implicit `Option`-returning doctests
This distinguishes `Option` and `Result`-returning doctests with implicit `main` method, where the former tests must end with `Some(())`.
Open question: Does this need a feature gate?
r? @GuillaumeGomez
rustdoc: set the default edition when pre-parsing a doctest
Fixes https://github.com/rust-lang/rust/issues/59313 (possibly more? i think we've had issues with parsing edition-specific syntax in doctests at some point)
When handling a doctest, rustdoc needs to parse it beforehand, so that it can see whether it declares a `fn main` or `extern crate my_crate` explicitly. However, while doing this, rustdoc doesn't set the "default edition" used by the parser like the regular compilation runs do. This caused a problem when parsing a doctest with an `async move` block in it, since it was expecting the `move` keyword to start a closure, not a block.
This PR changes the `rustdoc::test::make_test` function to set the parser's default edition while looking for a main function and `extern crate` statement. However, to do this, `make_test` needs to know what edition to set. Since this is also used during the HTML rendering process (to make playground URLs), now the HTML renderer needs to know about the default edition. Upshot: rendering standalone markdown files can now accept a "default edition" for their doctests with the `--edition` flag! (I'm pretty sure i waffled around how to set that a long time ago when we first added the `--edition` flag... `>_>`)
I'm posting this before i stop for the night so that i can write this description while it's still in my head, but before this merges i want to make sure that (1) the `rustdoc-ui/failed-doctest-output` test still works (i expect it doesn't), and (2) i add a test with the sample from the linked issue.
Modify doctest's auto-`fn main()` to allow `Result`s
This lets the default `fn main()` ~~return `impl Termination`~~ unwrap Results, which allows the use of `?` in most tests without adding it manually. This fixes#56260
~~Blocked on `std::process::Termination` stabilization.~~
Using `Termination` would have been cleaner, but this should work OK.
Previously calculating glob map was *opt-in*, however it did record
node id -> ident use for every use directive. This aims to see if we
can unconditionally calculate the glob map and not regress performance.
rustdoc: force binary filename for compiled doctests
Fixes https://github.com/rust-lang/rust/issues/57317, needed for https://github.com/rust-lang/rust-by-example/issues/1137
Right now, when building a doctest, rustdoc provides the compiler an output directory (a temp dir) but lets the compiler name the executable. If the doctest needs to be executed, it then tries to run a binary named `rust_out` from that directory. For the most part, this works fine. However, if the doctest sets its own crate name, the compiler uses that name for the output binary instead. This causes rustdoc to try to execute a nonexistent binary, causing the test to fail.
This PR changes the paths rustdoc gives to the compiler when building doctests to force the output *filename* instead of just the *directory*.
This commit completely removes usage of the `panictry!` macro from
outside libsyntax. The macro causes parse errors to be fatal, so using
it in libsyntax_ext caused parse failures *within* a syntax extension to
be fatal, which is probably not intended.
Furthermore, this commit adds spans to diagnostics emitted by empty
extensions if they were missing, à la #56491.
rustdoc: look for comments when scraping attributes/crates from doctests
Fixes https://github.com/rust-lang/rust/issues/56727
When scraping out crate-level attributes and `extern crate` statements, we wouldn't look for comments, so any presence of comments would shunt it and everything after it into "everything else". This could cause parsing issues when looking for `fn main` and `extern crate my_crate` later on, which would in turn cause rustdoc to incorrectly wrap a test with `fn main` when it already had one declared.
I took the opportunity to clean up the logic a little bit, but it would still benefit from a libsyntax-based loop like the `fn main` detection.
rustdoc: refactor: centralize all command-line argument parsing
This is something i've wanted to do for a while, since we keep having to add new arguments to places like `rust_input` or `core::run_core` whenever we add a new CLI flag or the like. Those functions have inflated up to 11-19, and in some cases hiding away the locations where some CLI flags were being parsed, obscuring their use. Now, we have a central place where all command-line configuration occurs, including argument validation.
One note about the design: i grouped together all the arguments that `html::render::run` needed, so that i could pass them on from compilation in one lump instead of trying to thread through individual items or clone the entire blob ahead of time.
One other thing this adds is that rustdoc also now recognizes all the `-Z` options that rustc does, since we were manually grabbing a few previously. Now we parse a full `DebuggingOptions` struct and hand it directly to rustc when scraping docs.
