feat(client): make union deserialization more robust (#521)

feat(client): add enum validation method
chore(client): remove unnecessary json state from some query param classes
chore(internal): add json roundtripping tests
chore(internal): add invalid json deserialization tests

Author: stainless-app[bot]

finch-java-core/src/main/kotlin/com/tryfinch/api/core/BaseDeserializer.kt

@@ -7,11 +7,9 @@ import com.fasterxml.jackson.databind.BeanProperty
 import com.fasterxml.jackson.databind.DeserializationContext
 import com.fasterxml.jackson.databind.JavaType
 import com.fasterxml.jackson.databind.JsonDeserializer
-import com.fasterxml.jackson.databind.JsonMappingException
 import com.fasterxml.jackson.databind.JsonNode
 import com.fasterxml.jackson.databind.deser.ContextualDeserializer
 import com.fasterxml.jackson.databind.deser.std.StdDeserializer
-import com.tryfinch.api.errors.FinchInvalidDataException
 import kotlin.reflect.KClass
 
 abstract class BaseDeserializer<T : Any>(type: KClass<T>) :
@@ -30,38 +28,17 @@ abstract class BaseDeserializer<T : Any>(type: KClass<T>) :
 
     protected abstract fun ObjectCodec.deserialize(node: JsonNode): T
 
-    protected fun <T> ObjectCodec.deserialize(node: JsonNode, type: TypeReference<T>): T =
+    protected fun <T> ObjectCodec.tryDeserialize(node: JsonNode, type: TypeReference<T>): T? =
         try {
             readValue(treeAsTokens(node), type)
         } catch (e: Exception) {
-            throw FinchInvalidDataException("Error deserializing", e)
-        }
-
-    protected fun <T> ObjectCodec.tryDeserialize(
-        node: JsonNode,
-        type: TypeReference<T>,
-        validate: (T) -> Unit = {},
-    ): T? {
-        return try {
-            readValue(treeAsTokens(node), type).apply(validate)
-        } catch (e: JsonMappingException) {
-            null
-        } catch (e: RuntimeException) {
             null
         }
-    }
 
-    protected fun <T> ObjectCodec.tryDeserialize(
-        node: JsonNode,
-        type: JavaType,
-        validate: (T) -> Unit = {},
-    ): T? {
-        return try {
-            readValue<T>(treeAsTokens(node), type).apply(validate)
-        } catch (e: JsonMappingException) {
-            null
-        } catch (e: RuntimeException) {
+    protected fun <T> ObjectCodec.tryDeserialize(node: JsonNode, type: JavaType): T? =
+        try {
+            readValue(treeAsTokens(node), type)
+        } catch (e: Exception) {
             null
         }
-    }
 }

finch-java-core/src/main/kotlin/com/tryfinch/api/core/Utils.kt

@@ -26,6 +26,34 @@ internal fun <K : Comparable<K>, V> SortedMap<K, V>.toImmutable(): SortedMap<K,
     if (isEmpty()) Collections.emptySortedMap()
     else Collections.unmodifiableSortedMap(toSortedMap(comparator()))
 
+/**
+ * Returns all elements that yield the largest value for the given function, or an empty list if
+ * there are zero elements.
+ *
+ * This is similar to [Sequence.maxByOrNull] except it returns _all_ elements that yield the largest
+ * value; not just the first one.
+ */
+@JvmSynthetic
+internal fun <T, R : Comparable<R>> Sequence<T>.allMaxBy(selector: (T) -> R): List<T> {
+    var maxValue: R? = null
+    val maxElements = mutableListOf<T>()
+
+    val iterator = iterator()
+    while (iterator.hasNext()) {
+        val element = iterator.next()
+        val value = selector(element)
+        if (maxValue == null || value > maxValue) {
+            maxValue = value
+            maxElements.clear()
+            maxElements.add(element)
+        } else if (value == maxValue) {
+            maxElements.add(element)
+        }
+    }
+
+    return maxElements
+}
+
 /**
  * Returns whether [this] is equal to [other].
  *

finch-java-core/src/main/kotlin/com/tryfinch/api/models/AccessTokenCreateParams.kt

@@ -529,6 +529,27 @@ private constructor(
             validated = true
         }
 
+        fun isValid(): Boolean =
+            try {
+                validate()
+                true
+            } catch (e: FinchInvalidDataException) {
+                false
+            }
+
+        /**
+         * Returns a score indicating how many valid values are contained in this object
+         * recursively.
+         *
+         * Used for best match union deserialization.
+         */
+        @JvmSynthetic
+        internal fun validity(): Int =
+            (if (code.asKnown().isPresent) 1 else 0) +
+                (if (clientId.asKnown().isPresent) 1 else 0) +
+                (if (clientSecret.asKnown().isPresent) 1 else 0) +
+                (if (redirectUri.asKnown().isPresent) 1 else 0)
+
         override fun equals(other: Any?): Boolean {
             if (this === other) {
                 return true

finch-java-core/src/main/kotlin/com/tryfinch/api/models/AccountCreateResponse.kt

@@ -17,6 +17,7 @@ import com.tryfinch.api.core.toImmutable
 import com.tryfinch.api.errors.FinchInvalidDataException
 import java.util.Collections
 import java.util.Objects
+import kotlin.jvm.optionals.getOrNull
 
 class AccountCreateResponse
 private constructor(
@@ -391,14 +392,37 @@ private constructor(
 
         accessToken()
         accountId()
-        authenticationType()
+        authenticationType().validate()
         companyId()
         connectionId()
         products()
         providerId()
         validated = true
     }
 
+    fun isValid(): Boolean =
+        try {
+            validate()
+            true
+        } catch (e: FinchInvalidDataException) {
+            false
+        }
+
+    /**
+     * Returns a score indicating how many valid values are contained in this object recursively.
+     *
+     * Used for best match union deserialization.
+     */
+    @JvmSynthetic
+    internal fun validity(): Int =
+        (if (accessToken.asKnown().isPresent) 1 else 0) +
+            (if (accountId.asKnown().isPresent) 1 else 0) +
+            (authenticationType.asKnown().getOrNull()?.validity() ?: 0) +
+            (if (companyId.asKnown().isPresent) 1 else 0) +
+            (if (connectionId.asKnown().isPresent) 1 else 0) +
+            (products.asKnown().getOrNull()?.size ?: 0) +
+            (if (providerId.asKnown().isPresent) 1 else 0)
+
     class AuthenticationType
     @JsonCreator
     private constructor(private val value: JsonField<String>) : Enum {
@@ -500,6 +524,33 @@ private constructor(
         fun asString(): String =
             _value().asString().orElseThrow { FinchInvalidDataException("Value is not a String") }
 
+        private var validated: Boolean = false
+
+        fun validate(): AuthenticationType = apply {
+            if (validated) {
+                return@apply
+            }
+
+            known()
+            validated = true
+        }
+
+        fun isValid(): Boolean =
+            try {
+                validate()
+                true
+            } catch (e: FinchInvalidDataException) {
+                false
+            }
+
+        /**
+         * Returns a score indicating how many valid values are contained in this object
+         * recursively.
+         *
+         * Used for best match union deserialization.
+         */
+        @JvmSynthetic internal fun validity(): Int = if (value() == Value._UNKNOWN) 0 else 1
+
         override fun equals(other: Any?): Boolean {
             if (this === other) {
                 return true