Add missed mockInfoGenerator for system static objects (#2014)

Author: CaelmBleidd

utbot-framework-test/src/test/kotlin/org/utbot/examples/mock/MockStaticMethodExampleTest.kt

@@ -7,6 +7,7 @@ import org.utbot.framework.util.singleStaticMethod
 import org.utbot.framework.util.singleValue
 import org.junit.jupiter.api.Test
 import org.utbot.framework.plugin.api.CodegenLanguage
+import org.utbot.framework.plugin.api.util.id
 import org.utbot.testcheckers.eq
 import org.utbot.testing.CodeGeneration
 import org.utbot.testing.Compilation
@@ -48,4 +49,14 @@ internal class MockStaticMethodExampleTest : UtValueTestCaseChecker(
             mockStrategy = MockStrategyApi.OTHER_PACKAGES
         )
     }
+
+    @Test
+    fun testMockStaticMethodFromAlwaysMockClass() {
+        checkMocksAndInstrumentation(
+            MockStaticMethodExample::mockStaticMethodFromAlwaysMockClass,
+            eq(1),
+            coverage = DoNotCalculate,
+            additionalMockAlwaysClasses = setOf(System::class.id)
+        )
+    }
 }

utbot-framework/src/main/kotlin/org/utbot/engine/Traverser.kt

@@ -634,8 +634,8 @@ class Traverser(
     ): Pair<SymbolicStateUpdate, SymbolicValue?> {
         val jClass = type.id.jClass
 
-        // symbolic value for enum class itself
-        val enumClassValue = findOrCreateStaticObject(type)
+        // symbolic value for enum class itself, we don't want to have mocks for this value
+        val enumClassValue = findOrCreateStaticObject(type, mockInfoGenerator = null)
 
         // values for enum constants
         val enumConstantConcreteValues = jClass.enumConstants.filterIsInstance<Enum<*>>()
@@ -708,8 +708,10 @@ class Traverser(
         val initializedFieldUpdate =
             MemoryUpdate(initializedStaticFields = persistentHashSetOf(fieldId))
 
+        val mockInfoGenerator = UtMockInfoGenerator { addr -> UtStaticObjectMockInfo(declaringClass.id, addr) }
+
         val objectUpdate = objectUpdate(
-            instance = findOrCreateStaticObject(declaringClass.type),
+            instance = findOrCreateStaticObject(declaringClass.type, mockInfoGenerator),
             field = field,
             value = valueToExpression(symbolicValue, field.type)
         )
@@ -2187,7 +2189,7 @@ class Traverser(
      */
     private fun findOrCreateStaticObject(
         classType: RefType,
-        mockInfoGenerator: UtMockInfoGenerator? = null
+        mockInfoGenerator: UtMockInfoGenerator?
     ): ObjectValue {
         val fromMemory = locateStaticObject(classType)
 

utbot-sample/src/main/java/org/utbot/examples/mock/MockStaticMethodExample.java

@@ -11,4 +11,8 @@ public int useStaticMethod() {
 
         return 0;
     }
+
+    public void mockStaticMethodFromAlwaysMockClass() {
+        System.out.println("example");
+    }
 }