chore: adds a unit test for json schema ref annotations parsing

Signed-off-by: Vincent Biret <[email protected]>

Author: baywet

test/Microsoft.OpenApi.Readers.Tests/V31Tests/OpenApiSchemaReferenceDeserializerTests.cs

@@ -0,0 +1,60 @@
+using System.Collections.Generic;
+using System.Text.Json.Nodes;
+using Microsoft.OpenApi.Reader;
+using Microsoft.OpenApi.Reader.V31;
+using Xunit;
+
+namespace Microsoft.OpenApi.Readers.Tests.V31Tests;
+
+public class OpenApiSchemaReferenceDeserializerTests
+{
+    [Fact]
+    public void ShouldDeserializeSchemaReferenceAnnotations()
+    {
+        var json =
+        """
+        {
+            "$ref": "#/components/schemas/MySchema",
+            "description": "This is a schema reference",
+            "default": "foo",
+            "readOnly": true,
+            "writeOnly": true,
+            "deprecated": true,
+            "title": "This is a schema reference",
+            "examples": ["example reference value"]
+        }
+        """;
+
+        var hostDocument = new OpenApiDocument();
+        hostDocument.AddComponent("MySchema", new OpenApiSchema
+        {
+            Title = "This is a schema",
+            Description = "This is a schema description",
+            Default = "bar",
+            Type = JsonSchemaType.String,
+            ReadOnly = false,
+            WriteOnly = false,
+            Deprecated = false,
+            Examples = new List<JsonNode> { "example value" },
+        });
+        var jsonNode = JsonNode.Parse(json);
+        var parseNode = ParseNode.Create(new ParsingContext(new()), jsonNode);
+
+        var result = OpenApiV31Deserializer.LoadSchema(parseNode, hostDocument);
+
+        Assert.NotNull(result);
+        var resultReference = Assert.IsType<OpenApiSchemaReference>(result);
+
+        Assert.Equal("MySchema", resultReference.Reference.Id);
+        Assert.Equal("This is a schema reference", resultReference.Description);
+        Assert.Equal("foo", resultReference.Default?.ToString());
+        Assert.True(resultReference.ReadOnly);
+        Assert.True(resultReference.WriteOnly);
+        Assert.True(resultReference.Deprecated);
+        Assert.Equal("This is a schema reference", resultReference.Title);
+        Assert.NotNull(resultReference.Examples);
+        Assert.Single(resultReference.Examples);
+        Assert.Equal("example reference value", resultReference.Examples[0]?.ToString());
+        Assert.NotNull(resultReference.Target);
+    }
+}