test(payload): test EventPayload trimming

Author: lemnik

bugsnag-android-core/src/test/java/com/bugsnag/android/EventPayloadTrimTest.kt

@@ -0,0 +1,64 @@
+package com.bugsnag.android
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.Mock
+import org.mockito.junit.MockitoJUnitRunner
+
+private const val MAX_STRING_LENGTH = 256
+private const val BIG_STRING_LENGTH = MAX_STRING_LENGTH * 4
+
+@RunWith(MockitoJUnitRunner::class)
+class EventPayloadTrimTest {
+
+    @Mock
+    lateinit var client: Client
+
+    @Test
+    fun testTrimPayload() {
+        val event = BugsnagTestUtils.generateEvent()
+        event.addMetadata("trimming", "bigString", "*".repeat(BIG_STRING_LENGTH))
+
+        // remove any existing threads to keep this test simple
+        event.threads.clear()
+        repeat(times = 10) { threadIdx ->
+            event.addThread(threadIdx.toLong(), "test thread $threadIdx")
+        }
+
+        event.breadcrumbs.clear()
+        repeat(times = 10) { breadcrumbIdx ->
+            event.leaveBreadcrumb("breadcrumb $breadcrumbIdx")
+        }
+
+        val config = BugsnagTestUtils.generateImmutableConfig(
+            Configuration("abc123").apply {
+                maxBreadcrumbs = 2
+                maxReportedThreads = 2
+                maxStringValueLength = MAX_STRING_LENGTH
+            }
+        )
+
+        val notifier = Notifier(name = "Test Notifier", version = "9.9.9")
+        val payload = EventPayload(null, event, null, notifier, config)
+        val trimmed = requireNotNull(payload.trimToSize(BIG_STRING_LENGTH).event)
+
+        assertEquals(
+            "${"*".repeat(MAX_STRING_LENGTH)}***<${BIG_STRING_LENGTH - MAX_STRING_LENGTH}> CHARS TRUNCATED***",
+            trimmed.getMetadata("trimming")!!["bigString"]
+        )
+
+        val threads = trimmed.threads
+        assertEquals(3, threads.size)
+        assertEquals("test thread 0", threads[0].name)
+        assertEquals("test thread 1", threads[1].name)
+        assertEquals(
+            "[8 threads omitted as the maxReportedThreads limit (2) was exceeded]",
+            threads[2].name
+        )
+
+        val breadcrumbs = trimmed.breadcrumbs
+        assertEquals(1, breadcrumbs.size)
+        assertEquals("Removed, along with 9 older breadcrumbs, to reduce payload size", breadcrumbs[0].message)
+    }
+}