fix: panic on process.kill() after run (#7405)

This commit fixes panic caused by "unimplemented!()"
calls for some variants of "nix::errno::Errno".

Catch-all variant now returns "Error" class name
instead of panicking.

Co-authored-by: Bert Belder <bertbelder@gmail.com>

cli/errors.rs

@@ -156,12 +156,14 @@ fn get_url_parse_error_class(_error: &url::ParseError) -> &'static str {
 fn get_nix_error_class(error: &nix::Error) -> &'static str {
   use nix::errno::Errno::*;
   match error {
-    nix::Error::Sys(EPERM) => "PermissionDenied",
+    nix::Error::Sys(ECHILD) => "NotFound",
     nix::Error::Sys(EINVAL) => "TypeError",
     nix::Error::Sys(ENOENT) => "NotFound",
     nix::Error::Sys(ENOTTY) => "BadResource",
-    nix::Error::Sys(UnknownErrno) => unreachable!(),
-    nix::Error::Sys(_) => unreachable!(),
+    nix::Error::Sys(EPERM) => "PermissionDenied",
+    nix::Error::Sys(ESRCH) => "NotFound",
+    nix::Error::Sys(UnknownErrno) => "Error",
+    nix::Error::Sys(_) => "Error",
     nix::Error::InvalidPath => "TypeError",
     nix::Error::InvalidUtf8 => "InvalidData",
     nix::Error::UnsupportedOperation => unreachable!(),

cli/tests/unit/process_test.ts

@@ -375,6 +375,30 @@ unitTest({ perms: { run: true } }, async function runClose(): Promise<void> {
   p.stderr.close();
 });
 
+unitTest(
+  { perms: { run: true } },
+  async function runKillAfterStatus(): Promise<void> {
+    const p = Deno.run({
+      cmd: ["python", "-c", 'print("hello")'],
+    });
+    await p.status();
+
+    // On Windows the underlying Rust API returns `ERROR_ACCESS_DENIED`,
+    // which serves kind of as a catch all error code. More specific
+    // error codes do exist, e.g. `ERROR_WAIT_NO_CHILDREN`; it's unclear
+    // why they're not returned.
+    const expectedErrorType = Deno.build.os === "windows"
+      ? Deno.errors.PermissionDenied
+      : Deno.errors.NotFound;
+    assertThrows(
+      () => p.kill(Deno.Signal.SIGTERM),
+      expectedErrorType,
+    );
+
+    p.close();
+  },
+);
+
 unitTest(function signalNumbers(): void {
   if (Deno.build.os === "darwin") {
     assertEquals(Deno.Signal.SIGSTOP, 17);