sebastienros.jint/Jint/Runtime/Interpreter/Statements/JintWithStatement.cs

using Jint.Runtime.Environments;
using Jint.Runtime.Interpreter.Expressions;

namespace Jint.Runtime.Interpreter.Statements;

/// <summary>
/// http://www.ecma-international.org/ecma-262/5.1/#sec-12.10
/// </summary>
internal sealed class JintWithStatement : JintStatement<WithStatement>
{
    private ProbablyBlockStatement _body;
    private JintExpression _object = null!;

    public JintWithStatement(WithStatement statement) : base(statement)
    {
    }

    protected override void Initialize(EvaluationContext context)
    {
        _body = new ProbablyBlockStatement(_statement.Body);
        _object = JintExpression.Build(_statement.Object);
    }

    protected override Completion ExecuteInternal(EvaluationContext context)
    {
        var jsValue = _object.GetValue(context);
        var engine = context.Engine;
        var obj = TypeConverter.ToObject(engine.Realm, jsValue);
        var oldEnv = engine.ExecutionContext.LexicalEnvironment;
        var newEnv = JintEnvironment.NewObjectEnvironment(engine, obj, oldEnv, provideThis: true, withEnvironment: true);
        engine.UpdateLexicalEnvironment(newEnv);

        Completion c;
        try
        {
            c = _body.Execute(context);
        }
        catch (JavaScriptException e)
        {
            c = new Completion(CompletionType.Throw, e.Error, _statement);
        }
        finally
        {
            engine.UpdateLexicalEnvironment(oldEnv);
        }

        return c;
    }
}