Remove usage of rustc_lexer::unescape in rust-analyzer

Cargo.lock

@@ -1270,6 +1270,7 @@ dependencies = [
  "edition",
  "expect-test",
  "ra-ap-rustc_lexer",
+ "rustc-literal-escaper",
  "stdx",
  "tracing",
 ]
@@ -1743,6 +1744,12 @@ version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "583034fd73374156e66797ed8e5b0d5690409c9226b22d87cb7f19821c05d152"
 
+[[package]]
+name = "rustc-literal-escaper"
+version = "0.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cfdd0fcb1409d38cb2d940400497e2384a4a04b8685ee92a0a7a8986ccd72115"
+
 [[package]]
 name = "rustc-stable-hash"
 version = "0.1.1"
@@ -1982,6 +1989,7 @@ dependencies = [
  "rayon",
  "rowan",
  "rustc-hash 2.0.0",
+ "rustc-literal-escaper",
  "rustc_apfloat",
  "smol_str",
  "stdx",

crates/parser/Cargo.toml

@@ -14,6 +14,7 @@ rust-version.workspace = true
 [dependencies]
 drop_bomb = "0.1.5"
 ra-ap-rustc_lexer.workspace = true
+rustc-literal-escaper = "0.0.1"
 tracing = { workspace = true, optional = true }
 
 edition.workspace = true

crates/parser/src/lexed_str.rs

@@ -10,7 +10,7 @@
 
 use std::ops;
 
-use rustc_lexer::unescape::{EscapeError, Mode};
+use rustc_literal_escaper::{EscapeError, Mode, unescape_byte, unescape_char, unescape_mixed, unescape_unicode};
 
 use crate::{
     Edition,
@@ -282,7 +282,7 @@ impl<'a> Converter<'a> {
                     let text = &self.res.text[self.offset + 1..][..len - 1];
                     let i = text.rfind('\'').unwrap();
                     let text = &text[..i];
-                    if let Err(e) = rustc_lexer::unescape::unescape_char(text) {
+                    if let Err(e) = unescape_char(text) {
                         err = error_to_diagnostic_message(e, Mode::Char);
                     }
                 }
@@ -295,7 +295,7 @@ impl<'a> Converter<'a> {
                     let text = &self.res.text[self.offset + 2..][..len - 2];
                     let i = text.rfind('\'').unwrap();
                     let text = &text[..i];
-                    if let Err(e) = rustc_lexer::unescape::unescape_byte(text) {
+                    if let Err(e) = unescape_byte(text) {
                         err = error_to_diagnostic_message(e, Mode::Byte);
                     }
                 }
@@ -402,14 +402,14 @@ fn unescape_string_error_message(text: &str, mode: Mode) -> &'static str {
     let mut error_message = "";
     match mode {
         Mode::CStr => {
-            rustc_lexer::unescape::unescape_mixed(text, mode, &mut |_, res| {
+            unescape_mixed(text, mode, &mut |_, res| {
                 if let Err(e) = res {
                     error_message = error_to_diagnostic_message(e, mode);
                 }
             });
         }
         Mode::ByteStr | Mode::Str => {
-            rustc_lexer::unescape::unescape_unicode(text, mode, &mut |_, res| {
+            unescape_unicode(text, mode, &mut |_, res| {
                 if let Err(e) = res {
                     error_message = error_to_diagnostic_message(e, mode);
                 }

crates/syntax/Cargo.toml

@@ -17,6 +17,7 @@ either.workspace = true
 itertools.workspace = true
 rowan = "=0.15.15"
 rustc-hash.workspace = true
+rustc-literal-escaper = "0.0.1"
 indexmap.workspace = true
 smol_str.workspace = true
 triomphe.workspace = true

crates/syntax/src/ast/token_ext.rs

@@ -2,7 +2,7 @@
 
 use std::{borrow::Cow, num::ParseIntError};
 
-use rustc_lexer::unescape::{
+use rustc_literal_escaper::{
     unescape_byte, unescape_char, unescape_mixed, unescape_unicode, EscapeError, MixedUnit, Mode,
 };
 use stdx::always;

crates/syntax/src/lib.rs

@@ -19,13 +19,6 @@
 //! [RFC]: <https://github.com/rust-lang/rfcs/pull/2256>
 //! [Swift]: <https://github.com/apple/swift/blob/13d593df6f359d0cb2fc81cfaac273297c539455/lib/Syntax/README.md>
 
-#![cfg_attr(feature = "in-rust-tree", feature(rustc_private))]
-
-#[cfg(not(feature = "in-rust-tree"))]
-extern crate ra_ap_rustc_lexer as rustc_lexer;
-#[cfg(feature = "in-rust-tree")]
-extern crate rustc_lexer;
-
 mod parsing;
 mod ptr;
 mod syntax_error;
@@ -64,7 +57,7 @@ pub use rowan::{
     api::Preorder, Direction, GreenNode, NodeOrToken, SyntaxText, TextRange, TextSize,
     TokenAtOffset, WalkEvent,
 };
-pub use rustc_lexer::unescape;
+pub use rustc_literal_escaper as unescape;
 pub use smol_str::{format_smolstr, SmolStr, SmolStrBuilder, ToSmolStr};
 
 /// `Parse` is the result of the parsing: a syntax tree and a collection of

crates/syntax/src/validation.rs

@@ -5,7 +5,7 @@
 mod block;
 
 use rowan::Direction;
-use rustc_lexer::unescape::{self, unescape_mixed, unescape_unicode, Mode};
+use rustc_literal_escaper::{unescape_mixed, unescape_unicode, EscapeError, Mode};
 
 use crate::{
     algo,
@@ -44,8 +44,8 @@ pub(crate) fn validate(root: &SyntaxNode, errors: &mut Vec<SyntaxError>) {
     }
 }
 
-fn rustc_unescape_error_to_string(err: unescape::EscapeError) -> (&'static str, bool) {
+fn rustc_unescape_error_to_string(err: EscapeError) -> (&'static str, bool) {
-    use unescape::EscapeError as EE;
+    use rustc_literal_escaper::EscapeError as EE;
 
     #[rustfmt::skip]
     let err_message = match err {
@@ -127,7 +127,7 @@ fn validate_literal(literal: ast::Literal, acc: &mut Vec<SyntaxError>) {
     let text = token.text();
 
     // FIXME: lift this lambda refactor to `fn` (https://github.com/rust-lang/rust-analyzer/pull/2834#discussion_r366199205)
-    let mut push_err = |prefix_len, off, err: unescape::EscapeError| {
+    let mut push_err = |prefix_len, off, err: EscapeError| {
         let off = token.text_range().start() + TextSize::try_from(off + prefix_len).unwrap();
         let (message, is_err) = rustc_unescape_error_to_string(err);
         // FIXME: Emit lexer warnings