Merge pull request RustPython#3879 from key262yek/update-assign-del

Fix failure test_assign_del() in Lib/test/test_syntax.py

Author: youknowone

Lib/test/test_syntax.py

@@ -1330,8 +1330,6 @@ def test_curly_brace_after_primary_raises_immediately(self):
     def test_assign_call(self):
         self._check_error("f() = 1", "assign")
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_assign_del(self):
         self._check_error("del (,)", "invalid syntax")
         self._check_error("del 1", "cannot delete literal")

ast/src/impls.rs

@@ -20,7 +20,14 @@ impl<U> ExprKind<U> {
                 | Constant::Complex { .. }
                 | Constant::Bytes(_) => "literal",
                 Constant::Tuple(_) => "tuple",
-                Constant::Bool(_) | Constant::None => "keyword",
+                Constant::Bool(b) => {
+                    if *b {
+                        "True"
+                    } else {
+                        "False"
+                    }
+                }
+                Constant::None => "None",
                 Constant::Ellipsis => "ellipsis",
             },
             ExprKind::List { .. } => "list",

compiler/src/compile.rs

@@ -847,11 +847,14 @@ impl Compiler {
                 self.compile_expression(slice)?;
                 self.emit(Instruction::DeleteSubscript);
             }
-            ast::ExprKind::Tuple { elts, .. } => {
+            ast::ExprKind::Tuple { elts, .. } | ast::ExprKind::List { elts, .. } => {
                 for element in elts {
                     self.compile_delete(element)?;
                 }
             }
+            ast::ExprKind::BinOp { .. } | ast::ExprKind::UnaryOp { .. } => {
+                return Err(self.error(CompileErrorType::Delete("expression")))
+            }
             _ => return Err(self.error(CompileErrorType::Delete(expression.node.name()))),
         }
         Ok(())

compiler/src/error.rs

@@ -40,13 +40,13 @@ pub enum CompileErrorType {
 impl fmt::Display for CompileErrorType {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match self {
-            CompileErrorType::Assign(target) => write!(f, "can't assign to {}", target),
-            CompileErrorType::Delete(target) => write!(f, "can't delete {}", target),
+            CompileErrorType::Assign(target) => write!(f, "cannot assign to {}", target),
+            CompileErrorType::Delete(target) => write!(f, "cannot delete {}", target),
             CompileErrorType::SyntaxError(err) => write!(f, "{}", err.as_str()),
             CompileErrorType::MultipleStarArgs => {
                 write!(f, "two starred expressions in assignment")
             }
-            CompileErrorType::InvalidStarExpr => write!(f, "can't use starred expression here"),
+            CompileErrorType::InvalidStarExpr => write!(f, "cannot use starred expression here"),
             CompileErrorType::InvalidBreak => write!(f, "'break' outside loop"),
             CompileErrorType::InvalidContinue => write!(f, "'continue' outside loop"),
             CompileErrorType::InvalidReturn => write!(f, "'return' outside function"),

parser/src/python.lalrpop

@@ -6,7 +6,7 @@
 use crate::ast;
 use crate::fstring::parse_located_fstring;
 use crate::function::{ArgumentList, parse_args, parse_params};
-use crate::error::LexicalError;
+use crate::error::{LexicalError, LexicalErrorType};
 use crate::lexer;
 use crate::token::StringKind;
 
@@ -999,12 +999,29 @@ Atom: ast::Expr = {
             node: ast::ExprKind::ListComp { elt: Box::new(elt), generators }
         }
     },
-    <location:@L> "(" <elements:TestOrStarNamedExprList?> ")" => {
-        elements.unwrap_or(ast::Expr {
-             location,
-             custom: (),
-             node: ast::ExprKind::Tuple { elts: Vec::new(), ctx: ast::ExprContext::Load }
-        })
+    <location:@L> "(" <elements:TestOrStarNamedExprList?> ")" =>? {
+        match elements {
+            Some(elt) => {
+                match elt.node {
+                    ast::ExprKind::Starred { .. } => {
+                        Err(LexicalError{
+                            error : LexicalErrorType::OtherError("cannot use starred expression here".to_string()),
+                            location,
+                        }.into())
+                    },
+                    _ => {
+                        Ok(elt)
+                    }
+                }
+            },
+            None => {
+                Ok(ast::Expr {
+                     location,
+                     custom: (),
+                     node: ast::ExprKind::Tuple { elts: Vec::new(), ctx: ast::ExprContext::Load }
+                })
+            }
+        }
     },
     "(" <e:YieldExpr> ")" => e,
     <location:@L> "(" <elt:Test> <generators:CompFor> ")" => {
@@ -1014,6 +1031,12 @@ Atom: ast::Expr = {
             node: ast::ExprKind::GeneratorExp { elt: Box::new(elt), generators }
         }
     },
+    "(" <location:@L> "**" <e:Expression> ")" =>? {
+        Err(LexicalError{
+            error : LexicalErrorType::OtherError("cannot use double starred expression here".to_string()),
+            location,
+        }.into())
+    },
     <location:@L> "{" <e:DictLiteralValues?> "}" => {
         let (keys, values) = e.unwrap_or_default();
         ast::Expr {
@@ -1082,7 +1105,7 @@ ExpressionList: ast::Expr = {
 };
 
 ExpressionList2: Vec<ast::Expr> = {
-    <elements:OneOrMore<Expression>> ","? => elements,
+    <elements:OneOrMore<ExpressionOrStarExpression>> ","? => elements,
 };
 
 // A test list is one of: