Handle failure of OpenProcess

Author: ecstatic-morse

src/native/windows.rs

@@ -8,6 +8,9 @@ use winapi::um::winnt::PROCESS_TERMINATE;
 pub(crate) fn kill_process(id: u32) -> Fallible<()> {
     unsafe {
         let handle = OpenProcess(PROCESS_TERMINATE, 0, id);
+        if handle.is_null() {
+            bail!("OpenProcess for process {} failed", id);
+        }
         if TerminateProcess(handle, 101) == 0 {
             bail!("TerminateProcess for process {} failed", id);
         }
@@ -45,3 +48,20 @@ pub(crate) fn make_executable<P: AsRef<Path>>(path: P) -> Fallible<()> {
         failure::bail!("Downloaded binaries should be executable by default");
     }
 }
+
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::process::Command;
+
+    #[test]
+    fn test_kill_process() {
+        // Try to kill a sleep command
+        let mut cmd = Command::new("timeout").args(&["2"]).spawn().unwrap();
+        kill_process(cmd.id()).unwrap();
+
+        // Ensure it returns the code passed to `TerminateProcess`
+        assert_eq!(cmd.wait().unwrap().code(), Some(101));
+    }
+}