public function testInvalidExpressions()
{
$Eval = new EvalMath();
$Eval->suppress_errors = true;
$result = $Eval->evaluate('()');
$this->assertEqual($Eval->getLastError(), 'Unexpected \')\'');
$result = $Eval->evaluate('1)');
$this->assertEqual($Eval->getLastError(), 'Unexpected \')\'');
$result = $Eval->evaluate('((');
$this->assertEqual($Eval->getLastError(), 'Expecting \')\'');
$result = $Eval->evaluate('2+3+');
$this->assertEqual($Eval->getLastError(), 'Operator \'+\' lacks operand');
$Eval->suppress_errors = false;
$this->expectError('Unexpected \',\'');
$result = $Eval->evaluate('a(1,2');
$this->assertEqual($Eval->getLastError(), 'Unexpected \',\'');
$this->assertIdentical(false, $result);
$this->expectError('Illegal character \'#\'');
$result = $Eval->evaluate('#');
$this->assertEqual($Eval->getLastError(), 'Illegal character \'#\'');
$this->assertIdentical(false, $result);
$this->expectError('Wrong number of arguments (3 given, 2 expected)');
$Eval->evaluate('f(x,y) = x+y');
$result = $Eval->evaluate('f(2,3,4)');
$this->assertEqual($Eval->getLastError(), 'Wrong number of arguments (3 given, 2 expected)');
$this->assertIdentical(false, $result);
$this->expectError('Too many arguments (2 given, 1 expected)');
$result = $Eval->evaluate('log(2,1)');
$this->assertEqual($Eval->getLastError(), 'Too many arguments (2 given, 1 expected)');
$this->assertIdentical(false, $result);
$this->expectError('Undefined variable \'z\' in function definition');
$result = $Eval->evaluate('f(x,y) = x+y+z');
$this->assertEqual($Eval->getLastError(), 'Undefined variable \'z\' in function definition');
$this->assertIdentical(false, $result);
unset($Eval);
}