Add test cases from #281

src/test/kotlin/com/fasterxml/jackson/module/kotlin/test/github/GitHub281.kt

@@ -0,0 +1,59 @@
+package com.fasterxml.jackson.module.kotlin.test.github
+
+import com.fasterxml.jackson.annotation.JsonIdentityInfo
+import com.fasterxml.jackson.annotation.JsonTypeInfo
+import com.fasterxml.jackson.annotation.ObjectIdGenerators
+import com.fasterxml.jackson.module.kotlin.jacksonObjectMapper
+import com.fasterxml.jackson.module.kotlin.readValue
+import com.fasterxml.jackson.module.kotlin.testPrettyWriter
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertSame
+
+class GitHub281 {
+    @JsonTypeInfo(use = JsonTypeInfo.Id.MINIMAL_CLASS, include = JsonTypeInfo.As.PROPERTY, property = "@type")
+    @JsonIdentityInfo(generator = ObjectIdGenerators.IntSequenceGenerator::class, property = "@id")
+    interface Entity
+
+    object NumberEntity : Entity
+
+    data class NumberValue(val value: Int) {
+        val entity = NumberEntity
+    }
+
+    private val json = """
+        [ {
+          "value" : 10,
+          "entity" : {
+            "@type" : ".GitHub281${'$'}NumberEntity",
+            "@id" : 1
+          }
+        }, {
+          "value" : 11,
+          "entity" : 1
+        } ]
+        """.trimIndent()
+
+    @Test
+    fun `test writing involving type, id and object`() {
+        val input = listOf(NumberValue(10), NumberValue(11))
+
+        val output = jacksonObjectMapper()
+            .testPrettyWriter()
+            .writeValueAsString(input)
+
+        assertEquals(json, output)
+    }
+
+    @Test
+    fun `test reading involving type, id and object`() {
+        val output = jacksonObjectMapper().readValue<List<NumberValue>>(json)
+
+        assertEquals(2, output.size)
+        val (a, b) = output
+        assertSame(NumberEntity::class.java, a.entity.javaClass)
+        assertSame(NumberEntity::class.java, b.entity.javaClass)
+        assertEquals(10, a.value)
+        assertEquals(11, b.value)
+    }
+}