Android tests build error: Multiple dex files define Landroid/support/test/BuildConfig

Question

I'm trying to add Espresso 2 to my project (which also has lots of other dependencies), but I'm hitting this error when trying to run tests:

UNEXPECTED TOP-LEVEL EXCEPTION:
com.android.dex.DexException: Multiple dex files define Landroid/support/test/BuildConfig;
    at com.android.dx.merge.DexMerger.readSortableTypes(DexMerger.java:596)
    at com.android.dx.merge.DexMerger.getSortedTypes(DexMerger.java:554)
    at com.android.dx.merge.DexMerger.mergeClassDefs(DexMerger.java:535)
    ...

The non-test build works fine.

Does anybody have any tips on the best way to debug this?

I've tried running ./gradlew -q :<my_project>:dependencies, but I can't see any obvious problems (though I don't know much about interpreting its output):

<snip>

androidTestCompile - Classpath for compiling the androidTest sources.
+--- com.squareup.spoon:spoon-client:1.1.2
+--- com.google.dexmaker:dexmaker-mockito:1.0
|    +--- com.google.dexmaker:dexmaker:1.0
|    \--- org.mockito:mockito-core:1.9.5
|         +--- org.hamcrest:hamcrest-core:1.1
|         \--- org.objenesis:objenesis:1.0
+--- com.google.dexmaker:dexmaker:1.0
+--- org.mockito:mockito-core:1.9.5 (*)
+--- com.jayway.android.robotium:robotium-solo:5.3.1
+--- com.android.support.test.espresso:espresso-core:2.0
|    +--- com.squareup:javawriter:2.1.1
|    +--- org.hamcrest:hamcrest-integration:1.1
|    |    \--- org.hamcrest:hamcrest-core:1.1
|    +--- org.hamcrest:hamcrest-library:1.1
|    |    \--- org.hamcrest:hamcrest-core:1.1
|    +--- javax.inject:javax.inject:1
|    +--- com.android.support.test.espresso:espresso-idling-resource:2.0
|    +--- com.android.support.test:testing-support-lib:0.1
|    |    \--- junit:junit-dep:4.10
|    |         \--- org.hamcrest:hamcrest-core:1.1
|    +--- com.google.code.findbugs:jsr305:2.0.1
|    +--- javax.annotation:javax.annotation-api:1.2
|    \--- org.hamcrest:hamcrest-core:1.1
\--- com.android.support.test:runner:0.2
     +--- junit:junit-dep:4.10 (*)
     +--- com.android.support.test:exposed-instrumentation-api-publish:0.2
     \--- com.android.support:support-annotations:22.0.0

<snip>

compile - Classpath for compiling the main sources.
+--- com.android.support:appcompat-v7:22.1.0
|    \--- com.android.support:support-v4:22.1.0
|         \--- com.android.support:support-annotations:22.1.0
+--- com.android.support:support-v4:22.1.0 (*)
+--- com.afollestad:material-dialogs:0.7.2.4
|    +--- com.android.support:support-v4:22.0.0 -> 22.1.0 (*)
|    +--- com.android.support:appcompat-v7:22.0.0 -> 22.1.0 (*)
|    +--- com.android.support:support-annotations:22.0.0 -> 22.1.0
|    \--- com.android.support:recyclerview-v7:22.0.0
|         +--- com.android.support:support-v4:22.0.0 -> 22.1.0 (*)
|         \--- com.android.support:support-annotations:22.0.0 -> 22.1.0
+--- com.google.android.gms:play-services-base:7.0.0
|    \--- com.android.support:support-v4:22.0.0 -> 22.1.0 (*)
+--- com.google.android.gms:play-services-gcm:7.0.0
|    \--- com.google.android.gms:play-services-base:7.0.0 (*)
+--- de.greenrobot:greendao:1.3.7
+--- de.greenrobot:eventbus:2.2.0
+--- com.squareup.wire:wire-runtime:1.4.0
|    \--- com.squareup.okio:okio:0.6.0 -> 1.0.1
+--- com.squareup.okio:okio:1.0.1
+--- com.squareup.okhttp:okhttp-urlconnection:2.0.0
|    \--- com.squareup.okhttp:okhttp:2.0.0
|         \--- com.squareup.okio:okio:1.0.0 -> 1.0.1
+--- com.squareup.retrofit:retrofit:1.6.0
|    \--- com.google.code.gson:gson:2.2.4
+--- com.squareup.retrofit:converter-wire:1.6.0
|    +--- com.squareup.retrofit:retrofit:1.6.0 (*)
|    \--- com.squareup.wire:wire-runtime:1.2.0 -> 1.4.0 (*)
+--- com.squareup.okhttp:okhttp:2.0.0 (*)
+--- com.squareup.picasso:picasso:2.4.0
+--- com.path:android-priority-jobqueue:1.1.2
|    \--- com.google.android:android:2.2.1
|         +--- commons-logging:commons-logging:1.1.1
|         +--- org.apache.httpcomponents:httpclient:4.0.1
|         |    +--- org.apache.httpcomponents:httpcore:4.0.1
|         |    +--- commons-logging:commons-logging:1.1.1
|         |    \--- commons-codec:commons-codec:1.3
|         +--- org.khronos:opengl-api:gl1.1-android-2.1_r1
|         +--- xerces:xmlParserAPIs:2.6.2
|         +--- xpp3:xpp3:1.1.4c
|         \--- org.json:json:20080701
+--- com.netflix.rxjava:rxjava-android:0.16.1
|    \--- com.netflix.rxjava:rxjava-core:0.16.1
+--- com.nineoldandroids:library:2.4.0
+--- it.sephiroth.android.library.horizontallistview:hlistview:1.2.2
|    \--- com.android.support:support-v4:19.1.+ -> 22.1.0 (*)
+--- com.joooonho:selectableroundedimageview:1.0.1
+--- com.crashlytics.sdk.android:crashlytics:2.0.1
|    +--- com.crashlytics.sdk.android:answers:1.0.1
|    |    \--- io.fabric.sdk.android:fabric:1.0.1
|    +--- io.fabric.sdk.android:fabric:1.0.1
|    \--- com.crashlytics.sdk.android:beta:1.0.1
|         \--- io.fabric.sdk.android:fabric:1.0.1
+--- com.mixpanel.android:mixpanel-android:4.5.3
\--- com.facebook.android:facebook-android-sdk:4.0.0
     +--- com.android.support:support-v4:[21,22) -> 22.1.0 (*)
     \--- com.parse.bolts:bolts-android:1.1.4

<snip>

I've also tried searching subfolders of my build/intermediates directory, but I couldn't see any smoking guns (though I'm not sure I was searching all the external dependency JARs in the right way).

Here is the dependency section of my build.gradle:

dependencies {
    compile 'com.android.support:appcompat-v7:22.1.0'
    compile 'com.android.support:support-v4:22.1.0'
    compile 'com.afollestad:material-dialogs:0.7.2.4'
    compile 'com.google.android.gms:play-services-base:7.0.0'
    compile 'com.google.android.gms:play-services-gcm:7.0.0'
    compile 'de.greenrobot:greendao:1.3.7'
    compile 'de.greenrobot:eventbus:2.2.0'
    compile 'com.squareup.wire:wire-runtime:1.4.0'
    compile 'com.squareup.okio:okio:1.0.1'
    compile 'com.squareup.okhttp:okhttp-urlconnection:2.0.0'
    compile 'com.squareup.retrofit:retrofit:1.6.0'
    compile 'com.squareup.retrofit:converter-wire:1.6.0'
    compile 'com.squareup.okhttp:okhttp:2.0.0'
    compile 'com.squareup.picasso:picasso:2.4.0'
    compile 'com.path:android-priority-jobqueue:1.1.2'
    compile 'com.netflix.rxjava:rxjava-android:0.16.1'
    compile 'com.nineoldandroids:library:2.4.0'
    compile 'it.sephiroth.android.library.horizontallistview:hlistview:1.2.2'
    compile 'com.joooonho:selectableroundedimageview:1.0.1'
    compile('com.crashlytics.sdk.android:crashlytics:2.0.1@aar') {
        transitive = true;
    }
    compile "com.mixpanel.android:mixpanel-android:4.5.3"
    compile "com.facebook.android:facebook-android-sdk:4.0.0"

    // For the Rollbar JAR, as it is not available in Maven central
    compile fileTree(dir: 'libs', include: '*.jar')

    androidTestCompile 'com.squareup.spoon:spoon-client:1.1.2'
    androidTestCompile 'com.google.dexmaker:dexmaker-mockito:1.0'
    androidTestCompile 'com.google.dexmaker:dexmaker:1.0'
    androidTestCompile 'org.mockito:mockito-core:1.9.5'
    androidTestCompile 'com.jayway.android.robotium:robotium-solo:5.3.1'
    androidTestCompile 'com.android.support.test.espresso:espresso-core:2.0'
    androidTestCompile 'com.android.support.test:runner:0.2'
}

Update: when I update from com.android.tools.build:gradle:1.0.0 to com.android.tools.build:gradle:1.1.1, I get this warning:

Warning:Conflict with dependency 'com.android.support:support-annotations'. Resolved versions for app (22.1.0) and test app (22.0.0) differ.

Answer 1

Update (9/07/2015):

You can continue to work with 22.2.1 if you use the following excludes:

androidTestCompile ('com.android.support.test.espresso:espresso-core:2.2') {
    exclude group: 'com.android.support', module: 'support-annotations'
}
androidTestCompile ('com.android.support.test:runner:0.3') {
    exclude group: 'com.android.support', module: 'support-annotations'
}
androidTestCompile ('com.android.support.test:rules:0.3') {
    exclude group: 'com.android.support', module: 'support-annotations'
}

If you depend on espresso-contrib, you need the exclude as well.

Update (8/03/2015):

With support library 22.2.1, the dependencies are broken again; please don't upgrade to 22.2.1 until a new runner is released.

Update (6/04/2015):

With the latest release of runner 0.3 and rules 0.3, this answer is no longer needed. You can simply use

androidTestCompile 'com.android.support.test:runner:0.3'
androidTestCompile 'com.android.support.test:rules:0.3'
androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2'

with latest support libraries. (22.2.0 as of this writing)

Update (5/30/2015):

compile 'com.android.support:appcompat-v7:22.2.0'
androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2'
// com.android.support.test:testing-support-lib:0.1 // <-- causes issue

Update (4/24/2015):

The problem is that com.android.support:support-v4:22.1.1 is clashing with com.android.support.test:runner:0.2 (as that depends on com.android.support:support-v4:22.0.0).

com.android.support.test.espresso:espresso-core:2.1 has a dependency on com.android.support.test:runner:0.2, so it also causes the same error.

So, this combination will work:

compile 'com.android.support:support-v4:22.0.0'
androidTestCompile 'com.android.support.test.espresso:espresso-core:2.1'

...and so will this one (without 'com.android.support.test:runner:0.2'):

compile 'com.android.support:support-v4:22.1.0'
androidTestCompile 'com.android.support.test.espresso:espresso-core:2.0'

Original Answer:

Contrary to what the Espresso documentation says, you should remove this dependency:

androidTestCompile 'com.android.support.test:runner:0.2'

As it is the cause for library version conflict.

You should also update to Android gradle plugin 1.1.1, as that version will tell you the exact version conflict, which is useful in this case.

Answer 2

One other useful tip is how to force dependency resolution to a specific version.

Here is one way:

configurations.all {
    resolutionStrategy.force 'com.android.support:support-annotations:22.0.0'
}

...and here is another:

configurations.all {
    resolutionStrategy.eachDependency { DependencyResolveDetails details ->
        if (details.requested.group == 'com.android.support') {
            details.useVersion '22.0.0'
        }
    }
}

Using either of these with com.android.support.test.espresso:espresso-core:2.1 should work.

See the Forcing consistent version for a group of libraries section in the Gradle documentation for more information.