Rollup merge of #111571 - jhpratt:proc-macro-span, r=m-ou-se

Implement proposed API for `proc_macro_span`

As proposed in [#54725 (comment)](#54725 (comment)). I have omitted the byte-level API as it's already available as [`Span::byte_range`](https://doc.rust-lang.org/nightly/proc_macro/struct.Span.html#method.byte_range).

`@rustbot` label +A-proc-macros

r? `@m-ou-se`

Cargo.lock

@@ -2580,9 +2580,9 @@ checksum = "dbf0c48bc1d91375ae5c3cd81e3722dff1abcf81a30960240640d223f59fe0e5"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.56"
+version = "1.0.60"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2b63bdb0cd06f1f4dedf69b254734f9b45af66e4a031e42a7480257d9898b435"
+checksum = "dec2b086b7a862cf4de201096214fa870344cf922b2b30c167badb3af3195406"
 dependencies = [
  "unicode-ident",
 ]

compiler/rustc_expand/src/proc_macro_server.rs

@@ -2,7 +2,7 @@ use crate::base::ExtCtxt;
 use pm::bridge::{
     server, DelimSpan, Diagnostic, ExpnGlobals, Group, Ident, LitKind, Literal, Punct, TokenTree,
 };
-use pm::{Delimiter, Level, LineColumn};
+use pm::{Delimiter, Level};
 use rustc_ast as ast;
 use rustc_ast::token;
 use rustc_ast::tokenstream::{self, Spacing::*, TokenStream};
@@ -648,23 +648,22 @@ impl server::Span for Rustc<'_, '_> {
 
         Range { start: relative_start_pos.0 as usize, end: relative_end_pos.0 as usize }
     }
-
-    fn start(&mut self, span: Self::Span) -> LineColumn {
-        let loc = self.sess().source_map().lookup_char_pos(span.lo());
-        LineColumn { line: loc.line, column: loc.col.to_usize() }
+    fn start(&mut self, span: Self::Span) -> Self::Span {
+        span.shrink_to_lo()
     }
 
-    fn end(&mut self, span: Self::Span) -> LineColumn {
-        let loc = self.sess().source_map().lookup_char_pos(span.hi());
-        LineColumn { line: loc.line, column: loc.col.to_usize() }
+    fn end(&mut self, span: Self::Span) -> Self::Span {
+        span.shrink_to_hi()
     }
 
-    fn before(&mut self, span: Self::Span) -> Self::Span {
-        span.shrink_to_lo()
+    fn line(&mut self, span: Self::Span) -> usize {
+        let loc = self.sess().source_map().lookup_char_pos(span.lo());
+        loc.line
     }
 
-    fn after(&mut self, span: Self::Span) -> Self::Span {
-        span.shrink_to_hi()
+    fn column(&mut self, span: Self::Span) -> usize {
+        let loc = self.sess().source_map().lookup_char_pos(span.lo());
+        loc.col.to_usize() + 1
     }
 
     fn join(&mut self, first: Self::Span, second: Self::Span) -> Option<Self::Span> {

library/proc_macro/src/bridge/mod.rs

@@ -8,7 +8,7 @@
 
 #![deny(unsafe_code)]
 
-use crate::{Delimiter, Level, LineColumn, Spacing};
+use crate::{Delimiter, Level, Spacing};
 use std::fmt;
 use std::hash::Hash;
 use std::marker;
@@ -95,10 +95,10 @@ macro_rules! with_api {
                 fn parent($self: $S::Span) -> Option<$S::Span>;
                 fn source($self: $S::Span) -> $S::Span;
                 fn byte_range($self: $S::Span) -> Range<usize>;
-                fn start($self: $S::Span) -> LineColumn;
-                fn end($self: $S::Span) -> LineColumn;
-                fn before($self: $S::Span) -> $S::Span;
-                fn after($self: $S::Span) -> $S::Span;
+                fn start($self: $S::Span) -> $S::Span;
+                fn end($self: $S::Span) -> $S::Span;
+                fn line($self: $S::Span) -> usize;
+                fn column($self: $S::Span) -> usize;
                 fn join($self: $S::Span, other: $S::Span) -> Option<$S::Span>;
                 fn subspan($self: $S::Span, start: Bound<usize>, end: Bound<usize>) -> Option<$S::Span>;
                 fn resolved_at($self: $S::Span, at: $S::Span) -> $S::Span;
@@ -299,7 +299,6 @@ mark_noop! {
     Delimiter,
     LitKind,
     Level,
-    LineColumn,
     Spacing,
 }
 
@@ -319,7 +318,6 @@ rpc_encode_decode!(
         Help,
     }
 );
-rpc_encode_decode!(struct LineColumn { line, column });
 rpc_encode_decode!(
     enum Spacing {
         Alone,

library/proc_macro/src/lib.rs

@@ -43,7 +43,6 @@ mod diagnostic;
 #[unstable(feature = "proc_macro_diagnostic", issue = "54140")]
 pub use diagnostic::{Diagnostic, Level, MultiSpan};
 
-use std::cmp::Ordering;
 use std::ops::{Range, RangeBounds};
 use std::path::PathBuf;
 use std::str::FromStr;
@@ -494,28 +493,32 @@ impl Span {
         self.0.byte_range()
     }
 
-    /// Gets the starting line/column in the source file for this span.
+    /// Creates an empty span pointing to directly before this span.
     #[unstable(feature = "proc_macro_span", issue = "54725")]
-    pub fn start(&self) -> LineColumn {
-        self.0.start().add_1_to_column()
+    pub fn start(&self) -> Span {
+        Span(self.0.start())
     }
 
-    /// Gets the ending line/column in the source file for this span.
+    /// Creates an empty span pointing to directly after this span.
     #[unstable(feature = "proc_macro_span", issue = "54725")]
-    pub fn end(&self) -> LineColumn {
-        self.0.end().add_1_to_column()
+    pub fn end(&self) -> Span {
+        Span(self.0.end())
     }
 
-    /// Creates an empty span pointing to directly before this span.
-    #[unstable(feature = "proc_macro_span_shrink", issue = "87552")]
-    pub fn before(&self) -> Span {
-        Span(self.0.before())
+    /// The one-indexed line of the source file where the span starts.
+    ///
+    /// To obtain the line of the span's end, use `span.end().line()`.
+    #[unstable(feature = "proc_macro_span", issue = "54725")]
+    pub fn line(&self) -> usize {
+        self.0.line()
     }
 
-    /// Creates an empty span pointing to directly after this span.
-    #[unstable(feature = "proc_macro_span_shrink", issue = "87552")]
-    pub fn after(&self) -> Span {
-        Span(self.0.after())
+    /// The one-indexed column of the source file where the span starts.
+    ///
+    /// To obtain the column of the span's end, use `span.end().column()`.
+    #[unstable(feature = "proc_macro_span", issue = "54725")]
+    pub fn column(&self) -> usize {
+        self.0.column()
     }
 
     /// Creates a new span encompassing `self` and `other`.
@@ -586,44 +589,6 @@ impl fmt::Debug for Span {
     }
 }
 
-/// A line-column pair representing the start or end of a `Span`.
-#[unstable(feature = "proc_macro_span", issue = "54725")]
-#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
-pub struct LineColumn {
-    /// The 1-indexed line in the source file on which the span starts or ends (inclusive).
-    #[unstable(feature = "proc_macro_span", issue = "54725")]
-    pub line: usize,
-    /// The 1-indexed column (number of bytes in UTF-8 encoding) in the source
-    /// file on which the span starts or ends (inclusive).
-    #[unstable(feature = "proc_macro_span", issue = "54725")]
-    pub column: usize,
-}
-
-impl LineColumn {
-    fn add_1_to_column(self) -> Self {
-        LineColumn { line: self.line, column: self.column + 1 }
-    }
-}
-
-#[unstable(feature = "proc_macro_span", issue = "54725")]
-impl !Send for LineColumn {}
-#[unstable(feature = "proc_macro_span", issue = "54725")]
-impl !Sync for LineColumn {}
-
-#[unstable(feature = "proc_macro_span", issue = "54725")]
-impl Ord for LineColumn {
-    fn cmp(&self, other: &Self) -> Ordering {
-        self.line.cmp(&other.line).then(self.column.cmp(&other.column))
-    }
-}
-
-#[unstable(feature = "proc_macro_span", issue = "54725")]
-impl PartialOrd for LineColumn {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        Some(self.cmp(other))
-    }
-}
-
 /// The source file of a given `Span`.
 #[unstable(feature = "proc_macro_span", issue = "54725")]
 #[derive(Clone)]

src/bootstrap/Cargo.lock

@@ -527,9 +527,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.56"
+version = "1.0.60"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2b63bdb0cd06f1f4dedf69b254734f9b45af66e4a031e42a7480257d9898b435"
+checksum = "dec2b086b7a862cf4de201096214fa870344cf922b2b30c167badb3af3195406"
 dependencies = [
  "unicode-ident",
 ]

src/tools/miri/Cargo.lock

@@ -529,9 +529,9 @@ checksum = "5b40af805b3121feab8a3c29f04d8ad262fa8e0561883e7653e024ae4479e6de"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.56"
+version = "1.0.60"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2b63bdb0cd06f1f4dedf69b254734f9b45af66e4a031e42a7480257d9898b435"
+checksum = "dec2b086b7a862cf4de201096214fa870344cf922b2b30c167badb3af3195406"
 dependencies = [
  "unicode-ident",
 ]

src/tools/miri/cargo-miri/Cargo.lock

@@ -179,9 +179,9 @@ checksum = "ece97ea872ece730aed82664c424eb4c8291e1ff2480247ccf7409044bc6479f"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.56"
+version = "1.0.60"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2b63bdb0cd06f1f4dedf69b254734f9b45af66e4a031e42a7480257d9898b435"
+checksum = "dec2b086b7a862cf4de201096214fa870344cf922b2b30c167badb3af3195406"
 dependencies = [
  "unicode-ident",
 ]

src/tools/miri/test-cargo-miri/Cargo.lock

@@ -83,9 +83,9 @@ version = "0.1.0"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.49"
+version = "1.0.60"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "57a8eca9f9c4ffde41714334dee777596264c7825420f521abc92b5b5deb63a5"
+checksum = "dec2b086b7a862cf4de201096214fa870344cf922b2b30c167badb3af3195406"
 dependencies = [
  "unicode-ident",
 ]

src/tools/miri/test_dependencies/Cargo.lock

@@ -193,9 +193,9 @@ checksum = "5b40af805b3121feab8a3c29f04d8ad262fa8e0561883e7653e024ae4479e6de"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.49"
+version = "1.0.60"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "57a8eca9f9c4ffde41714334dee777596264c7825420f521abc92b5b5deb63a5"
+checksum = "dec2b086b7a862cf4de201096214fa870344cf922b2b30c167badb3af3195406"
 dependencies = [
  "unicode-ident",
 ]

src/tools/rust-analyzer/Cargo.lock

@@ -1304,9 +1304,9 @@ version = "0.0.0"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.56"
+version = "1.0.60"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2b63bdb0cd06f1f4dedf69b254734f9b45af66e4a031e42a7480257d9898b435"
+checksum = "dec2b086b7a862cf4de201096214fa870344cf922b2b30c167badb3af3195406"
 dependencies = [
  "unicode-ident",
 ]

src/tools/rust-analyzer/crates/proc-macro-srv/src/server.rs

@@ -8,10 +8,7 @@
 //!
 //! FIXME: No span and source file information is implemented yet
 
-use proc_macro::{
-    bridge::{self, server},
-    LineColumn,
-};
+use proc_macro::bridge::{self, server};
 
 mod token_stream;
 pub use token_stream::TokenStream;
@@ -304,14 +301,6 @@ impl server::Span for RustAnalyzer {
         // FIXME handle span
         Range { start: 0, end: 0 }
     }
-    fn start(&mut self, _span: Self::Span) -> LineColumn {
-        // FIXME handle span
-        LineColumn { line: 0, column: 0 }
-    }
-    fn end(&mut self, _span: Self::Span) -> LineColumn {
-        // FIXME handle span
-        LineColumn { line: 0, column: 0 }
-    }
     fn join(&mut self, first: Self::Span, _second: Self::Span) -> Option<Self::Span> {
         // Just return the first span again, because some macros will unwrap the result.
         Some(first)
@@ -330,13 +319,23 @@ impl server::Span for RustAnalyzer {
         tt::TokenId::unspecified()
     }
 
-    fn after(&mut self, _self_: Self::Span) -> Self::Span {
+    fn end(&mut self, _self_: Self::Span) -> Self::Span {
         tt::TokenId::unspecified()
     }
 
-    fn before(&mut self, _self_: Self::Span) -> Self::Span {
+    fn start(&mut self, _self_: Self::Span) -> Self::Span {
         tt::TokenId::unspecified()
     }
+
+    fn line(&mut self, _span: Self::Span) -> usize {
+        // FIXME handle line
+        0
+    }
+
+    fn column(&mut self, _span: Self::Span) -> usize {
+        // FIXME handle column
+        0
+    }
 }
 
 impl server::Symbol for RustAnalyzer {

tests/ui/macros/auxiliary/proc_macro_sequence.rs

@@ -8,11 +8,6 @@ extern crate proc_macro;
 
 use proc_macro::{quote, Span, TokenStream, TokenTree};
 
-fn assert_same_span(a: Span, b: Span) {
-    assert_eq!(a.start(), b.start());
-    assert_eq!(a.end(), b.end());
-}
-
 // This macro generates a macro with the same macro definition as `manual_foo` in
 // `same-sequence-span.rs` but with the same span for all sequences.
 #[proc_macro]

tests/ui/macros/same-sequence-span.stderr

@@ -17,15 +17,14 @@ LL |                $(= $z:tt)*
 error: `$x:expr` may be followed by `$y:tt`, which is not allowed for `expr` fragments
   --> $DIR/same-sequence-span.rs:19:1
    |
+LL | | }
+   | |_________________________________^ not allowed after `expr` fragments
+LL |
 LL |   proc_macro_sequence::make_foo!();
    |   ^-------------------------------
    |   |
    |  _in this macro invocation
    | |
-LL | |
-LL | |
-LL | | fn main() {}
-   | |_________________________________^ not allowed after `expr` fragments
    |
    = note: allowed there are: `=>`, `,` or `;`
    = note: this error originates in the macro `proc_macro_sequence::make_foo` (in Nightly builds, run with -Z macro-backtrace for more info)

tests/ui/proc-macro/auxiliary/api/cmp.rs

@@ -1,18 +1,9 @@
-use proc_macro::{LineColumn, Punct, Spacing};
+use proc_macro::{Punct, Spacing};
 
 pub fn test() {
-    test_line_column_ord();
     test_punct_eq();
 }
 
-fn test_line_column_ord() {
-    let line0_column0 = LineColumn { line: 0, column: 0 };
-    let line0_column1 = LineColumn { line: 0, column: 1 };
-    let line1_column0 = LineColumn { line: 1, column: 0 };
-    assert!(line0_column0 < line0_column1);
-    assert!(line0_column1 < line1_column0);
-}
-
 fn test_punct_eq() {
     let colon_alone = Punct::new(':', Spacing::Alone);
     assert_eq!(colon_alone, ':');

tests/ui/proc-macro/auxiliary/assert-span-pos.rs

@@ -26,10 +26,9 @@ pub fn assert_span_pos(input: TokenStream) -> TokenStream {
     let line: usize = str1.parse().unwrap();
     let col: usize = str2.parse().unwrap();
 
-    let sp1s = sp1.start();
-    if (line, col) != (sp1s.line, sp1s.column) {
+    if (line, col) != (sp1.line(), sp1.column()) {
         let msg = format!("line/column mismatch: ({}, {}) != ({}, {})", line, col,
-            sp1s.line, sp1s.column);
+            sp1.line(), sp1.column());
         sp1.error(msg).emit();
     }
 

tests/ui/proc-macro/auxiliary/macro-only-syntax.rs

@@ -81,7 +81,7 @@ fn expect_brace(tokens: &mut token_stream::IntoIter) -> token_stream::IntoIter {
 
 fn check_useful_span(token: TokenTree, expected_filename: &str) {
     let span = token.span();
-    assert!(span.start().column < span.end().column);
+    assert!(span.column() < span.end().column());
 
     let source_path = span.source_file().path();
     let filename = source_path.components().last().unwrap();