uses-library com.android.nfc_extras breaks AndroidTest for api 26 and above when testing on a real device

Question

I've suddenly figured out that this declaration:

    <uses-library
        android:name="com.android.nfc_extras"
        android:required="false"/>

inside <application> scope of my AndroidManifest.xml makes instrumentation tests to fail:

java.lang.NoSuchMethodError: No static method allOf(Lorg/hamcrest/Matcher;Lorg/hamcrest/Matcher;)Lorg/hamcrest/Matcher; in class Lorg/hamcrest/core/AllOf; or its super classes (declaration of 'org.hamcrest.core.AllOf' appears in /system/framework/com.android.nfc_extras.jar)
at org.hamcrest.Matchers.allOf(Matchers.java:33)
at android.support.test.espresso.Espresso.<clinit>(Espresso.java:187)
at android.support.test.espresso.Espresso.onView(Espresso.java:75)
at com.example.abusik.espressotest.InstrumentedTest.changeText_sameActivity(InstrumentedTest.kt:34)
at java.lang.reflect.Method.invoke(Native Method)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)

What I came up with for now:

• Created a demo repository for you to be able to reproduce the problem quickly;
• Only a real devices with API >= 26 are affected (e.g. Samsung SM-G935F, Huawei P20 lite);
• Test passes on emulators with any API I have tried;
• Test passes on real devices with API < 26;
• Looks like missing class (and all his static methods) are included into AndroidTest apk, but at runtime Android tries to get this class from com.android.nfc_extras.jar???;
• This behaviour may depend on NFC-feature of your phone;
• It doesn't looks like MultiDex or obfuscation problem for me - the demo repository is not obfuscated and single-dex.

---

I would like to know if anybody faced this problem, why is this happening and how can I keep my AndroidTests working and still use this library?

---

My InstrumentedTest.kt file:

package com.example.abusik.espressotest

import android.support.test.espresso.Espresso.onView
import android.support.test.espresso.action.ViewActions.*
import android.support.test.espresso.assertion.ViewAssertions.matches
import android.support.test.espresso.matcher.ViewMatchers.withId
import android.support.test.espresso.matcher.ViewMatchers.withText
import android.support.test.filters.LargeTest
import android.support.test.rule.ActivityTestRule
import android.support.test.runner.AndroidJUnit4
import org.junit.Before
import org.junit.Rule
import org.junit.Test
import org.junit.runner.RunWith

@RunWith(AndroidJUnit4::class)
@LargeTest
class InstrumentedTest {

    private lateinit var stringToBetyped: String

    @get:Rule
    var activityRule: ActivityTestRule<MainActivity> = ActivityTestRule(MainActivity::class.java)

    @Before
    fun initValidString() {
        // Specify a valid string.
        stringToBetyped = "Espresso"
    }

    @Test
    fun changeText_sameActivity() {
        // Type text and then press the button.
        onView(withId(R.id.et)) //EXCEPTION THROWN HERE
            .perform(typeText(stringToBetyped), closeSoftKeyboard())
        onView(withId(R.id.btn)).perform(click())

        // Check that the text was changed.
        onView(withId(R.id.et))
            .check(matches(withText(stringToBetyped)))
    }
}

---

Test log:

Testing started at 0:09 ...

12/17 00:09:32: Launching InstrumentedTest
$ adb push /Users/a.busik/EspressoTest/app/build/outputs/apk/debug/app-debug.apk /data/local/tmp/com.example.abusik.espressotest
$ adb shell pm install -t -r "/data/local/tmp/com.example.abusik.espressotest"
Success
APK installed in 3 s 235 ms
$ adb push /Users/a.busik/EspressoTest/app/build/outputs/apk/androidTest/debug/app-debug-androidTest.apk /data/local/tmp/com.example.abusik.espressotest.test
$ adb shell pm install -t -r "/data/local/tmp/com.example.abusik.espressotest.test"
Success
APK installed in 2 s 684 ms
Running tests

$ adb shell am instrument -w -r   -e debug false -e class 'com.example.abusik.espressotest.InstrumentedTest' com.example.abusik.espressotest.test/android.support.test.runner.AndroidJUnitRunner
Client not ready yet..
Started running tests

java.lang.NoSuchMethodError: No static method allOf(Lorg/hamcrest/Matcher;Lorg/hamcrest/Matcher;)Lorg/hamcrest/Matcher; in class Lorg/hamcrest/core/AllOf; or its super classes (declaration of 'org.hamcrest.core.AllOf' appears in /system/framework/com.android.nfc_extras.jar)
at org.hamcrest.Matchers.allOf(Matchers.java:33)
at android.support.test.espresso.Espresso.<clinit>(Espresso.java:187)
at android.support.test.espresso.Espresso.onView(Espresso.java:75)
at com.example.abusik.espressotest.InstrumentedTest.changeText_sameActivity(InstrumentedTest.kt:34)
at java.lang.reflect.Method.invoke(Native Method)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at android.support.test.internal.runner.junit4.statement.RunBefores.evaluate(RunBefores.java:80)
at android.support.test.rule.ActivityTestRule$ActivityStatement.evaluate(ActivityTestRule.java:527)
at org.junit.rules.RunRules.evaluate(RunRules.java:20)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:68)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.-wrap0(Unknown Source:0)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at android.support.test.runner.AndroidJUnit4.run(AndroidJUnit4.java:101)
at org.junit.runners.Suite.runChild(Suite.java:128)
at org.junit.runners.Suite.runChild(Suite.java:126)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.-wrap0(Unknown Source:0)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at org.junit.runner.JUnitCore.run(JUnitCore.java:115)
at android.support.test.internal.runner.TestExecutor.execute(TestExecutor.java:56)
at android.support.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:384)
at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:2106)

Tests ran to completion.

---

I was able to find an nfc_extras.jar and it doesn't seem to contain any reference for org.hamcrest.*

Answer 1

unable to reproduce on a physical MotoX4 running Android 8.0.0.

a) com.android.nfc_extras.jar might have another version of org.hamcrest.Matcher than the test application - which could theoretically be excluded, when loading it from the libs directory. that the emulator does not care might come from, that there neither is BT nor NFC available.

the main/Manifest.xml also lacks the NFC permission; adding it removes the complaint:

<uses-permission android:name="android.permission.NFC" />

b) one could even get rid of the nfc_extras.jar altogether with an androidTest/Manifest.xml:

<?xml version="1.0" encoding="utf-8"?>
<manifest
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="com.example.abusik.espressotest">
    <application>
        <uses-library
            android:name="com.android.nfc_extras"
            android:required="false"
            tools:node="remove"/>
    </application>
</manifest>