libstd: replace all `try!` with `?` in documentation examples
See #38644.
For the record, I used the following Perl one-liner and then manually fixed a couple of things it got wrong:
$ perl -p -i -e 's#(///.*)try!\((.*)\)#$1$2?#' src/libstd/**/*.rs
Use fs::symlink_metadata in doc for is_symlink
fs::metadata() follows symlinks so is_symlink() will always return
false. Use symlink_metadata instead in the example in the
documentation.
See issue #39088.
Document that `Metadata` can be obtained from `symlink_metadata`
When retrieving the information about a syslink (specifically, when invoking `Metadata::is_symlink`) you generally want the `syslink_metadata`. It would be natural to point at both options to retrieve a `Metadata` value, as they are both appropriate (for different use cases).
* Command::envs() now takes anything that is IntoIterator<Item=(K, V)>
where both K and V are AsRef<OsStr>.
* Since we're not 100% sure that's the right signature, envs() is
now marked unstable. (You can use envs() with HashMap<str, str> but
not Vec<(str, str)>, for instance.)
* Update the test to match.
* By analogy, args() now takes any IntoIterator<Item=S>, S: AsRef<OsStr>.
This should be uncontroversial.
Make rustbuild force_alloc_system rather than relying on stage0
This 'fixes' jemalloc-less local rebuilds, where we tell cargo that we're actually stage1 (this only fixes the rustbuild path, since I wasn't enthusiastic to dive into the makefiles).
There should be one effect from this PR: `--enable-local-rebuild --disable-jemalloc` will successfully build a stage0 std (rather than erroring). Ideally I think it'd be nice to specify an allocator preference in Cargo.toml/cargo command line (used when an allocator must be picked i.e. dylibs, not rlibs), but since that's not possible we can make do with a force_alloc_system feature. Sadly this locks you into a single allocator in the build libstd, making any eventual implementation of #38575 not quite right in this edge case, but clearly not many people exercise the combination of these two flags.
This PR is also a substitute for #37975 I think. The crucial difference is that the feature name here is distinct from the jemalloc feature (reused in the previous PR) - we don't want someone to be forced into alloc_system just for disabling jemalloc!
Fixes#39054
r? @alexcrichton
travis: Get an emscripten builder online
This commit adds a new entry to the Travis matrix which will execute emscripten
test suites. Along the way it updates a few bits of the test suite to continue
passing on emscripten, such as:
* Ignoring i128/u128 tests as they're presumably just not working (didn't
investigate as to why)
* Disabling a few process tests (not working on emscripten)
* Ignore some num tests in libstd (#39119)
* Fix some warnings when compiling
This commit adds a new entry to the Travis matrix which will execute emscripten
test suites. Along the way it updates a few bits of the test suite to continue
passing on emscripten, such as:
* Ignoring i128/u128 tests as they're presumably just not working (didn't
investigate as to why)
* Disabling a few process tests (not working on emscripten)
* Ignore some num tests in libstd (#39119)
* Fix some warnings when compiling
Show a conventional way to use process::exit when destructors are considered important and also
mention that the same caveats wrt destructors apply to exec as well.
fs::metadata() follows symlinks so is_symlink() will always return
false. Use symlink_metadata instead in the example in the
documentation.
See issue #39088.
PartialEq and PartialOrd between IpAddr and Ipv[46]Addr.
PartialEq was rather useful, so, I figured that I'd implement it. I added PartialOrd for good measure.
Minor improvements to docs in std::env structures/functions.
* Call functions "functions" instead of "methods".
* Link structures to their constructor functions
* Add other misc. documentation links
`ToSocketAddrs` is implemented for a number of different types,
including `(IpAddr, u16)`, `&str`, and various others, for the
convenience of being able to run things like
`TcpListener::bind("10.11.12.13:1415")`. However, because this is a
generic parameter with a trait bound, if you have a `String` you cannot
pass it in, either directly as `TcpListener::bind(string)`, or the
`TcpListener::bind(&string)` as you might expect due to deref coercion;
you have to use `TcpListener::bind(&*string)`, which is noisy and hard
to discover (though #39029 suggests better error messages to make it
more discoverable).
Rather than making people stumble over this, just implement
`ToSocketAddrs` for `String`.
std/net/udp: Improve set_nonblocking test
While writing a separate change, I noticed the current test for `UdpSocket::set_nonblocking()` is fairly ineffective.
This fixes the test so that it validates that a correct error is returned on calls to `recv()` when no data is available.
std: Ignore close_read_wakes_up on Windows
It looks like in practice at least this test will not pass on Windows.
Empirically it is prone to blocking forever, presumably because a call to
`shutdown` doesn't actually wake up other threads on Windows.
We don't document this as a guarantee for `shutdown`, nor do we internally rely
on it. This test originated in a time long since passed when it was leveraged
for canceling I/O, but nowadays there's nothing fancy happening in the standard
library so it's not really a productive test anyway, hence just ignoring it on
Windows.
Closes#31657
