From 3d4a278f2ec2880bf82d3b0934938e57be928cad Mon Sep 17 00:00:00 2001
From: Stephen Chung <schungx@live.com>
Date: Wed, 22 Mar 2023 10:19:30 +0800
Subject: [PATCH] Remove ASTFlags::EMPTY.

---
 src/ast/expr.rs  |  6 +++---
 src/ast/flags.rs |  2 --
 src/ast/stmt.rs  |  6 +++---
 src/parser.rs    | 18 +++++++++---------
 4 files changed, 15 insertions(+), 17 deletions(-)

diff --git a/src/ast/expr.rs b/src/ast/expr.rs
index 6add6903..2f96af59 100644
--- a/src/ast/expr.rs
+++ b/src/ast/expr.rs
@@ -620,7 +620,7 @@ impl Expr {
             Self::Index(_, options, _) | Self::Dot(_, options, _) => *options,
 
             #[cfg(not(feature = "no_float"))]
-            Self::FloatConstant(..) => ASTFlags::NONE,
+            Self::FloatConstant(..) => ASTFlags::empty(),
 
             Self::DynamicConstant(..)
             | Self::BoolConstant(..)
@@ -638,10 +638,10 @@ impl Expr {
             | Self::MethodCall(..)
             | Self::InterpolatedString(..)
             | Self::Property(..)
-            | Self::Stmt(..) => ASTFlags::NONE,
+            | Self::Stmt(..) => ASTFlags::empty(),
 
             #[cfg(not(feature = "no_custom_syntax"))]
-            Self::Custom(..) => ASTFlags::NONE,
+            Self::Custom(..) => ASTFlags::empty(),
         }
     }
     /// Get the [position][Position] of the expression.
diff --git a/src/ast/flags.rs b/src/ast/flags.rs
index 7085ee54..f58eae68 100644
--- a/src/ast/flags.rs
+++ b/src/ast/flags.rs
@@ -41,8 +41,6 @@ bitflags! {
     /// _(internals)_ Bit-flags containing [`AST`][crate::AST] node configuration options.
     /// Exported under the `internals` feature only.
     pub struct ASTFlags: u8 {
-        /// No options for the [`AST`][crate::AST] node.
-        const NONE = 0b_0000_0000;
         /// The [`AST`][crate::AST] node is read-only.
         const CONSTANT = 0b_0000_0001;
         /// The [`AST`][crate::AST] node is exposed to the outside (i.e. public).
diff --git a/src/ast/stmt.rs b/src/ast/stmt.rs
index 9c67bcab..8487c4fb 100644
--- a/src/ast/stmt.rs
+++ b/src/ast/stmt.rs
@@ -779,13 +779,13 @@ impl Stmt {
             | Self::While(..)
             | Self::For(..)
             | Self::TryCatch(..)
-            | Self::Assignment(..) => ASTFlags::NONE,
+            | Self::Assignment(..) => ASTFlags::empty(),
 
             #[cfg(not(feature = "no_module"))]
-            Self::Import(..) | Self::Export(..) => ASTFlags::NONE,
+            Self::Import(..) | Self::Export(..) => ASTFlags::empty(),
 
             #[cfg(not(feature = "no_closure"))]
-            Self::Share(..) => ASTFlags::NONE,
+            Self::Share(..) => ASTFlags::empty(),
         }
     }
     /// Get the [position][Position] of this statement.
diff --git a/src/parser.rs b/src/parser.rs
index cbe69827..87e70e18 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -864,7 +864,7 @@ impl Engine {
                         let settings = settings.level_up()?;
                         // Recursively parse the indexing chain, right-binding each
                         let options = match token {
-                            Token::LeftBracket => ASTFlags::NONE,
+                            Token::LeftBracket => ASTFlags::empty(),
                             Token::QuestionBracket => ASTFlags::NEGATED,
                             _ => unreachable!("`[` or `?[`"),
                         };
@@ -1810,7 +1810,7 @@ impl Engine {
                 #[cfg(not(feature = "no_index"))]
                 (expr, token @ (Token::LeftBracket | Token::QuestionBracket)) => {
                     let opt = match token {
-                        Token::LeftBracket => ASTFlags::NONE,
+                        Token::LeftBracket => ASTFlags::empty(),
                         Token::QuestionBracket => ASTFlags::NEGATED,
                         _ => unreachable!("`[` or `?[`"),
                     };
@@ -1834,7 +1834,7 @@ impl Engine {
                     }
 
                     let op_flags = match op {
-                        Token::Period => ASTFlags::NONE,
+                        Token::Period => ASTFlags::empty(),
                         Token::Elvis => ASTFlags::NEGATED,
                         _ => unreachable!("`.` or `?.`"),
                     };
@@ -1842,7 +1842,7 @@ impl Engine {
                     let rhs =
                         self.parse_primary(input, state, lib, settings.level_up()?, options)?;
 
-                    Self::make_dot_expr(state, expr, rhs, ASTFlags::NONE, op_flags, tail_pos)?
+                    Self::make_dot_expr(state, expr, rhs, ASTFlags::empty(), op_flags, tail_pos)?
                 }
                 // Unknown postfix operator
                 (expr, token) => {
@@ -2141,7 +2141,7 @@ impl Engine {
             {
                 let options = options | parent_options;
                 x.rhs = Self::make_dot_expr(state, x.rhs, rhs, options, op_flags, op_pos)?;
-                Ok(Expr::Index(x, ASTFlags::NONE, pos))
+                Ok(Expr::Index(x, ASTFlags::empty(), pos))
             }
             // lhs.module::id - syntax error
             #[cfg(not(feature = "no_module"))]
@@ -2770,7 +2770,7 @@ impl Engine {
         let body = self.parse_block(input, state, lib, settings)?.into();
 
         let negated = match input.next().expect(NEVER_ENDS) {
-            (Token::While, ..) => ASTFlags::NONE,
+            (Token::While, ..) => ASTFlags::empty(),
             (Token::Until, ..) => ASTFlags::NEGATED,
             (.., pos) => {
                 return Err(
@@ -2966,7 +2966,7 @@ impl Engine {
         let export = if is_export {
             ASTFlags::EXPORTED
         } else {
-            ASTFlags::NONE
+            ASTFlags::empty()
         };
 
         let (existing, hit_barrier) = state.find_var(&name);
@@ -3433,7 +3433,7 @@ impl Engine {
                 if self.allow_looping() && settings.has_flag(ParseSettingFlags::BREAKABLE) =>
             {
                 let pos = eat_token(input, Token::Continue);
-                Ok(Stmt::BreakLoop(None, ASTFlags::NONE, pos))
+                Ok(Stmt::BreakLoop(None, ASTFlags::empty(), pos))
             }
             Token::Break
                 if self.allow_looping() && settings.has_flag(ParseSettingFlags::BREAKABLE) =>
@@ -3465,7 +3465,7 @@ impl Engine {
                     .next()
                     .map(|(token, pos)| {
                         let flags = match token {
-                            Token::Return => ASTFlags::NONE,
+                            Token::Return => ASTFlags::empty(),
                             Token::Throw => ASTFlags::BREAK,
                             token => unreachable!(
                                 "Token::Return or Token::Throw expected but gets {:?}",