public void CanEvaluatePrimitives()
{
var env = new StandardEnvironment();
env.DefineValue("foo", "foo");
env.DefineValue("_foo_bar", "_foo_bar");
// Symbols
Assert.AreEqual("foo", Evaluate("foo", env));
Assert.AreEqual("foo", Evaluate(" foo ", env));
Assert.AreEqual("_foo_bar", Evaluate("_foo_bar", env));
// Strings
Assert.AreEqual("foo'bar", Evaluate("'foo''bar'", env));
Assert.AreEqual("foo\"bar\"\n\'/\\", Evaluate(@"""foo\""bar\""\n\'\/\\""", env));
// Numbers
Assert.AreEqual(123, Evaluate("123"));
Assert.AreEqual(1.23, Evaluate("1.23"));
Assert.AreEqual(2.7e-5, Evaluate("2.7e-5"));
// null and Booleans
Assert.AreEqual(null, Evaluate("null"));
Assert.AreEqual(false, Evaluate("false"));
Assert.AreEqual(true, Evaluate("true"));
// Excessive parens...
Assert.AreEqual(42, Evaluate("(((23+19)))"));
}
public void CanEvaluateConditionalOperator()
{
Assert.AreEqual("T", Evaluate("true ? 'T' : 'F'"));
Assert.AreEqual("F", Evaluate("false ? 'T' : 'F'"));
Assert.AreEqual(null, Evaluate("null ? 'T' : 'F'"));
var env = new StandardEnvironment();
env.DefineValue("xyzzy", "Magic");
env.DefineValue("d", 5);
Assert.AreEqual(5, Evaluate("xyzzy ? length(xyzzy) : -1", env));
Assert.AreEqual("Fri", Evaluate("d=0 ? 'Sun' : d=1 ? 'Mon' : d=2 ? 'Tue' : d=3 ? 'Wed' : d=4 ? 'Thu' : d=5 ? 'Fri' : d=6 ? 'Sat' : null", env));
}
public void CanEvaluateUnaryOps()
{
Assert.AreEqual(5, Evaluate("+5"));
Assert.AreEqual(-5, Evaluate("+-5"));
Assert.AreEqual(25, Evaluate("+ + +25"));
Assert.AreEqual(-0.2, Evaluate(" - 0.2 "));
Assert.AreEqual(-0.2, Evaluate("- - -0.2"));
Assert.AreEqual(-1.2e-03, Evaluate("-1.2e-03"));
Assert.AreEqual(false, Evaluate("not true"));
Assert.AreEqual(true, Evaluate("not not true"));
Assert.AreEqual(true, Evaluate("not not 5"));
var env = new StandardEnvironment();
env.DefineValue("foo", 42.0);
Assert.AreEqual(42.0, Evaluate("foo", env));
Assert.AreEqual(false, Evaluate("not foo", env));
Assert.AreEqual(true, Evaluate("not not foo", env));
Assert.AreEqual(false, Evaluate("not not not foo", env));
Assert.AreEqual(5, Evaluate("+ +5"));
Catch(() => Evaluate("++5"));
Assert.AreEqual(25, Evaluate("- - 25"));
Catch(() => Evaluate("-- 25")); // -- is one token
}
public void CanLookupPrecedence()
{
// Lookup precedence for unqualified names:
// defined value < standard function < field value
// Qualified names are always looked up on a row of fields
// defined with the qualifier. CONCAT is a standard function.
var env = new StandardEnvironment();
var row = new ConstantValueTestRow("row", "CONCAT", "FOO");
const string qualifier = "qualifier";
Assert.Catch <EvaluationException>(() => env.Lookup("FOO", null));
Assert.IsInstanceOf <Function>(env.Lookup("CONCAT", null));
Assert.Catch <EvaluationException>(() => env.Lookup("CONCAT", qualifier));
env.DefineFields(row, qualifier);
Assert.AreEqual("row", env.Lookup("FOO", null));
Assert.IsInstanceOf <Function>(env.Lookup("CONCAT", null));
Assert.AreEqual("row", env.Lookup("CONCAT", qualifier));
env.DefineValue("FOO", "foo");
env.DefineValue("CONCAT", "value");
Assert.AreEqual("foo", env.Lookup("FOO", null));
Assert.AreEqual("value", env.Lookup("CONCAT", null));
Assert.AreEqual("row", env.Lookup("CONCAT", qualifier));
env.ForgetValue("CONCAT");
env.ForgetValue("FOO");
Assert.AreEqual("row", env.Lookup("FOO", null));
Assert.IsInstanceOf <Function>(env.Lookup("CONCAT", null));
Assert.AreEqual("row", env.Lookup("CONCAT", qualifier));
env.ForgetFields("qualifier");
Assert.Catch <EvaluationException>(() => env.Lookup("FOO", null));
Assert.IsInstanceOf <Function>(env.Lookup("CONCAT", null));
Assert.Catch <EvaluationException>(() => env.Lookup("CONCAT", qualifier));
}
public void CanLookupIgnoreCase()
{
var envIgnoreCase = new StandardEnvironment();
envIgnoreCase.DefineValue("foo", "bar");
Assert.AreEqual("bar", envIgnoreCase.Lookup("foo", null));
Assert.AreEqual("bar", envIgnoreCase.Lookup("FOO", null));
var ex1 = Assert.Catch <EvaluationException>(() => envIgnoreCase.Lookup("foo", "qualifier"));
Console.WriteLine(@"Expected exception: {0}", ex1.Message);
Assert.IsInstanceOf(typeof(Function), envIgnoreCase.Lookup("TRIM", null));
Assert.IsInstanceOf(typeof(Function), envIgnoreCase.Lookup("Trim", null));
}
public void CanEvaluateNullCoalescingOperator()
{
Assert.AreEqual("foo", Evaluate("'foo' ?? 'bar'"));
Assert.AreEqual("bar", Evaluate("null ?? 'bar'"));
// Here's how ?? is different from || (logical or):
Assert.AreEqual(false, Evaluate("false ?? 'bar'"));
Assert.AreEqual(true, Evaluate("false or 'bar'")); // "bar"
// ?? binds tighter than ?:
var env = new StandardEnvironment();
env.DefineValue("nothing", null);
Assert.AreEqual("alt", Evaluate("nothing ?? false ? null ?? 'consequent' : 'alt' ?? 'alternative'", env));
}
public void CanLookupQualified()
{
var env = new StandardEnvironment(false);
env.DefineValue("foo", "bar");
Assert.AreEqual("bar", env.Lookup("foo", null));
var ex1 = Assert.Catch <EvaluationException>(() => env.Lookup("foo", "qualifier"));
Console.WriteLine(@"Expected exception: {0}", ex1.Message);
Assert.IsInstanceOf <Function>(env.Lookup("TRIM", null));
var ex2 = Assert.Catch <EvaluationException>(() => env.Lookup("TRIM", "qualifier"));
Console.WriteLine(@"Expected exception: {0}", ex2.Message);
}
public void CanEvaluateArithmetic()
{
Assert.AreEqual(-7, Evaluate(" 1 - 3 - 5 "));
Assert.AreEqual(3, Evaluate("1-(3-5)"));
Assert.AreEqual(2, Evaluate("1-2+3"));
Assert.AreEqual(-6.28, Evaluate("3.14*-2")); // *- is two tokens!
Assert.AreEqual(0, Evaluate("12-3*4"));
Assert.AreEqual(36, Evaluate("(12-3)*4"));
var env = new StandardEnvironment();
env.DefineValue("LB", 0.46);
Assert.IsTrue(Math.Abs((double)Evaluate("LB/2", env)) - 0.23 < double.Epsilon);
Assert.IsTrue(Math.Abs((double)Evaluate("0.5*LB", env)) - 0.23 < double.Epsilon);
}
public void CanCaseInSensitive()
{
const string name = "fAlSe";
// When ignoring case, "fAlSe" will be recognized as the built-in value false:
var envIgnoreCase = new StandardEnvironment();
envIgnoreCase.DefineValue(name, "TheEnv");
Assert.AreEqual(false, Dump(ExpressionEvaluator.Create("fAlSe")).Evaluate(envIgnoreCase));
// When respecting case, "fAlSe" is just a name to be looked up in the environment:
var envRespectCase = new StandardEnvironment(false);
envRespectCase.DefineValue(name, "TheEnv");
Assert.AreEqual("TheEnv", Dump(ExpressionEvaluator.Create("fAlSe", false)).Evaluate(envRespectCase));
}