Auto merge of rust-lang#109128 - chenyukang:yukang/remove-type-ascription, r=estebank

Remove type ascription from parser and diagnostics

Mostly based on rust-lang#106826

Part of rust-lang#101728

r? `@estebank`

Author: bors

clippy_utils/src/sugg.rs

@@ -163,7 +163,8 @@ impl<'a> Sugg<'a> {
                 get_snippet(rhs.span),
             ),
             hir::ExprKind::Cast(lhs, ty) => Sugg::BinOp(AssocOp::As, get_snippet(lhs.span), get_snippet(ty.span)),
-            hir::ExprKind::Type(lhs, ty) => Sugg::BinOp(AssocOp::Colon, get_snippet(lhs.span), get_snippet(ty.span)),
+            //FIXME(chenyukang), remove this after type ascription is removed from AST
+            hir::ExprKind::Type(lhs, ty) => Sugg::BinOp(AssocOp::As, get_snippet(lhs.span), get_snippet(ty.span)),
         }
     }
 
@@ -258,8 +259,9 @@ impl<'a> Sugg<'a> {
                 snippet_with_context(cx, lhs.span, ctxt, default, app).0,
                 snippet_with_context(cx, ty.span, ctxt, default, app).0,
             ),
+            //FIXME(chenyukang), remove this after type ascription is removed from AST
             ast::ExprKind::Type(ref lhs, ref ty) => Sugg::BinOp(
-                AssocOp::Colon,
+                AssocOp::As,
                 snippet_with_context(cx, lhs.span, ctxt, default, app).0,
                 snippet_with_context(cx, ty.span, ctxt, default, app).0,
             ),
@@ -392,7 +394,6 @@ fn binop_to_string(op: AssocOp, lhs: &str, rhs: &str) -> String {
         AssocOp::As => format!("{lhs} as {rhs}"),
         AssocOp::DotDot => format!("{lhs}..{rhs}"),
         AssocOp::DotDotEq => format!("{lhs}..={rhs}"),
-        AssocOp::Colon => format!("{lhs}: {rhs}"),
     }
 }
 
@@ -602,13 +603,13 @@ enum Associativity {
 #[must_use]
 fn associativity(op: AssocOp) -> Associativity {
     use rustc_ast::util::parser::AssocOp::{
-        Add, As, Assign, AssignOp, BitAnd, BitOr, BitXor, Colon, Divide, DotDot, DotDotEq, Equal, Greater,
+        Add, As, Assign, AssignOp, BitAnd, BitOr, BitXor, Divide, DotDot, DotDotEq, Equal, Greater,
         GreaterEqual, LAnd, LOr, Less, LessEqual, Modulus, Multiply, NotEqual, ShiftLeft, ShiftRight, Subtract,
     };
 
     match op {
         Assign | AssignOp(_) => Associativity::Right,
-        Add | BitAnd | BitOr | BitXor | LAnd | LOr | Multiply | As | Colon => Associativity::Both,
+        Add | BitAnd | BitOr | BitXor | LAnd | LOr | Multiply | As => Associativity::Both,
         Divide | Equal | Greater | GreaterEqual | Less | LessEqual | Modulus | NotEqual | ShiftLeft | ShiftRight
         | Subtract => Associativity::Left,
         DotDot | DotDotEq => Associativity::None,