diff --git a/java_console/build.xml b/java_console/build.xml
index adab9590b9..8256b76945 100644
--- a/java_console/build.xml
+++ b/java_console/build.xml
@@ -96,6 +96,7 @@
             <src path="../java_tools/proxy_server/src/test/java"/>
             <src path="io/src/main/java"/>
             <src path="io/src/test/java"/>
+            <src path="io/src/testFixtures/java"/>
             <src path="luaformatter/src"/>
             <src path="models/src/main/java"/>
             <src path="models/src/test/java"/>
diff --git a/java_console/io/build.gradle b/java_console/io/build.gradle
index 37c685345c..0b20f248e6 100644
--- a/java_console/io/build.gradle
+++ b/java_console/io/build.gradle
@@ -1,5 +1,6 @@
 plugins {
     id 'java-library'
+    id 'java-test-fixtures'
 }
 
 apply from: '../../android/dependencies.gradle'
@@ -29,5 +30,5 @@ dependencies {
 
     // junit 4.13 does not mix well with httpclient :(
     testImplementation group: 'junit', name: 'junit', version: '4.8.2'
-    testImplementation group: 'org.mockito', name: 'mockito-all', version: '1.10.19'
+    testFixturesImplementation group: 'org.mockito', name: 'mockito-all', version: '1.10.19'
 }
\ No newline at end of file
diff --git a/java_console/io/io.iml b/java_console/io/io.iml
index 61dae13d6f..d76e80ee0f 100644
--- a/java_console/io/io.iml
+++ b/java_console/io/io.iml
@@ -5,6 +5,7 @@
     <content url="file://$MODULE_DIR$">
       <sourceFolder url="file://$MODULE_DIR$/src/main/java" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/src/test/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testFixtures/java" isTestSource="true" />
       <excludeFolder url="file://$MODULE_DIR$/build" />
     </content>
     <orderEntry type="inheritedJdk" />
diff --git a/java_console/io/src/testFixtures/java/com/rusefi/MockitoTestHelper.java b/java_console/io/src/testFixtures/java/com/rusefi/MockitoTestHelper.java
new file mode 100644
index 0000000000..70b3d230b9
--- /dev/null
+++ b/java_console/io/src/testFixtures/java/com/rusefi/MockitoTestHelper.java
@@ -0,0 +1,9 @@
+package com.rusefi;
+
+import org.mockito.stubbing.Answer;
+
+public class MockitoTestHelper {
+    public static final Answer<?> NEGATIVE_ANSWER = invocation -> {
+        throw new UnsupportedOperationException("Not mocked " + invocation);
+    };
+}