Merge pull request #516 from dtolnay/probe

Make all use of nightly go through probed interface

Author: dtolnay

build.rs

@@ -21,6 +21,7 @@ fn main() {
         println!("cargo:rustc-check-cfg=cfg(no_source_text)");
         println!("cargo:rustc-check-cfg=cfg(proc_macro_span)");
         println!("cargo:rustc-check-cfg=cfg(procmacro2_backtrace)");
+        println!("cargo:rustc-check-cfg=cfg(procmacro2_build_probe)");
         println!("cargo:rustc-check-cfg=cfg(procmacro2_nightly_testing)");
         println!("cargo:rustc-check-cfg=cfg(procmacro2_semver_exempt)");
         println!("cargo:rustc-check-cfg=cfg(randomize_layout)");
@@ -67,7 +68,7 @@ fn main() {
         return;
     }
 
-    println!("cargo:rerun-if-changed=build/probe.rs");
+    println!("cargo:rerun-if-changed=src/probe/proc_macro_span.rs");
 
     let proc_macro_span;
     let consider_rustc_bootstrap;
@@ -148,7 +149,7 @@ fn compile_probe(rustc_bootstrap: bool) -> bool {
     let rustc = cargo_env_var("RUSTC");
     let out_dir = cargo_env_var("OUT_DIR");
     let out_subdir = Path::new(&out_dir).join("probe");
-    let probefile = Path::new("build").join("probe.rs");
+    let probefile = Path::new("src").join("probe").join("proc_macro_span.rs");
 
     if let Err(err) = fs::create_dir(&out_subdir) {
         if err.kind() != ErrorKind::AlreadyExists {
@@ -172,6 +173,7 @@ fn compile_probe(rustc_bootstrap: bool) -> bool {
     }
 
     cmd.stderr(Stdio::null())
+        .arg("--cfg=procmacro2_build_probe")
         .arg("--edition=2021")
         .arg("--crate-name=proc_macro2")
         .arg("--crate-type=lib")

src/lib.rs

@@ -141,6 +141,7 @@ extern crate proc_macro;
 
 mod marker;
 mod parse;
+mod probe;
 mod rcvec;
 
 #[cfg(wrap_proc_macro)]

src/probe.rs

@@ -0,0 +1,4 @@
+#![allow(dead_code)]
+
+#[cfg(proc_macro_span)]
+pub(crate) mod proc_macro_span;

build/probe.rs renamed to src/probe/proc_macro_span.rs

@@ -2,7 +2,7 @@
 // If the current toolchain is able to compile it, then proc-macro2 is able to
 // offer these APIs too.
 
-#![feature(proc_macro_span)]
+#![cfg_attr(procmacro2_build_probe, feature(proc_macro_span))]
 
 extern crate proc_macro;
 
@@ -38,4 +38,5 @@ pub fn subspan<R: RangeBounds<usize>>(this: &Literal, range: R) -> Option<Span>
 }
 
 // Include in sccache cache key.
+#[cfg(procmacro2_build_probe)]
 const _: Option<&str> = option_env!("RUSTC_BOOTSTRAP");

src/wrapper.rs

@@ -2,6 +2,8 @@ use crate::detection::inside_proc_macro;
 use crate::fallback::{self, FromStr2 as _};
 #[cfg(span_locations)]
 use crate::location::LineColumn;
+#[cfg(proc_macro_span)]
+use crate::probe::proc_macro_span;
 use crate::{Delimiter, Punct, Spacing, TokenTree};
 use core::fmt::{self, Debug, Display};
 #[cfg(span_locations)]
@@ -421,7 +423,7 @@ impl Span {
     pub(crate) fn byte_range(&self) -> Range<usize> {
         match self {
             #[cfg(proc_macro_span)]
-            Span::Compiler(s) => s.byte_range(),
+            Span::Compiler(s) => proc_macro_span::byte_range(s),
             #[cfg(not(proc_macro_span))]
             Span::Compiler(_) => 0..0,
             Span::Fallback(s) => s.byte_range(),
@@ -433,8 +435,8 @@ impl Span {
         match self {
             #[cfg(proc_macro_span)]
             Span::Compiler(s) => LineColumn {
-                line: s.line(),
-                column: s.column().saturating_sub(1),
+                line: proc_macro_span::line(s),
+                column: proc_macro_span::column(s).saturating_sub(1),
             },
             #[cfg(not(proc_macro_span))]
             Span::Compiler(_) => LineColumn { line: 0, column: 0 },
@@ -447,10 +449,10 @@ impl Span {
         match self {
             #[cfg(proc_macro_span)]
             Span::Compiler(s) => {
-                let end = s.end();
+                let end = proc_macro_span::end(s);
                 LineColumn {
-                    line: end.line(),
-                    column: end.column().saturating_sub(1),
+                    line: proc_macro_span::line(&end),
+                    column: proc_macro_span::column(&end).saturating_sub(1),
                 }
             }
             #[cfg(not(proc_macro_span))]
@@ -478,7 +480,7 @@ impl Span {
     pub(crate) fn join(&self, other: Span) -> Option<Span> {
         let ret = match (self, other) {
             #[cfg(proc_macro_span)]
-            (Span::Compiler(a), Span::Compiler(b)) => Span::Compiler(a.join(b)?),
+            (Span::Compiler(a), Span::Compiler(b)) => Span::Compiler(proc_macro_span::join(a, b)?),
             (Span::Fallback(a), Span::Fallback(b)) => Span::Fallback(a.join(b)?),
             _ => return None,
         };
@@ -921,7 +923,7 @@ impl Literal {
     pub(crate) fn subspan<R: RangeBounds<usize>>(&self, range: R) -> Option<Span> {
         match self {
             #[cfg(proc_macro_span)]
-            Literal::Compiler(lit) => lit.subspan(range).map(Span::Compiler),
+            Literal::Compiler(lit) => proc_macro_span::subspan(lit, range).map(Span::Compiler),
             #[cfg(not(proc_macro_span))]
             Literal::Compiler(_lit) => None,
             Literal::Fallback(lit) => lit.subspan(range).map(Span::Fallback),