feat: switch case

src/ast.rs

@@ -3,7 +3,7 @@
 use std::io;
 
 use crate::ast_token::{get_token_keyword, Token, get_token_literal};
-use crate::ast_node::{ Expression, NumberLiteral, StringLiteral, Statement, IdentifierLiteral, ExpressionStatement, PropertyAccessExpression, BinaryExpression, ConditionalExpression, CallExpression, Keywords, Parameter, BlockStatement, ReturnStatement, Declaration, PropertyAssignment, ObjectLiteral, ElementAccessExpression, FunctionDeclaration, PostfixUnaryExpression, PrefixUnaryExpression, AssignExpression, GroupExpression, VariableDeclaration, VariableDeclarationStatement, VariableFlag, ClassDeclaration, ClassMethodDeclaration, ArrayLiteral, ComputedPropertyName, IfStatement, ForStatement, BreakStatement, ContinueStatement, LabeledStatement, SwitchStatement, CaseBlocks, CaseClause};
+use crate::ast_node::{ Expression, NumberLiteral, StringLiteral, Statement, IdentifierLiteral, ExpressionStatement, PropertyAccessExpression, BinaryExpression, ConditionalExpression, CallExpression, Keywords, Parameter, BlockStatement, ReturnStatement, Declaration, PropertyAssignment, ObjectLiteral, ElementAccessExpression, FunctionDeclaration, PostfixUnaryExpression, PrefixUnaryExpression, AssignExpression, GroupExpression, VariableDeclaration, VariableDeclarationStatement, VariableFlag, ClassDeclaration, ClassMethodDeclaration, ArrayLiteral, ComputedPropertyName, IfStatement, ForStatement, BreakStatement, ContinueStatement, LabeledStatement, SwitchStatement, CaseClause};
 use crate::ast_utils::{get_hex_number_value, chars_to_string};
 pub struct AST {
  // 当前字符
@@ -232,9 +232,8 @@ impl AST{
  self.check_token_and_next(Token::LeftParenthesis);
  let condition = self.parse_expression();
  self.check_token_and_next(Token::RightParenthesis);
- println!("condition: {:?}", condition);
  self.check_token_and_next(Token::LeftBrace);
- let mut default = None;
+ let mut default_index: i32 = -1;
  let mut clauses: Vec<CaseClause> = vec![];
  loop {
  if self.token == Token::EOF || self.token == Token::RightBrace {
@@ -247,10 +246,10 @@ impl AST{
  };
  // parse case
  if self.token == Token::Default {
- if let Some(_) = default {
+ if default_index != -1 {
  // TODO: throw new error
  } else {
- is_default = true;
+ default_index = clauses.len() as i32;
  self.next();
  }
  } else {
@@ -265,23 +264,15 @@ impl AST{
  let statement = self.parse_statement();
  clause.statements.push(statement);
  }
-
- if is_default {
- default = Some(clause);
- } else {
- clauses.push(clause);
- }
+ clauses.push(clause);
  }
 
- println!("clauses {:?}", clauses);
 
  self.check_token_and_next(Token::RightBrace);
  Statement::Switch(SwitchStatement {
  condition,
- blocks: CaseBlocks {
- clauses,
- default
- }
+ clauses,
+ default_index
  })
  }
 
@@ -296,10 +287,9 @@ impl AST{
  if self.token == Token::Var || self.token == Token::Let {
  initializer = self.parse_variable_statement();
  } else if self.token != Token::Semicolon {
- initializer = Statement::Expression(ExpressionStatement { expression: self.parse_expression() })
+ initializer = Statement::Expression(ExpressionStatement { expression: self.parse_expression() });
  self.check_token_and_next(Token::Semicolon);
  }
- println!("xxx");
  let codition = self.parse_expression();
  self.check_token_and_next(Token::Semicolon);
  let incrementor = self.parse_expression();
@@ -729,7 +719,12 @@ impl AST{
  self.read();
  break;
  },
- _ => {}
+ _ => {
+ // EOF
+ if self.cur_char_index >= self.length {
+ break;
+ }
+ }
  };
  }
  continue;

src/ast_node.rs

@@ -127,13 +127,8 @@ pub struct IfStatement {
 #[derive(Debug, Clone, PartialEq)]
 pub struct SwitchStatement {
  pub condition: Expression,
- pub blocks: CaseBlocks
-}
-
-#[derive(Debug, Clone, PartialEq)]
-pub struct CaseBlocks {
- pub clauses: Vec<CaseClause>,
- pub default: Option<CaseClause>
+ pub clauses: Vec<CaseClause>,
+ pub default_index: i32
 }
 
 #[derive(Debug, Clone, PartialEq)]

src/context.rs

@@ -1,6 +1,6 @@
 use std::{rc::{Rc, Weak}, cell::RefCell, ops::Index};
 
-use crate::{ast::Program, ast_node::{Statement, Declaration, ObjectLiteral, AssignExpression, CallContext, ArrayLiteral, ClassType, ForStatement, VariableFlag, PostfixUnaryExpression, IdentifierLiteral, PrefixUnaryExpression}, ast_node::{Expression, CallExpression, Keywords, BinaryExpression}, value::{Value, ValueInfo, CallStatementOptions}, scope::{Scope, get_value_and_scope}, ast_token::Token, builtins::{object::{Object, Property, create_object}, function::{create_function, get_function_this}, global::{new_global_this, get_global_object}, array::create_array}};
+use crate::{ast::Program, ast_node::{Statement, Declaration, ObjectLiteral, AssignExpression, CallContext, ArrayLiteral, ClassType, ForStatement, VariableFlag, PostfixUnaryExpression, IdentifierLiteral, PrefixUnaryExpression, SwitchStatement, CaseClause}, ast_node::{Expression, CallExpression, Keywords, BinaryExpression}, value::{Value, ValueInfo, CallStatementOptions}, scope::{Scope, get_value_and_scope}, ast_token::Token, builtins::{object::{Object, Property, create_object}, function::{create_function, get_function_this}, global::{new_global_this, get_global_object}, array::create_array}};
 
 use super::ast::AST;
 pub struct Context {
@@ -87,7 +87,8 @@ impl Context {
  },
  Statement::Return(return_statement) => {
  (*result_value) = self.execute_expression(&return_statement.expression);
- (*last_statement_value) = result_value.clone()
+ (*last_statement_value) = result_value.clone();
+ (*interrupt) = Value::Interrupt(Token::Return, Expression::Unknown);
  },
  Statement::Function(_) => {
  // skip, 因为函数声明前置了
@@ -125,6 +126,9 @@ impl Context {
  Statement::While(for_statment) => {
  self.execute_for(for_statment, result_value, last_statement_value, interrupt, call_options)
  },
+ Statement::Switch(switch_statement) => {
+ self.execute_switch(switch_statement, result_value, last_statement_value, interrupt, call_options)
+ },
  Statement::Block(block) => {
  self.switch_scope(Some(Rc::clone(&self.cur_scope)));
  let result = self.call_block(&vec![], &block.statements);
@@ -410,7 +414,6 @@ impl Context {
  },
  _ => {}
  }
- println!("new_value2: {:?}", new_value);
  let value = Value::Number(new_value);
  operand_info.set_value(value.clone());
  value
@@ -524,6 +527,37 @@ impl Context {
  self.close_scope();
  }
 
+
+ // 执行循环
+ fn execute_switch(&mut self, switch_statment: &SwitchStatement, result_value: &mut Value, last_statement_value: &mut Value, interrupt: &mut Value, call_options: CallStatementOptions) {
+ let value = self.execute_expression(&switch_statment.condition);
+
+ let mut matched: i32 = switch_statment.default_index;
+ let clause_len = switch_statment.clauses.len();
+ for case_index in 0..clause_len {
+ if case_index as i32 == switch_statment.default_index {
+ continue;
+ }
+ let case = &switch_statment.clauses[case_index];
+ if let Some(condition) = &case.condition {
+ let case_value = self.execute_expression(condition);
+ if case_value.is_equal_to(&value, true) {
+ matched = case_index as i32;
+ }
+ }
+ }
+
+ for case_index in (matched as usize)..clause_len {
+ let case = &switch_statment.clauses[case_index];
+ let result = self.call_block(&vec![], &case.statements);
+ if let Value::Interrupt(token, _) = result.2 {
+ if token == Token::Break {
+ break;
+ }
+ }
+ }
+ }
+
  fn new_object(&mut self, expression: &ObjectLiteral) -> Value {
  // 获取 object 实例
  let object = create_object(&self.global,ClassType::Array, None);

tests/confitional_test.rs

@@ -20,18 +20,20 @@ fn run_if_else() {
 fn run_switch_case() {
  let mut jsi = JSI::new();
  let result = jsi.run(String::from("\
+ let res;
  switch('a') {
  case 'a':
- 1;
+ res = 1;
  break;
  case 'b':
- 2;
+ res = 2;
  break;
  default:
- 3;
+ res = 3;
  break;
- }"));
- assert_eq!(result , Value::Number(2f64));
+ }
+ res"));
+ assert_eq!(result , Value::Number(1f64));
 }
 
 #[test]
@@ -40,10 +42,10 @@ fn run_for() {
  let result = jsi.run(String::from("\
  let a = [];
  let i;
- // for(i = 0; i < 3; i++) {
- //  a.push(++i);
- // }
- // a.join(':')"));
+ for(i = 0; i < 3; i++) {
+ a.push(++i);
+ }
+ a.join(':')"));
  assert_eq!(result , Value::String(String::from("1:3")));
 }