1 files changed, 176 insertions, 0 deletions
diff --git a/formats/json-tests/commonTest/src/kotlinx/serialization/json/JsonTestBase.kt b/formats/json-tests/commonTest/src/kotlinx/serialization/json/JsonTestBase.kt
new file mode 100644
index 00000000..6f3b132e
--- /dev/null
+++ b/formats/json-tests/commonTest/src/kotlinx/serialization/json/JsonTestBase.kt
@@ -0,0 +1,176 @@
+/*
+ * Copyright 2017-2022 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package kotlinx.serialization.json
+
+import kotlinx.serialization.*
+import kotlinx.serialization.json.internal.*
+import kotlinx.serialization.json.okio.decodeFromBufferedSource
+import kotlinx.serialization.json.okio.encodeToBufferedSink
+import kotlinx.serialization.modules.EmptySerializersModule
+import kotlinx.serialization.modules.SerializersModule
+import kotlinx.serialization.test.*
+import kotlin.test.assertEquals
+import okio.*
+import kotlin.test.assertTrue
+
+
+enum class JsonTestingMode {
+    STREAMING,
+    TREE,
+    OKIO_STREAMS,
+    JAVA_STREAMS;
+
+    companion object {
+        fun value(i: Int) = values()[i]
+    }
+}
+
+abstract class JsonTestBase {
+    protected val default = Json { encodeDefaults = true }
+    protected val lenient = Json { isLenient = true; ignoreUnknownKeys = true; allowSpecialFloatingPointValues = true }
+
+    internal inline fun <reified T : Any> Json.encodeToString(value: T, jsonTestingMode: JsonTestingMode): String {
+        val serializer = serializersModule.serializer<T>()
+        return encodeToString(serializer, value, jsonTestingMode)
+    }
+
+    internal fun <T> Json.encodeToString(
+        serializer: SerializationStrategy<T>,
+        value: T,
+        jsonTestingMode: JsonTestingMode
+    ): String =
+        when (jsonTestingMode) {
+            JsonTestingMode.STREAMING -> {
+                encodeToString(serializer, value)
+            }
+            JsonTestingMode.JAVA_STREAMS -> {
+                encodeViaStream(serializer, value)
+            }
+            JsonTestingMode.TREE -> {
+                val tree = writeJson(this, value, serializer)
+                encodeToString(tree)
+            }
+            JsonTestingMode.OKIO_STREAMS -> {
+                val buffer = Buffer()
+                encodeToBufferedSink(serializer, value, buffer)
+                buffer.readUtf8()
+            }
+        }
+
+    internal inline fun <reified T : Any> Json.decodeFromString(source: String, jsonTestingMode: JsonTestingMode): T {
+        val deserializer = serializersModule.serializer<T>()
+        return decodeFromString(deserializer, source, jsonTestingMode)
+    }
+
+    internal fun <T> Json.decodeFromString(
+        deserializer: DeserializationStrategy<T>,
+        source: String,
+        jsonTestingMode: JsonTestingMode
+    ): T =
+        when (jsonTestingMode) {
+            JsonTestingMode.STREAMING -> {
+                decodeFromString(deserializer, source)
+            }
+            JsonTestingMode.JAVA_STREAMS -> {
+                decodeViaStream(deserializer, source)
+            }
+            JsonTestingMode.TREE -> {
+                val tree = decodeStringToJsonTree(this, deserializer, source)
+                readJson(this, tree, deserializer)
+            }
+            JsonTestingMode.OKIO_STREAMS -> {
+                val buffer = Buffer()
+                buffer.writeUtf8(source)
+                decodeFromBufferedSource(deserializer, buffer)
+            }
+        }
+
+    protected open fun parametrizedTest(test: (JsonTestingMode) -> Unit) {
+        processResults(buildList {
+            add(runCatching { test(JsonTestingMode.STREAMING) })
+            add(runCatching { test(JsonTestingMode.TREE) })
+            add(runCatching { test(JsonTestingMode.OKIO_STREAMS) })
+
+            if (isJvm()) {
+                add(runCatching { test(JsonTestingMode.JAVA_STREAMS) })
+            }
+        })
+    }
+
+    private inner class SwitchableJson(
+        val json: Json,
+        val jsonTestingMode: JsonTestingMode,
+        override val serializersModule: SerializersModule = EmptySerializersModule()
+    ) : StringFormat {
+        override fun <T> encodeToString(serializer: SerializationStrategy<T>, value: T): String {
+            return json.encodeToString(serializer, value, jsonTestingMode)
+        }
+
+        override fun <T> decodeFromString(deserializer: DeserializationStrategy<T>, string: String): T {
+            return json.decodeFromString(deserializer, string, jsonTestingMode)
+        }
+    }
+
+    protected fun parametrizedTest(json: Json, test: StringFormat.() -> Unit) {
+        val streamingResult = runCatching { SwitchableJson(json, JsonTestingMode.STREAMING).test() }
+        val treeResult = runCatching { SwitchableJson(json, JsonTestingMode.TREE).test() }
+        val okioResult = runCatching { SwitchableJson(json, JsonTestingMode.OKIO_STREAMS).test() }
+        processResults(listOf(streamingResult, treeResult, okioResult))
+    }
+
+    protected fun processResults(results: List<Result<*>>) {
+        results.forEachIndexed { i, result ->
+            result.onFailure {
+                println("Failed test for ${JsonTestingMode.value(i)}")
+                throw it
+            }
+        }
+        for (i in results.indices) {
+            for (j in results.indices) {
+                if (i == j) continue
+                assertEquals(
+                    results[i].getOrNull()!!,
+                    results[j].getOrNull()!!,
+                    "Results differ for ${JsonTestingMode.value(i)} and ${JsonTestingMode.value(j)}"
+                )
+            }
+        }
+    }
+
+    /**
+     * Same as [assertStringFormAndRestored], but tests both json converters (streaming and tree)
+     * via [parametrizedTest]
+     */
+    internal fun <T> assertJsonFormAndRestored(
+        serializer: KSerializer<T>,
+        data: T,
+        expected: String,
+        json: Json = default
+    ) {
+        parametrizedTest { jsonTestingMode ->
+            val serialized = json.encodeToString(serializer, data, jsonTestingMode)
+            assertEquals(expected, serialized, "Failed with streaming = $jsonTestingMode")
+            val deserialized: T = json.decodeFromString(serializer, serialized, jsonTestingMode)
+            assertEquals(data, deserialized, "Failed with streaming = $jsonTestingMode")
+        }
+    }
+    /**
+     * Same as [assertStringFormAndRestored], but tests both json converters (streaming and tree)
+     * via [parametrizedTest]. Use custom checker for deserialized value.
+     */
+    internal fun <T> assertJsonFormAndRestoredCustom(
+        serializer: KSerializer<T>,
+        data: T,
+        expected: String,
+        check: (T, T) -> Boolean
+    ) {
+        parametrizedTest { jsonTestingMode ->
+            val serialized = Json.encodeToString(serializer, data, jsonTestingMode)
+            assertEquals(expected, serialized, "Failed with streaming = $jsonTestingMode")
+            val deserialized: T = Json.decodeFromString(serializer, serialized, jsonTestingMode)
+            assertTrue("Failed with streaming = $jsonTestingMode\n\tsource value =$data\n\tdeserialized value=$deserialized") { check(data, deserialized) }
+        }
+    }
+}