Add some tests (mainly imported from EA). Also change type from String to SessionId, RoomId, etc.

libraries/core/src/test/kotlin/io/element/android/libraries/core/cache/CircularCacheTest.kt

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2023 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.element.android.libraries.core.cache
+
+import com.google.common.truth.Truth.assertThat
+import org.junit.Test
+
+class CircularCacheTest {
+    @Test
+    fun `when putting more than cache size then cache is limited to cache size`() {
+        val (cache, internalData) = createIntCache(cacheSize = 3)
+
+        cache.putInOrder(1, 1, 1, 1, 1, 1)
+
+        assertThat(internalData).isEqualTo(arrayOf(1, 1, 1))
+    }
+
+    @Test
+    fun `when putting more than cache then acts as FIFO`() {
+        val (cache, internalData) = createIntCache(cacheSize = 3)
+
+        cache.putInOrder(1, 2, 3, 4)
+
+        assertThat(internalData).isEqualTo(arrayOf(4, 2, 3))
+    }
+
+    @Test
+    fun `given empty cache when checking if contains key then is false`() {
+        val (cache, _) = createIntCache(cacheSize = 3)
+
+        val result = cache.contains(1)
+
+        assertThat(result).isFalse()
+    }
+
+    @Test
+    fun `given cached key when checking if contains key then is true`() {
+        val (cache, _) = createIntCache(cacheSize = 3)
+
+        cache.put(1)
+        val result = cache.contains(1)
+
+        assertThat(result).isTrue()
+    }
+
+    private fun createIntCache(cacheSize: Int): Pair<CircularCache<Int>, Array<Int?>> {
+        var internalData: Array<Int?>? = null
+        val factory: (Int) -> Array<Int?> = {
+            Array<Int?>(it) { null }.also { array -> internalData = array }
+        }
+        return CircularCache(cacheSize, factory) to internalData!!
+    }
+
+    private fun CircularCache<Int>.putInOrder(vararg values: Int) {
+        values.forEach { put(it) }
+    }
+}