/// <summary>
/// create and expression ( operator ";" )
/// </summary>
/// <param name="visitor"></param>
/// <param name="context"></param>
/// <typeparam name="T"></typeparam>
/// <returns></returns>
public static Expression <Func <T, bool> > GetAndExpression <T>(
IRSqlQueryVisitor <Expression <Func <T, bool> > > visitor, RSqlQueryParser.AndContext context)
{
if (visitor == null)
{
throw new ArgumentNullException(nameof(visitor));
}
if (context == null)
{
throw new ArgumentNullException(nameof(context));
}
var right = context.constraint()[0].Accept(visitor);
if (context.constraint().Length == 1)
{
return(right);
}
for (var i = 1; i < context.constraint().Length; i++)
{
var left = context.constraint()[i].Accept(visitor);
right = Expression.Lambda <Func <T, bool> >(Expression.And(left.Body, right.Body), left.Parameters);
}
return(right);
}
public void ShouldBeGetAndExpressionThrowArgumentNullExceptionTest()
{
// visitor = null
var context = new RSqlQueryParser.AndContext(null, 0);
this.Invoking(a => RSqlQueryExpressionHelper.GetAndExpression <Customer>(null, context))
.Should().Throw <ArgumentNullException>();
var visitor = new RSqlDefaultQueryVisitor <Customer>(JsonNamingPolicy.CamelCase);
// context = null
this.Invoking(a => RSqlQueryExpressionHelper.GetAndExpression(visitor, null))
.Should().Throw <ArgumentNullException>();
}
/// <summary>
/// Visit a parse tree produced by <see cref="RSqlQueryParser.and"/>.
/// <para>
/// The default implementation returns the result of calling <see cref="AbstractParseTreeVisitor{Result}.VisitChildren(IRuleNode)"/>
/// on <paramref name="context"/>.
/// </para>
/// </summary>
/// <param name="context">The parse tree.</param>
/// <return>The visitor result.</return>
public virtual Result VisitAnd([NotNull] RSqlQueryParser.AndContext context)
{
return(VisitChildren(context));
}
/// <summary>
/// visit a and expression
/// </summary>
/// <param name="context"></param>
/// <returns></returns>
public override Expression <Func <T, bool> > VisitAnd(RSqlQueryParser.AndContext context)
{
return(RSqlQueryExpressionHelper.GetAndExpression(this, context));
}
/// <summary>
/// Enter a parse tree produced by <see cref="RSqlQueryParser.and"/>.
/// <para>The default implementation does nothing.</para>
/// </summary>
/// <param name="context">The parse tree.</param>
public virtual void EnterAnd([NotNull] RSqlQueryParser.AndContext context)
{
}
