rust/src/test/ui-fulldeps/proc-macro/auxiliary/parent-source-spans.rs

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// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// no-prefer-dynamic
#![feature(proc_macro)]
#![crate_type = "proc-macro"]
extern crate proc_macro;
proc_macro: Reorganize public API This commit is a reorganization of the `proc_macro` crate's public user-facing API. This is the result of a number of discussions at the recent Rust All-Hands where we're hoping to get the `proc_macro` crate into ship shape for stabilization of a subset of its functionality in the Rust 2018 release. The reorganization here is motivated by experiences from the `proc-macro2`, `quote`, and `syn` crates on crates.io (and other crates which depend on them). The main focus is future flexibility along with making a few more operations consistent and/or fixing bugs. A summary of the changes made from today's `proc_macro` API is: * The `TokenNode` enum has been removed and the public fields of `TokenTree` have also been removed. Instead the `TokenTree` type is now a public enum (what `TokenNode` was) and each variant is an opaque struct which internally contains `Span` information. This makes the various tokens a bit more consistent, require fewer wrappers, and otherwise provides good future-compatibility as opaque structs are easy to modify later on. * `Literal` integer constructors have been expanded to be unambiguous as to what they're doing and also allow for more future flexibility. Previously constructors like `Literal::float` and `Literal::integer` were used to create unsuffixed literals and the concrete methods like `Literal::i32` would create a suffixed token. This wasn't immediately clear to all users (the suffixed/unsuffixed aspect) and having *one* constructor for unsuffixed literals required us to pick a largest type which may not always be true. To fix these issues all constructors are now of the form `Literal::i32_unsuffixed` or `Literal::i32_suffixed` (for all integral types). This should allow future compatibility as well as being immediately clear what's suffixed and what isn't. * Each variant of `TokenTree` internally contains a `Span` which can also be configured via `set_span`. For example `Literal` and `Term` now both internally contain a `Span` rather than having it stored in an auxiliary location. * Constructors of all tokens are called `new` now (aka `Term::intern` is gone) and most do not take spans. Manufactured tokens typically don't have a fresh span to go with them and the span is purely used for error-reporting **except** the span for `Term`, which currently affects hygiene. The default spans for all these constructed tokens is `Span::call_site()` for now. The `Term` type's constructor explicitly requires passing in a `Span` to provide future-proofing against possible hygiene changes. It's intended that a first pass of stabilization will likely only stabilize `Span::call_site()` which is an explicit opt-in for "I would like no hygiene here please". The intention here is to make this explicit in procedural macros to be forwards-compatible with a hygiene-specifying solution. * Some of the conversions for `TokenStream` have been simplified a little. * The `TokenTreeIter` iterator was renamed to `token_stream::IntoIter`. Overall the hope is that this is the "final pass" at the API of `TokenStream` and most of `TokenTree` before stabilization. Explicitly left out here is any changes to `Span`'s API which will likely need to be re-evaluated before stabilization. All changes in this PR have already been reflected to the [`proc-macro2`], `quote`, and `syn` crates. New versions of all these crates have also been published to crates.io. Once this lands in nightly I plan on making an internals post again summarizing the changes made here and also calling on all macro authors to give the APIs a spin and see how they work. Hopefully pending no major issues we can then have an FCP to stabilize later this cycle! [`proc-macro2`]: https://docs.rs/proc-macro2/0.3.1/proc_macro2/
2018-04-02 10:19:32 -05:00
use proc_macro::{TokenStream, TokenTree, Span};
fn lit_span(tt: TokenTree) -> (Span, String) {
proc_macro: Reorganize public API This commit is a reorganization of the `proc_macro` crate's public user-facing API. This is the result of a number of discussions at the recent Rust All-Hands where we're hoping to get the `proc_macro` crate into ship shape for stabilization of a subset of its functionality in the Rust 2018 release. The reorganization here is motivated by experiences from the `proc-macro2`, `quote`, and `syn` crates on crates.io (and other crates which depend on them). The main focus is future flexibility along with making a few more operations consistent and/or fixing bugs. A summary of the changes made from today's `proc_macro` API is: * The `TokenNode` enum has been removed and the public fields of `TokenTree` have also been removed. Instead the `TokenTree` type is now a public enum (what `TokenNode` was) and each variant is an opaque struct which internally contains `Span` information. This makes the various tokens a bit more consistent, require fewer wrappers, and otherwise provides good future-compatibility as opaque structs are easy to modify later on. * `Literal` integer constructors have been expanded to be unambiguous as to what they're doing and also allow for more future flexibility. Previously constructors like `Literal::float` and `Literal::integer` were used to create unsuffixed literals and the concrete methods like `Literal::i32` would create a suffixed token. This wasn't immediately clear to all users (the suffixed/unsuffixed aspect) and having *one* constructor for unsuffixed literals required us to pick a largest type which may not always be true. To fix these issues all constructors are now of the form `Literal::i32_unsuffixed` or `Literal::i32_suffixed` (for all integral types). This should allow future compatibility as well as being immediately clear what's suffixed and what isn't. * Each variant of `TokenTree` internally contains a `Span` which can also be configured via `set_span`. For example `Literal` and `Term` now both internally contain a `Span` rather than having it stored in an auxiliary location. * Constructors of all tokens are called `new` now (aka `Term::intern` is gone) and most do not take spans. Manufactured tokens typically don't have a fresh span to go with them and the span is purely used for error-reporting **except** the span for `Term`, which currently affects hygiene. The default spans for all these constructed tokens is `Span::call_site()` for now. The `Term` type's constructor explicitly requires passing in a `Span` to provide future-proofing against possible hygiene changes. It's intended that a first pass of stabilization will likely only stabilize `Span::call_site()` which is an explicit opt-in for "I would like no hygiene here please". The intention here is to make this explicit in procedural macros to be forwards-compatible with a hygiene-specifying solution. * Some of the conversions for `TokenStream` have been simplified a little. * The `TokenTreeIter` iterator was renamed to `token_stream::IntoIter`. Overall the hope is that this is the "final pass" at the API of `TokenStream` and most of `TokenTree` before stabilization. Explicitly left out here is any changes to `Span`'s API which will likely need to be re-evaluated before stabilization. All changes in this PR have already been reflected to the [`proc-macro2`], `quote`, and `syn` crates. New versions of all these crates have also been published to crates.io. Once this lands in nightly I plan on making an internals post again summarizing the changes made here and also calling on all macro authors to give the APIs a spin and see how they work. Hopefully pending no major issues we can then have an FCP to stabilize later this cycle! [`proc-macro2`]: https://docs.rs/proc-macro2/0.3.1/proc_macro2/
2018-04-02 10:19:32 -05:00
match tt {
TokenTree::Literal(..) |
TokenTree::Group(..) => (tt.span(), tt.to_string().trim().into()),
_ => panic!("expected a literal in token tree, got: {:?}", tt)
}
}
#[proc_macro]
pub fn parent_source_spans(input: TokenStream) -> TokenStream {
let mut tokens = input.into_iter();
let (sp1, str1) = lit_span(tokens.next().expect("first string"));
let _ = tokens.next();
let (sp2, str2) = lit_span(tokens.next().expect("second string"));
sp1.error(format!("first final: {}", str1)).emit();
sp2.error(format!("second final: {}", str2)).emit();
if let (Some(p1), Some(p2)) = (sp1.parent(), sp2.parent()) {
p1.error(format!("first parent: {}", str1)).emit();
p2.error(format!("second parent: {}", str2)).emit();
if let (Some(gp1), Some(gp2)) = (p1.parent(), p2.parent()) {
gp1.error(format!("first grandparent: {}", str1)).emit();
gp2.error(format!("second grandparent: {}", str2)).emit();
}
}
sp1.source().error(format!("first source: {}", str1)).emit();
sp2.source().error(format!("second source: {}", str2)).emit();
"ok".parse().unwrap()
}