Fix Options Source Gen with Length attributes applied on properties of Interface type

src/libraries/Microsoft.Extensions.Options/gen/ParserUtilities.cs

@@ -80,14 +80,26 @@ internal static bool TypeHasProperty(ITypeSymbol typeSymbol, string propertyName
 
                 if (type.GetMembers(propertyName).OfType<IPropertySymbol>().Any(property =>
                                                                                 property.Type.SpecialType == returnType && property.DeclaredAccessibility == Accessibility.Public &&
-                                                                                !property.IsStatic && property.GetMethod != null && property.Parameters.IsEmpty))
+                                                                                property.Kind == SymbolKind.Property && !property.IsStatic && property.GetMethod != null && property.Parameters.IsEmpty))
                 {
                     return true;
                 }
 
                 type = type.BaseType;
             } while (type is not null && type.SpecialType != SpecialType.System_Object);
 
+            // When we have an interface type, we need to check all the interfaces that it extends.
+            // Like IList<T> extends ICollection<T> where the property we're looking for is defined.
+            foreach (var interfaceType in typeSymbol.AllInterfaces)
+            {
+                if (interfaceType.GetMembers(propertyName).OfType<IPropertySymbol>().Any(property =>
+                                                                                property.Type.SpecialType == returnType && property.Kind == SymbolKind.Property &&
+                                                                                !property.IsStatic && property.GetMethod != null && property.Parameters.IsEmpty))
+                {
+                    return true;
+                }
+            }
+
             return false;
         }
 

src/libraries/Microsoft.Extensions.Options/tests/SourceGeneration.Unit.Tests/Main.cs

@@ -1813,4 +1813,44 @@ public sealed partial class OptionsUsingGeneratedAttributesValidator : IValidate
         Assert.True(emitResult.Success);
         // Console.WriteLine(emittedSource);
     }
+
+    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsNotBrowser))]
+    public async Task UsingInterfaceAsPropertyTypeForLengthAttributesTests()
+    {
+        var (diagnostics, generatedSources) = await RunGenerator(@"""
+            using System.Collections.Generic;
+
+            public class MyOptions
+            {
+                [Length(10, 20)]
+                public IList<string> P1 { get; set; }
+
+                [MinLength(4)]
+                public IList<string> P2 { get; set; }
+
+                [MaxLength(5)]
+                public IList<string> P3 { get; set; }
+
+                [Length(10, 20)]
+                public ICollection<string> P4 { get; set; }
+
+                [MinLength(4)]
+                public ICollection<string> P5 { get; set; }
+
+                [MaxLength(5)]
+                public ICollection<string> P6 { get; set; }
+            }
+
+            [OptionsValidator]
+            public partial class MyOptionsValidator : IValidateOptions<MyOptions>
+            {
+            }
+        """);
+
+        Assert.Empty(diagnostics);
+        Assert.Single(generatedSources);
+
+        // string generatedSource = File.ReadAllText(@"Baselines/DataAnnotationAttributesWithParams.g.cs");
+        // Assert.Equal(generatedSource.Replace("\r\n", "\n"), generatedSources[0].SourceText.ToString().Replace("\r\n", "\n"));
+    }
 }

src/libraries/Microsoft.Extensions.Options/tests/SourceGeneration.Unit.Tests/OptionsRuntimeTests.cs

@@ -287,6 +287,12 @@ public void TestCustomGeneratedAttributes()
                 P23 = new List<string>() { "1", "2", "3", "4" },
                 P24 = new FakeCount(4),
                 P25 = new FakeCountChild(4),
+                P27 = new List<string> { "1", "2" },
+                P28 = new HashSet<string> { "1", "2" },
+                P29 = new List<string> { "1", "2", "3" },
+                P30 = new HashSet<string> { "1", "2", "3" },
+                P31 = new List<int> { 1, 2, 3, 4 },
+                P32 = new HashSet<int> { 1, 2, 3, 4 },
 #endif // NET8_0_OR_GREATER
                 P1 = 2,
                 P2 = "12345",
@@ -325,6 +331,12 @@ public void TestCustomGeneratedAttributes()
                 P23 = new List<string>() { "1", "2", "3", "4", "5" },
                 P24 = new FakeCount(5),
                 P25 = new FakeCountChild(5),
+                P27 = new List<string> { "1" },
+                P28 = new HashSet<string> { "1" },
+                P29 = new List<string> { "1", "2" },
+                P30 = new HashSet<string> { "1", "2" },
+                P31 = new List<int> { 1, 2, 3, 4, 5 },
+                P32 = new HashSet<int> { 1, 2, 3, 4, 5 },
 #endif // NET8_0_OR_GREATER
                 P1 = 4,
                 P2 = "1234",
@@ -362,6 +374,12 @@ public void TestCustomGeneratedAttributes()
                 "P23: The field OptionsUsingGeneratedAttributes.P23 must be a string or array type with a maximum length of '4'.",
                 "P24: The field OptionsUsingGeneratedAttributes.P24 must be a string or array type with a maximum length of '4'.",
                 "P25: The field OptionsUsingGeneratedAttributes.P25 must be a string or array type with a maximum length of '4'.",
+                "P27: The field OptionsUsingGeneratedAttributes.P27 must be a string or collection type with a minimum length of '2' and maximum length of '10'.",
+                "P28: The field OptionsUsingGeneratedAttributes.P28 must be a string or collection type with a minimum length of '2' and maximum length of '10'.",
+                "P29: The field OptionsUsingGeneratedAttributes.P29 must be a string or array type with a minimum length of '3'.",
+                "P30: The field OptionsUsingGeneratedAttributes.P30 must be a string or array type with a minimum length of '3'.",
+                "P31: The field OptionsUsingGeneratedAttributes.P31 must be a string or array type with a maximum length of '4'.",
+                "P32: The field OptionsUsingGeneratedAttributes.P32 must be a string or array type with a maximum length of '4'.",
 #endif // NET8_0_OR_GREATER
                 "P1: The field OptionsUsingGeneratedAttributes.P1 must be between 1 and 3.",
                 "P2: The field OptionsUsingGeneratedAttributes.P2 must be a string or array type with a minimum length of '5'.",
@@ -412,6 +430,9 @@ public class OptionsUsingGeneratedAttributes
         [LengthAttribute(2, 10)]
         public int[] P17 { get; set; }
 
+        // Although MinLength and MaxLength attributes defined in NETFX but the implementation there has a bug which can produce exception like the following when using types like List<string>:
+        // System.InvalidCastException : Unable to cast object of type 'System.Collections.Generic.List`1[System.String]' to type 'System.Array'.
+
         [MinLengthAttribute(3)]
         public List<string> P18 { get; set; }
 
@@ -429,6 +450,24 @@ public class OptionsUsingGeneratedAttributes
 
         [MaxLengthAttribute(4)]
         public FakeCountChild P25 { get; set; }
+
+        [LengthAttribute(2, 10)]
+        public IList<string> P27 { get; set; }
+
+        [LengthAttribute(2, 10)]
+        public ICollection<string> P28 { get; set; }
+
+        [MinLengthAttribute(3)]
+        public IList<string> P29 { get; set; }
+
+        [MinLengthAttribute(3)]
+        public ICollection<string> P30 { get; set; }
+
+        [MaxLengthAttribute(4)]
+        public IList<int> P31 { get; set; }
+
+        [MaxLengthAttribute(4)]
+        public ICollection<int> P32 { get; set; }
 #endif // NET8_0_OR_GREATER
 
         [RangeAttribute(1, 3)]