public bool TryGetHint(ExpressionParser parser, Expression expression, out string hint)
{
var methE = expression as MethodCallExpression;
if (methE != null)
{
if (methE.Method == ObjectEqualsMethodInfo)
{
var left = parser.DynamicInvoke(methE.Arguments[0]);
var right = parser.DynamicInvoke(methE.Arguments[1]);
if (left is Delegate || right is Delegate)
{
if (CheckArgument(parser, methE, true, out hint))
{
return true;
}
if (CheckArgument(parser, methE, false, out hint))
{
return true;
}
hint = ", this is a suspicious comparison";
return true;
}
}
}
hint = null;
return false;
}
public void ParseStringConstant()
{
Expression<Func<string>> f = () => "foo";
var p = new ExpressionParser(f.Body);
ConstantNode constantNode = p.Parse() as ConstantNode;
Assert.AreEqual("\"foo\"", constantNode.Text);
}
static bool CheckArgument(ExpressionParser parser, MethodCallExpression methE, bool left, out string hint)
{
int ix1 = left ? 0 : 1;
int ix2 = left ? 1 : 0;
if (typeof (Delegate).IsAssignableFrom(methE.Arguments[ix1].Type))
{
object leftR;
try
{
leftR = parser.DynamicInvoke(Expression.Invoke(methE.Arguments[ix1]));
}
catch (InvalidOperationException) // delegate needs arguments
{
hint = null;
return false;
}
if (Equals(leftR, parser.DynamicInvoke(methE.Arguments[ix2])))
{
hint = string.Format(", but would have been True if you had invoked '{0}'",
NodeFormatter.PrettyPrint(parser.Parse(methE.Arguments[ix1])));
return true;
}
}
hint = null;
return false;
}
public void ParsePrimitiveConstant()
{
Expression<Func<int>> f = () => 5;
var p = new ExpressionParser(f.Body);
ConstantNode constantNode = p.Parse() as ConstantNode;
Assert.AreEqual("5", constantNode.Text);
}
public void ParsePrimitiveStaticField()
{
Expression<Func<int>> f = () => field;
var p = new ExpressionParser(f.Body);
ConstantNode constantNode = p.Parse() as ConstantNode;
Assert.AreEqual("field", constantNode.Text);
Assert.AreEqual("5", constantNode.Value);
}
public void ParseMember()
{
int x = 5;
Expression<Func<int>> f = () => x;
var p = new ExpressionParser(f.Body);
Node constantNode = p.Parse();
Assert.AreEqual(new ConstantNode {Text = "x", Value = "5"}, constantNode);
}
public void ShouldTriggerOnTotalMisusageWithObjectEquals_Right()
{
var hint = new TimeSpanTotalMistakesHint();
Expression<Func<bool>> x = () => Equals(63, TimeSpan.FromMinutes(63).Minutes);
var p = new ExpressionParser(x.Body);
string description;
Assert.IsTrue(hint.TryGetHint(p, x.Body, out description));
Assert.IsNotNull(description);
}
public void DoesntTriggerIfNotComparesEqual()
{
var hint = new MethodEqualsInsteadOfOperatorEqualsHint();
Expression<Func<bool>> exp = () => new NeverEqual() == new NeverEqual();
var p = new ExpressionParser(exp.Body);
string description;
Assert.IsFalse(hint.TryGetHint(p, exp.Body, out description));
Assert.IsNull(description);
}
public void TriggersIfComparesEqual()
{
var hint = new MethodEqualsInsteadOfOperatorEqualsHint();
Expression<Func<bool>> exp = () => new AlwaysEqual() == new AlwaysEqual();
var p = new ExpressionParser(exp.Body);
string description;
Assert.IsTrue(hint.TryGetHint(p, exp.Body, out description));
Assert.IsNotNull(description);
}
public void DoesTriggerOnDifferentStrings()
{
var hint = new StringOperatorEqualsHint();
Expression<Func<bool>> x = () => new string('x', 1) == "X"; // prevent inlining the constant
var p = new ExpressionParser(x.Body);
string description;
Assert.IsTrue(hint.TryGetHint(p, x.Body, out description));
Assert.IsNotNull(description);
}
public void HintPicksUpDiff()
{
var hint = new StringEqualsHint();
Expression<Func<bool>> x = () => "x".Equals("X");
var p = new ExpressionParser(x.Body);
string description;
Assert.IsTrue(hint.TryGetHint(p, x.Body, out description));
Assert.IsNotNull(description);
}
public void HintObeysComparer()
{
var hint = new StringEqualsHint();
Expression<Func<bool>> x = () => "x".Equals("X", StringComparison.OrdinalIgnoreCase);
var p = new ExpressionParser(x.Body);
string description;
Assert.IsFalse(hint.TryGetHint(p, x.Body, out description));
Assert.IsNull(description);
}
public void ShouldNotTriggerOnSequencesComparedWithEquals()
{
var hint = new SequenceEqualHint();
Expression<Func<bool>> exp = () => new List<int> {1}.Equals(new[] {2});
var p = new ExpressionParser(exp.Body);
string description;
Assert.IsFalse(hint.TryGetHint(p, exp.Body, out description));
Assert.IsNull(description);
}
protected override bool TryGetHint(ExpressionParser parser, object left, object right, out string hint)
{
if (Equals(left, right))
{
hint = ", but would have been True with Equals()";
return true;
}
hint = null;
return false;
}
public void ShouldBeTriggeredWithoutClosure_Right()
{
var hint = new DelegateShouldHaveBeenInvokedEqualsHint();
Func<int> f = () => 3;
Expression<Func<bool>> ex = () => Equals(3, f);
var p = new ExpressionParser(ex.Body);
string ignored;
Assert.IsTrue(hint.TryGetHint(p, ex.Body, out ignored));
Assert.IsNotNull(ignored);
}
public void ShouldPickUpTabVsSpace()
{
var hint = new StringOperatorEqualsHint();
Expression<Func<bool>> x = () => new string(' ', 1) == "\t"; // prevent inlining the constant
var p = new ExpressionParser(x.Body);
string description;
Assert.IsTrue(hint.TryGetHint(p, x.Body, out description));
Assert.IsNotNull(description);
Assert.IsTrue(description.Contains("tab"));
}
public void ShouldPickUpMismatchedNewlines()
{
var hint = new StringEqualsHint();
Expression<Func<bool>> x = () => new string('\n', 1).Equals("\r\n");
var p = new ExpressionParser(x.Body);
string description;
Assert.IsTrue(hint.TryGetHint(p, x.Body, out description));
Assert.IsNotNull(description);
Assert.IsTrue(description.Contains("carriage-return"));
}
public void ShouldPickUpControlCharacters()
{
var hint = new StringOperatorEqualsHint();
Expression<Func<bool>> x = () => new string('\0', 1) + "Hello" == "Hello"; // prevent inlining the constant
var p = new ExpressionParser(x.Body);
string description;
Assert.IsTrue(hint.TryGetHint(p, x.Body, out description));
Assert.IsNotNull(description);
Assert.IsTrue(description.Contains("control"));
}
public bool TryGetHint(ExpressionParser parser, Expression expression, out string hint)
{
foreach (var hinter in _hints)
{
if (hinter.TryGetHint(parser, expression, out hint))
{
return true;
}
}
hint = null;
return false;
}
public void ShouldPickUpTabVsSpace()
{
var hint = new StringEqualsHint();
Expression<Func<bool>> x = () => " ".Equals("\t");
var p = new ExpressionParser(x.Body);
string description;
Assert.IsTrue(hint.TryGetHint(p, x.Body, out description));
Assert.IsNotNull(description);
Assert.IsTrue(description.Contains("tab"));
}
public void ShouldPickUpDecomposedCharacters()
{
var hint = new StringEqualsHint();
Expression<Func<bool>> x = () => ConstantStrings.AcuteEComposed.Equals(ConstantStrings.AcuteEDecomposed);
var p = new ExpressionParser(x.Body);
string description;
Assert.IsTrue(hint.TryGetHint(p, x.Body, out description));
Assert.IsNotNull(description);
Assert.IsTrue(description.Contains("decomposed"));
}
public void ShouldTriggerOnSequenceEqualEnumerables()
{
var hint = new EnumerableOperatorEqualsHint();
var x = new[] {3};
var y = new[] {3};
Expression<Func<bool>> assertion = () => x == y;
var p = new ExpressionParser(assertion.Body);
string message;
Assert.IsTrue(hint.TryGetHint(p, assertion.Body, out message));
Assert.IsNotNull(message);
}
protected override bool TryGetHint(ExpressionParser parser, object left, object right, out string hint)
{
if (left is IEnumerable && right is IEnumerable)
{
if (((IEnumerable) left).Cast<object>().SequenceEqual(((IEnumerable) right).Cast<object>()))
{
hint = ", but would have been True with .SequenceEqual()";
return true;
}
}
hint = null;
return false;
}
public void ShouldTriggerForDifferentEnumerables()
{
var hint = new EnumerableOperatorEqualsHint();
object x = new[] {3};
object y = new List<int> {3};
Expression<Func<bool>> assertion = () => x == y;
var p = new ExpressionParser(assertion.Body);
string message;
Assert.IsTrue(hint.TryGetHint(p, assertion.Body, out message));
Assert.IsNotNull(message);
}
public void ShouldntTriggerOnEqualsMethod()
{
var hint = new EnumerableOperatorEqualsHint();
var x = new[] {3};
var y = new[] {3};
Expression<Func<bool>> assertion = () => x.Equals(y);
var p = new ExpressionParser(assertion.Body);
string message;
Assert.IsFalse(hint.TryGetHint(p, assertion.Body, out message));
Assert.IsNull(message);
}
public void ShouldBeTriggeredWithClosure_Left()
{
var hint = new DelegateShouldHaveBeenInvokedEqualsHint();
int n = 3;
Func<int> f = () => n; // now this func requires a closure
Expression<Func<bool>> ex = () => Equals(f, 3);
var p = new ExpressionParser(ex.Body);
string ignored;
Assert.IsTrue(hint.TryGetHint(p, ex.Body, out ignored));
Assert.IsNotNull(ignored);
}
public void ShouldNotBeTriggeredIfBothAreDelegates()
{
var hint = new DelegateShouldHaveBeenInvokedEqualsHint();
Func<int> f = () => 3;
Expression<Func<bool>> ex = () => Equals(f, f);
var p = new ExpressionParser(ex.Body);
string ignored;
Assert.IsTrue(hint.TryGetHint(p, ex.Body, out ignored));
Assert.IsTrue(ignored.Contains("suspicious"));
}
public void TestFloatFloatComparison()
{
float d = 0.1f;
float f = d*100;
f /= 100;
var floatHint = new FloatEqualityHint();
Expression<Func<bool>> exp = () => d == f;
var p = new ExpressionParser(exp.Body);
string description;
Assert.IsTrue(floatHint.TryGetHint(p, exp.Body, out description));
Assert.IsNotNull(description);
}
public void ParseMemberAccess()
{
DateTime d = new DateTime(2010, 12, 25);
Expression<Func<int>> f = () => d.Day;
var p = new ExpressionParser(f.Body);
MemberAccessNode node = (MemberAccessNode) p.Parse();
MemberAccessNode expected = new MemberAccessNode
{
Container = new ConstantNode {Text = "d", Value = d.ToString()},
MemberName = "Day",
MemberValue = "25"
};
Assert.AreEqual(expected, node);
}
public void ParseMethodAccess()
{
string s = "hello";
Expression<Func<string>> f = () => s.Substring(1);
var p = new ExpressionParser(f.Body);
var node = p.Parse();
var expected = new MethodCallNode
{
Container = new ConstantNode {Text = "s", Value = @"""hello"""},
MemberName = "Substring",
MemberValue = @"""ello""",
Parameters = new List<Node>() {new ConstantNode {Text = "1"}}
};
Assert.AreEqual(expected, node);
}
internal static string FormatObject(object value)
{
if (value == null)
{
return("null");
}
if (value is string)
{
return("\"" + value + "\"");
}
if (value is char)
{
return("'" + value + "'");
}
var exception = value as Exception;
if (exception != null)
{
return("{" + exception.GetType().Name + "}");
}
var type = value.GetType();
if (type.GetTypeInfo().IsGenericType&& type.GetGenericTypeDefinition() == typeof(KeyValuePair <,>))
{
var k = type.GetRuntimeProperty("Key").GetValue(value, null);
var v = type.GetRuntimeProperty("Value").GetValue(value, null);
return(String.Format("{{{0}:{1}}}", FormatObject(k), FormatObject(v)));
}
if (type.GetTypeInfo().ImplementedInterfaces
.Where(i => i.IsConstructedGenericType)
.Any(i => i.GetGenericTypeDefinition() == typeof(IGrouping <,>)))
{
var k = type.GetRuntimeProperty("Key").GetValue(value, null);
return(String.Format("{{{0}:{1}}}", FormatObject(k), FormatEnumerable(value)));
}
if (value is Type)
{
return("typeof(" + ExpressionParser.NameOfType((Type)value) + ")");
}
if (value is Delegate)
{
var del = (Delegate)value;
return(String.Format("delegate {0}, type: {2} ({1})", ExpressionParser.NameOfType(del.GetType()), String.Join(", ", del.GetMethodInfo().GetParameters().Select(x => ExpressionParser.NameOfType(x.ParameterType))), ExpressionParser.NameOfType(del.GetMethodInfo().ReturnType)));
}
if (value is IEnumerable)
{
return(FormatEnumerable(value));
}
return(value.ToString());
}
internal static string FormatObject(object value)
{
if (value == null)
{
return("null");
}
if (value is string)
{
return("\"" + value + "\"");
}
if (value is char)
{
return("'" + value + "'");
}
var exception = value as Exception;
if (exception != null)
{
return("{" + exception.GetType().Name + "}");
}
var type = value.GetType();
#if NETCOREAPP1_1
var isGenericType = new Func <Type, bool>(t => t.GetTypeInfo().IsGenericType);
#else
var isGenericType = new Func <Type, bool>(t => t.IsGenericType);
#endif
if (isGenericType(type) && type.GetGenericTypeDefinition() == typeof(KeyValuePair <,>))
{
var k = type.GetProperty("Key").GetValue(value, null);
var v = type.GetProperty("Value").GetValue(value, null);
return(String.Format("{{{0}:{1}}}", FormatObject(k), FormatObject(v)));
}
if (type.GetInterfaces()
.Where(isGenericType)
.Any(i => i.GetGenericTypeDefinition() == typeof(IGrouping <,>)))
{
var k = type.GetProperty("Key").GetValue(value, null);
return(String.Format("{{{0}:{1}}}", FormatObject(k), FormatEnumerable(value)));
}
if (value is Type)
{
return("typeof(" + ExpressionParser.NameOfType((Type)value) + ")");
}
if (value is Delegate)
{
var del = (Delegate)value;
#if NETCOREAPP1_1
var method = RuntimeReflectionExtensions.GetMethodInfo(del);
#else
var method = del.Method;
#endif
return(String.Format("delegate {0}, type: {2} ({1})", ExpressionParser.NameOfType(del.GetType()), String.Join(", ", method.GetParameters().Select(x => ExpressionParser.NameOfType(x.ParameterType))), ExpressionParser.NameOfType(method.ReturnType)));
}
if (value is IEnumerable)
{
return(FormatEnumerable(value));
}
return(value.ToString());
}
