public void ConditionalAccess_Update()
{
var rec1 = Expression.Constant(1, typeof(int?));
var nrc1 = CSharpExpression.ConditionalReceiver(typeof(int));
var wnn1 = Expression.Constant(1);
var rec2 = Expression.Constant(1, typeof(int?));
var nrc2 = CSharpExpression.ConditionalReceiver(typeof(int));
var wnn2 = Expression.Constant(1);
var ca0 = CSharpExpression.ConditionalAccess(rec1, nrc1, wnn1);
var ca1 = ca0.Update(rec1, nrc1, wnn1);
Assert.AreSame(ca0, ca1);
var ca2 = ca0.Update(rec2, nrc1, wnn1);
Assert.AreSame(rec2, ca2.Receiver);
Assert.AreSame(nrc1, ca2.NonNullReceiver);
Assert.AreSame(wnn1, ca2.WhenNotNull);
var ca3 = ca0.Update(rec1, nrc2, wnn1);
Assert.AreSame(rec1, ca3.Receiver);
Assert.AreSame(nrc2, ca3.NonNullReceiver);
Assert.AreSame(wnn1, ca3.WhenNotNull);
var ca4 = ca0.Update(rec1, nrc1, wnn2);
Assert.AreSame(rec1, ca4.Receiver);
Assert.AreSame(nrc1, ca4.NonNullReceiver);
Assert.AreSame(wnn2, ca4.WhenNotNull);
}
public void ConditionalAccess_Compile_Member4()
{
var p = Expression.Parameter(typeof(string));
var n = CSharpExpression.ConditionalReceiver(typeof(string));
var e = CSharpExpression.ConditionalAccess(p, n, Expression.Property(n, "Length"));
var f = Expression.Lambda <Func <string, int?> >(e, p);
var c = f.Compile();
foreach (var s in new string[] { null, "bar" })
{
Assert.AreEqual(s?.Length, c(s));
}
}
public void ConditionalAccess_Compile_Member2()
{
var p = Expression.Parameter(typeof(DateTimeOffset?));
var n = CSharpExpression.ConditionalReceiver(typeof(DateTimeOffset));
var e = CSharpExpression.ConditionalAccess(p, n, Expression.Property(Expression.Property(n, "Offset"), "Hours"));
var f = Expression.Lambda <Func <DateTimeOffset?, int?> >(e, p);
var c = f.Compile();
foreach (var d in new DateTimeOffset?[] { null, DateTimeOffset.Now })
{
Assert.AreEqual(d?.Offset.Hours, c(d));
}
}
public void ConditionalAccess_Compile_Potpourri2()
{
var p = Expression.Parameter(typeof(string));
var n = CSharpExpression.ConditionalReceiver(typeof(string));
var e = CSharpExpression.ConditionalAccess(p, n, CSharpExpression.ConditionalAccess(Expression.Call(Expression.Call(n, typeof(string).GetMethod("ToUpper", new Type[0])), typeof(string).GetMethod("ToLower", new Type[0])), n, Expression.Property(n, "Length")));
var f = Expression.Lambda <Func <string, int?> >(e, p);
var c = f.Compile();
foreach (var s in new string[] { null, "bar" })
{
Assert.AreEqual(s?.ToUpper().ToLower()?.Length, c(s));
}
}
public void ConditionalAccess_Compile_Potpourri1()
{
var p = Expression.Parameter(typeof(DateTimeOffset?));
var n = CSharpExpression.ConditionalReceiver(typeof(DateTimeOffset));
var m = CSharpExpression.ConditionalReceiver(typeof(string));
var e = CSharpExpression.ConditionalAccess(p, n, CSharpExpression.ConditionalAccess(Expression.Call(Expression.Property(n, "Offset"), typeof(TimeSpan).GetMethod("ToString", new Type[0])), m, Expression.Property(m, "Length")));
var f = Expression.Lambda <Func <DateTimeOffset?, int?> >(e, p);
var c = f.Compile();
foreach (var d in new DateTimeOffset?[] { null, DateTimeOffset.Now })
{
Assert.AreEqual(d?.Offset.ToString()?.Length, c(d));
}
}
public void ConditionalAccess_Compile_Invoke1()
{
var p = Expression.Parameter(typeof(Action));
var n = CSharpExpression.ConditionalReceiver(typeof(Action));
var e = CSharpExpression.ConditionalAccess(p, n, Expression.Invoke(n));
var f = Expression.Lambda <Action <Action> >(e, p);
var c = f.Compile();
c(null); // doesn't throw
var called = false;
c(() => { called = true; });
Assert.IsTrue(called);
}
public void ConditionalAccess_ArgumentChecking()
{
var rec = Expression.Constant(1, typeof(int?));
var nrc = CSharpExpression.ConditionalReceiver(typeof(int));
var wnn = Expression.Constant(1);
// null
AssertEx.Throws <ArgumentNullException>(() => CSharpExpression.ConditionalAccess(default(Expression), nrc, wnn));
AssertEx.Throws <ArgumentNullException>(() => CSharpExpression.ConditionalAccess(rec, default(ConditionalReceiver), wnn));
AssertEx.Throws <ArgumentNullException>(() => CSharpExpression.ConditionalAccess(rec, nrc, default(Expression)));
// invalid receiver type
AssertEx.Throws <ArgumentException>(() => CSharpExpression.ConditionalAccess(Expression.Empty(), nrc, wnn));
AssertEx.Throws <ArgumentException>(() => CSharpExpression.ConditionalAccess(Expression.Default(typeof(int)), nrc, wnn));
AssertEx.Throws <ArgumentException>(() => CSharpExpression.ConditionalAccess(Expression.Default(typeof(int).MakeByRefType()), nrc, wnn));
// type mismatch receiver
AssertEx.Throws <ArgumentException>(() => CSharpExpression.ConditionalAccess(Expression.Default(typeof(long?)), nrc, wnn));
AssertEx.Throws <ArgumentException>(() => CSharpExpression.ConditionalAccess(Expression.Default(typeof(string)), nrc, wnn));
}