Handle ENOENT

[cadencemarseille]

Translate ENOENT to IoErrorKind::FileNotFound.

[alexcrichton]

Can you add a test for this as well?

[cadencemarseille]

Hi @alexcrichton,

I added a test that I have been trying to get working, but it always fails for some reason, even when I comment out the two asserts. Do you know why the test is not working? I'm confused because if I change line 71 of rust-pcre's package script and mistype "rust-pcre", then the io_error condition is raised and the IoErrorKind is FileNotFound (using rustc with this patch).

Every time I run make check-stage1-std NO_REBUILD=1 NO_BENCH=1 VERBOSE=1 it eventually fails with:

failures:
    run::tests::test_process_output_io_error_file_not_found
test result: FAILED. 1316 passed; 1 failed; 92 ignored; 0 measured
task '' failed at 'Some tests failed', /Users/cadencemarseille/Projects/rust/src/libextra/test.rs:168

[alexcrichton]

I suppose that this depends on the test case that you're trying here. I would recommend having a simpler test case which doesn't involve spawning processes. Otherwise there's a very large amount of unknown (to me) code in play so it's tough for me to understand what's going on here.

[cadencemarseille]

I split out the test code into a standalone file and it fails with:

task '' failed at 'called `Option::unwrap()` on a `None` value', /Users/cadencemarseille/Projects/rust/src/libstd/option.rs:135

This looks like Issue #10754 std::run functions fail after io_error.

As far as a simpler test, would a test that checks whether uv_error_to_io_error(ENOENT) returns a FileNotFound-kind IoError work?

[alexcrichton]

Sorry I didn't mean for this to become a long saga of figuring out how to write a test, I just wanted something in the code to assert that ENOENT showed up. As you found out in the unix tests, one of them gives ENOENT and that's good enough for me.

There are many ways to trigger an ENOENT without spawning a process, so if that's blocking you have you tried doing things like listing a directory that doesn't exist or reading a file that doesn't exist?

[alexcrichton]

We really frequently get different errors on windows, so for now it's fine to just have a different assertion for windows than you have for unix, e.g. assert_eq!(err, if cfg!(windows) { OtherIoError } else { FileNotFound})