard<'static, Self> {
@@ -35,11 +40,12 @@ impl SignalHandler {
     Self {
       caught: None,
       children: BTreeMap::new(),
+      initialized: false,
       verbosity: Verbosity::default(),
     }
   }
 
-  fn interrupt(&mut self, signal: Signal) {
+  fn handle(&mut self, signal: Signal) {
     if signal.is_fatal() {
       if self.children.is_empty() {
         process::exit(signal.code());