Support UtMock for fuzzer tests (#1517)

Author: mmvpm

utbot-api/src/main/java/org/utbot/api/exception/UtMockAssumptionViolatedException.java

@@ -0,0 +1,8 @@
+package org.utbot.api.exception;
+
+public class UtMockAssumptionViolatedException extends RuntimeException {
+    @Override
+    public String getMessage() {
+        return "UtMock assumption violated";
+    }
+}

utbot-api/src/main/java/org/utbot/api/mock/UtMock.java

@@ -1,5 +1,7 @@
 package org.utbot.api.mock;
 
+import org.utbot.api.exception.UtMockAssumptionViolatedException;
+
 public class UtMock {
     public static <T> T makeSymbolic() {
         return makeSymbolic(false);
@@ -14,14 +16,14 @@ public static <T> T makeSymbolic(boolean isNullable) {
     public static void assume(boolean predicate) {
         // to use compilers checks, i.e. for possible NPE
         if (!predicate) {
-            throw new RuntimeException();
+            throw new UtMockAssumptionViolatedException();
         }
     }
 
     @SuppressWarnings("unused")
     public static void assumeOrExecuteConcretely(boolean predicate) {
         // In oppose to assume, we don't have predicate check here
-        // to avoid RuntimeException during concrete execution
+        // to avoid UtMockAssumptionViolatedException during concrete execution
     }
 
     @SuppressWarnings("unused")

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

@@ -7,6 +7,7 @@ import mu.KotlinLogging
 import org.utbot.analytics.EngineAnalyticsContext
 import org.utbot.analytics.FeatureProcessor
 import org.utbot.analytics.Predictors
+import org.utbot.api.exception.UtMockAssumptionViolatedException
 import org.utbot.common.bracket
 import org.utbot.common.debug
 import org.utbot.engine.MockStrategy.NO_MOCKS
@@ -366,6 +367,11 @@ class UtBotSymbolicEngine(
             // in case an exception occurred from the concrete execution
             concreteExecutionResult ?: return@runJavaFuzzing BaseFeedback(result = Trie.emptyNode(), control = Control.PASS)
 
+            if (concreteExecutionResult.result.exceptionOrNull() is UtMockAssumptionViolatedException) {
+                logger.debug { "Generated test case by fuzzer violates the UtMock assumption" }
+                return@runJavaFuzzing BaseFeedback(result = Trie.emptyNode(), control = Control.PASS)
+            }
+
             val coveredInstructions = concreteExecutionResult.coverage.coveredInstructions
             var trieNode: Trie.Node<Instruction>? = null
             if (coveredInstructions.isNotEmpty()) {