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MockKException: Class cast exception happened while mocking generic class

See original GitHub issue

Expected Behavior

mock class

Current Behavior

every block raise io.mockk.MockKException: Class cast exception happened.

Failure Information (for bugs)

Steps to Reproduce

Preparing

$ git clone https://github.com/ganadist/VersionCodeDemo test -b mockk_cast_exception_robolectric_4.4
$ cd test

On java 8, it has no problem

$ /usr/lib/jvm/java-8-openjdk/bin/java -version
openjdk version "1.8.0_265"
OpenJDK Runtime Environment (build 1.8.0_265-b01)
OpenJDK 64-Bit Server VM (build 25.265-b01, mixed mode)

$ git checkout origin/mockk_cast_exception_robolectric_4.4~2

### pass with java8 + robolectric 4.3.1 + mockk 1.10.0
$ ./gradlew clean
$ env JAVA_HOME=/usr/lib/jvm/java-8-openjdk ./gradlew :app:testDevelopDebugUnitTest --no-build-cache

$ git checkout origin/mockk_cast_exception_robolectric_4.4~1

### pass with java8 + robolectric 4.4 + mockk 1.10.0
$ ./gradlew clean
$ env JAVA_HOME=/usr/lib/jvm/java-8-openjdk ./gradlew :app:testDevelopDebugUnitTest --no-build-cache

$ git checkout origin/mockk_cast_exception_robolectric_4.4

### pass with java8 + robolectric 4.4 + mockk 1.10.1-SNAPSHOT
$ ./gradlew clean
$ env JAVA_HOME=/usr/lib/jvm/java-8-openjdk ./gradlew :app:testDevelopDebugUnitTest --no-build-cache

On java 11 + Robolectric 4.4, mockk raise io.mockk.MockKException: Class cast exception happened.

$ /usr/lib/jvm/java-11-openjdk/bin/java -version
openjdk version "11.0.8" 2020-07-14
OpenJDK Runtime Environment (build 11.0.8+10)
OpenJDK 64-Bit Server VM (build 11.0.8+10, mixed mode)

$ git checkout origin/mockk_cast_exception_robolectric_4.4~2

### pass with java11 + robolectric 4.3.1 + mockk 1.10.0
$ ./gradlew clean
$ env JAVA_HOME=/usr/lib/jvm/java-11-openjdk ./gradlew :app:testDevelopDebugUnitTest --no-build-cache

$ git checkout origin/mockk_cast_exception_robolectric_4.4~1

### fail with java11 + robolectric 4.4 + mockk 1.10.0
$ ./gradlew clean
$ env JAVA_HOME=/usr/lib/jvm/java-11-openjdk ./gradlew :app:testDevelopDebugUnitTest --no-build-cache

$ git checkout origin/mockk_cast_exception_robolectric_4.4

### fail with java11 + robolectric 4.4 + mockk 1.10.1-SNAPSHOT
$ ./gradlew clean
$ env JAVA_HOME=/usr/lib/jvm/java-11-openjdk ./gradlew :app:testDevelopDebugUnitTest --no-build-cache

Context

Please provide any relevant information about your setup. This is important in case the issue is not reproducible except for under certain conditions.

MockK version: 1.10.0, 1.10.1-SNAPSHOT (https://github.com/mockk/mockk/commit/10f17de9645f71245e8f3e11e25f9424ab911f0d)
OS: Linux
Kotlin version: 1.3.72
JDK version: OpenJDK 11 (build 11.0.8+10)
JUnit version: 4.12
Type of test: unit test OR android instrumented test : Unittest with robolectric 4.4

It seems similar with #321, but this issue is not about chained call.

Issue Analytics

State:
Created 3 years ago
Reactions:8
Comments:15

Top GitHub Comments

7reactions

alixwarcommented, Nov 19, 2020

This is still an issue and I argue that it’s an important one since it affects all modern Android development projects

6reactions

SnexusGcommented, Apr 14, 2021

since the issue is not resolved yet, could someone tell me what might be the best workaround for this?

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