Introduce hir::Lit not keeping the original token

Author: petrochenkov

src/librustc/hir/lowering.rs

@@ -4124,7 +4124,7 @@ impl<'a> LoweringContext<'a> {
                 let ohs = P(self.lower_expr(ohs));
                 hir::ExprKind::Unary(op, ohs)
             }
-            ExprKind::Lit(ref l) => hir::ExprKind::Lit((*l).clone()),
+            ExprKind::Lit(ref l) => hir::ExprKind::Lit(respan(l.span, l.node.clone())),
             ExprKind::Cast(ref expr, ref ty) => {
                 let expr = P(self.lower_expr(expr));
                 hir::ExprKind::Cast(expr, self.lower_ty(ty, ImplTraitContext::disallowed()))

src/librustc/hir/mod.rs

@@ -20,7 +20,7 @@ use syntax_pos::{Span, DUMMY_SP, symbol::InternedString};
 use syntax::source_map::Spanned;
 use rustc_target::spec::abi::Abi;
 use syntax::ast::{self, CrateSugar, Ident, Name, NodeId, AsmDialect};
-use syntax::ast::{Attribute, Label, Lit, StrStyle, FloatTy, IntTy, UintTy};
+use syntax::ast::{Attribute, Label, LitKind, StrStyle, FloatTy, IntTy, UintTy};
 use syntax::attr::{InlineAttr, OptimizeAttr};
 use syntax::ext::hygiene::SyntaxContext;
 use syntax::ptr::P;
@@ -1331,6 +1331,9 @@ impl BodyOwnerKind {
     }
 }
 
+/// A literal.
+pub type Lit = Spanned<LitKind>;
+
 /// A constant (expression) that's not an item or associated item,
 /// but needs its own `DefId` for type-checking, const-eval, etc.
 /// These are usually found nested inside types (e.g., array lengths)
@@ -1353,7 +1356,7 @@ pub struct Expr {
 
 // `Expr` is used a lot. Make sure it doesn't unintentionally get bigger.
 #[cfg(target_arch = "x86_64")]
-static_assert!(MEM_SIZE_OF_EXPR: std::mem::size_of::<Expr>() == 80);
+static_assert!(MEM_SIZE_OF_EXPR: std::mem::size_of::<Expr>() == 72);
 
 impl Expr {
     pub fn precedence(&self) -> ExprPrecedence {

src/librustc/hir/print.rs

@@ -15,6 +15,7 @@ use crate::hir;
 use crate::hir::{PatKind, GenericBound, TraitBoundModifier, RangeEnd};
 use crate::hir::{GenericParam, GenericParamKind, GenericArg};
 
+use std::ascii;
 use std::borrow::Cow;
 use std::cell::Cell;
 use std::io::{self, Write, Read};
@@ -1335,6 +1336,64 @@ impl<'a> State<'a> {
         self.print_expr_maybe_paren(expr, parser::PREC_PREFIX)
     }
 
+    fn print_literal(&mut self, lit: &hir::Lit) -> io::Result<()> {
+        self.maybe_print_comment(lit.span.lo())?;
+        if let Some(ltrl) = self.next_lit(lit.span.lo()) {
+            return self.writer().word(ltrl.lit.clone());
+        }
+        match lit.node {
+            hir::LitKind::Str(st, style) => self.print_string(&st.as_str(), style),
+            hir::LitKind::Err(st) => {
+                let st = st.as_str().escape_debug().to_string();
+                let mut res = String::with_capacity(st.len() + 2);
+                res.push('\'');
+                res.push_str(&st);
+                res.push('\'');
+                self.writer().word(res)
+            }
+            hir::LitKind::Byte(byte) => {
+                let mut res = String::from("b'");
+                res.extend(ascii::escape_default(byte).map(|c| c as char));
+                res.push('\'');
+                self.writer().word(res)
+            }
+            hir::LitKind::Char(ch) => {
+                let mut res = String::from("'");
+                res.extend(ch.escape_default());
+                res.push('\'');
+                self.writer().word(res)
+            }
+            hir::LitKind::Int(i, t) => {
+                match t {
+                    ast::LitIntType::Signed(st) => {
+                        self.writer().word(st.val_to_string(i as i128))
+                    }
+                    ast::LitIntType::Unsigned(ut) => {
+                        self.writer().word(ut.val_to_string(i))
+                    }
+                    ast::LitIntType::Unsuffixed => {
+                        self.writer().word(i.to_string())
+                    }
+                }
+            }
+            hir::LitKind::Float(ref f, t) => {
+                self.writer().word(format!("{}{}", &f, t.ty_to_string()))
+            }
+            hir::LitKind::FloatUnsuffixed(ref f) => self.writer().word(f.as_str().to_string()),
+            hir::LitKind::Bool(val) => {
+                if val { self.writer().word("true") } else { self.writer().word("false") }
+            }
+            hir::LitKind::ByteStr(ref v) => {
+                let mut escaped: String = String::new();
+                for &ch in v.iter() {
+                    escaped.extend(ascii::escape_default(ch)
+                                         .map(|c| c as char));
+                }
+                self.writer().word(format!("b\"{}\"", escaped))
+            }
+        }
+    }
+
     pub fn print_expr(&mut self, expr: &hir::Expr) -> io::Result<()> {
         self.maybe_print_comment(expr.span.lo())?;
         self.print_outer_attributes(&expr.attrs)?;

src/librustc/ich/impls_syntax.rs

@@ -181,6 +181,8 @@ impl_stable_hash_for!(enum ::syntax::ast::LitKind {
     Bool(value)
 });
 
+impl_stable_hash_for_spanned!(::syntax::ast::LitKind);
+
 impl_stable_hash_for!(enum ::syntax::ast::IntTy { Isize, I8, I16, I32, I64, I128 });
 impl_stable_hash_for!(enum ::syntax::ast::UintTy { Usize, U8, U16, U32, U64, U128 });
 impl_stable_hash_for!(enum ::syntax::ast::FloatTy { F32, F64 });

src/librustc_lint/types.rs

@@ -62,7 +62,7 @@ impl TypeLimits {
 /// Returns `true` iff the lint was overridden.
 fn lint_overflowing_range_endpoint<'a, 'tcx>(
     cx: &LateContext<'a, 'tcx>,
-    lit: &ast::Lit,
+    lit: &hir::Lit,
     lit_val: u128,
     max: u128,
     expr: &'tcx hir::Expr,
@@ -132,7 +132,7 @@ fn uint_ty_range(uint_ty: ast::UintTy) -> (u128, u128) {
     }
 }
 
-fn get_bin_hex_repr(cx: &LateContext<'_, '_>, lit: &ast::Lit) -> Option<String> {
+fn get_bin_hex_repr(cx: &LateContext<'_, '_>, lit: &hir::Lit) -> Option<String> {
     let src = cx.sess().source_map().span_to_snippet(lit.span).ok()?;
     let firstch = src.chars().next()?;
 
@@ -249,7 +249,7 @@ fn lint_int_literal<'a, 'tcx>(
     cx: &LateContext<'a, 'tcx>,
     type_limits: &TypeLimits,
     e: &'tcx hir::Expr,
-    lit: &ast::Lit,
+    lit: &hir::Lit,
     t: ast::IntTy,
     v: u128,
 ) {
@@ -301,7 +301,7 @@ fn lint_int_literal<'a, 'tcx>(
 fn lint_uint_literal<'a, 'tcx>(
     cx: &LateContext<'a, 'tcx>,
     e: &'tcx hir::Expr,
-    lit: &ast::Lit,
+    lit: &hir::Lit,
     t: ast::UintTy,
 ) {
     let uint_type = if let ast::UintTy::Usize = t {
@@ -363,7 +363,7 @@ fn lint_literal<'a, 'tcx>(
     cx: &LateContext<'a, 'tcx>,
     type_limits: &TypeLimits,
     e: &'tcx hir::Expr,
-    lit: &ast::Lit,
+    lit: &hir::Lit,
 ) {
     match cx.tables.node_type(e.hir_id).sty {
         ty::Int(t) => {

src/librustc_typeck/check/mod.rs

@@ -3084,7 +3084,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
 
     // AST fragment checking
     fn check_lit(&self,
-                 lit: &ast::Lit,
+                 lit: &hir::Lit,
                  expected: Expectation<'tcx>)
                  -> Ty<'tcx>
     {

src/libsyntax/ast.rs

@@ -1352,7 +1352,7 @@ pub enum StrStyle {
 }
 
 /// A literal.
-#[derive(Clone, RustcEncodable, RustcDecodable, Debug, Hash, PartialEq)]
+#[derive(Clone, RustcEncodable, RustcDecodable, Debug)]
 pub struct Lit {
     pub node: LitKind,
     pub token: token::Lit,