call graph fix + tests

2026-06-19 21:57:30 +02:00
parent bf9208d529
commit ab37eb5d40
12 changed files with 1141 additions and 128 deletions
--- a/state_machine_exporter/src/test/java/click/kamil/springstatemachineexporter/analysis/service/CallGraphBuilderTest.java
+++ b/state_machine_exporter/src/test/java/click/kamil/springstatemachineexporter/analysis/service/CallGraphBuilderTest.java
@@ -215,8 +215,743 @@ class CallGraphBuilderTest {

        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));

+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        assertThat(chain.getTriggerPoint().getPolymorphicEvents())
+            .as("Resolved event was: " + chain.getTriggerPoint().getEvent())
+            .containsExactlyInAnyOrder("OrderEvents.PAY");
+    }
+
+    @Test
+    void shouldResolvePolymorphicInheritanceAcrossChain() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent(RichOrderEvent domainEvent) {
+                        doProcessOrderEvent(domainEvent);
+                    }
+                    
+                    private void doProcessOrderEvent(RichOrderEvent domainEvent) {
+                        OrderEvents eventType = assertSupportedOrderEvent(domainEvent.getType());
+                        service.updateOrderState(eventType);
+                    }
+                    
+                    private OrderEvents assertSupportedOrderEvent(OrderEvents e) {
+                        return e;
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {
+                        // sendEvent
+                    }
+                }
+                
+                interface RichOrderEvent {
+                    OrderEvents getType();
+                }
+                
+                class CancelOrderEvent implements RichOrderEvent {
+                    public OrderEvents getType() { return OrderEvents.CANCELLED; }
+                }
+                
+                class ReceiveOrderEvent implements RichOrderEvent {
+                    public OrderEvents getType() { return OrderEvents.RECEIVED; }
+                }
+                
+                enum OrderEvents { CREATE, PAY, CANCELLED, RECEIVED }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_poly");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        assertThat(chain.getTriggerPoint().getPolymorphicEvents())
+            .as("Resolved event was: " + chain.getTriggerPoint().getEvent())
+            .containsExactlyInAnyOrder("OrderEvents.CANCELLED", "OrderEvents.RECEIVED");
+    }
+
+    @Test
+    void shouldUnwrapDeepMethodWrappers() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent(RichOrderEvent domainEvent) {
+                        OrderEvents eventType = wrap3(wrap2(wrap1(domainEvent.getType())));
+                        service.updateOrderState(eventType);
+                    }
+                    
+                    private OrderEvents wrap1(OrderEvents e) { return e; }
+                    private OrderEvents wrap2(OrderEvents e) { return e; }
+                    private OrderEvents wrap3(OrderEvents e) { return e; }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) { }
+                }
+                
+                class RichOrderEvent {
+                    public OrderEvents getType() { return OrderEvents.CREATE; }
+                }
+                
+                enum OrderEvents { CREATE }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_deep_wrap");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        assertThat(chain.getTriggerPoint().getPolymorphicEvents())
+            .as("Resolved event was: " + chain.getTriggerPoint().getEvent())
+            .containsExactlyInAnyOrder("OrderEvents.CREATE");
+    }
+
+    @Test
+    void shouldResolvePolymorphicInheritanceThroughDelegation() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent(BaseEvent domainEvent) {
+                        service.updateOrderState(domainEvent.getType());
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {}
+                }
+                
+                interface BaseEvent {
+                    OrderEvents getType();
+                }
+                
+                abstract class AbstractEvent implements BaseEvent {
+                    protected OrderEvents internalGetType() {
+                        return OrderEvents.PAY;
+                    }
+                }
+                
+                class ConcreteEvent extends AbstractEvent {
+                    public OrderEvents getType() { 
+                        return internalGetType(); 
+                    }
+                }
+                
+                class AnotherConcreteEvent implements BaseEvent {
+                    public OrderEvents getType() {
+                        return delegateToHelper();
+                    }
+                    private OrderEvents delegateToHelper() {
+                        return OrderEvents.CANCELLED;
+                    }
+                }
+                
+                enum OrderEvents { PAY, CANCELLED }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_poly_delegation");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        assertThat(chain.getTriggerPoint().getPolymorphicEvents())
+            .containsExactlyInAnyOrder("OrderEvents.PAY", "OrderEvents.CANCELLED");
+    }
+
+    @Test
+    void shouldHandleMissingImplementationsGracefully() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent(UnknownEvent domainEvent) {
+                        service.updateOrderState(domainEvent.getType());
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {}
+                }
+                
+                // UnknownEvent is not defined in the source (e.g. from a third-party library)
+                
+                enum OrderEvents { CREATE }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_missing_impl");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
        assertThat(chains).hasSize(1);
        CallChain chain = chains.get(0);
        assertThat(chain.getTriggerPoint().getEvent()).isEqualTo("domainEvent.getType()");
+        assertThat(chain.getTriggerPoint().getPolymorphicEvents()).isNullOrEmpty();
+    }
+
+    @Test
+    void shouldTraceMultipleLocalVariableAssignments() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent(RichOrderEvent domainEvent) {
+                        OrderEvents type1 = domainEvent.getType();
+                        OrderEvents type2 = type1;
+                        OrderEvents type3 = type2;
+                        service.updateOrderState(type3);
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {}
+                }
+                
+                class RichOrderEvent {
+                    public OrderEvents getType() { return OrderEvents.RECEIVED; }
+                }
+                
+                enum OrderEvents { RECEIVED }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_multiple_assign");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        assertThat(chain.getTriggerPoint().getPolymorphicEvents())
+            .containsExactlyInAnyOrder("OrderEvents.RECEIVED");
+    }
+
+    @Test
+    void shouldResolveMethodInheritedFromAbstractBaseClass() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent(BaseEvent domainEvent) {
+                        service.updateOrderState(domainEvent.getType());
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {}
+                }
+                
+                interface BaseEvent {
+                    OrderEvents getType();
+                }
+                
+                abstract class AbstractEvent implements BaseEvent {
+                    public OrderEvents getType() {
+                        return OrderEvents.PAY;
+                    }
+                }
+                
+                // Concrete subclass inherits getType() but doesn't override it!
+                class InheritingEvent extends AbstractEvent {
+                }
+                
+                enum OrderEvents { PAY }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_inherited");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        assertThat(chain.getTriggerPoint().getPolymorphicEvents())
+            .containsExactlyInAnyOrder("OrderEvents.PAY");
+    }
+
+    @Test
+    void shouldStopTracingRecursiveMethodsGracefully() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent(RecursiveEvent domainEvent) {
+                        service.updateOrderState(domainEvent.getType());
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {}
+                }
+                
+                class RecursiveEvent {
+                    public OrderEvents getType() {
+                        return this.getType();
+                    }
+                }
+                
+                enum OrderEvents { PAY }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_recursive");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        // Should safely complete without stack overflow and return an empty result
+        assertThat(chain.getTriggerPoint().getEvent()).isEqualTo("domainEvent.getType()");
+        assertThat(chain.getTriggerPoint().getPolymorphicEvents()).isEmpty();
+    }
+
+    @Test
+    void shouldHandleChainedMethodCallsGracefully() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent(EventWrapper wrapper) {
+                        service.updateOrderState(wrapper.getEvent().getType());
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {}
+                }
+                
+                class EventWrapper {
+                    public RichEvent getEvent() { return new RichEvent(); }
+                }
+                
+                class RichEvent {
+                    public OrderEvents getType() { return OrderEvents.PAY; }
+                }
+                
+                enum OrderEvents { PAY }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_chained");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        // It might not fully resolve chained method calls, but it must not crash!
+        assertThat(chain.getTriggerPoint().getEvent()).isEqualTo("wrapper.getEvent().getType()");
+    }
+
+    @Test
+    void shouldTraceStaticFieldReferences() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private static final OrderEvents CONSTANT_EVENT = OrderEvents.CANCELLED;
+                    private OrderService service;
+                    public void processOrderEvent() {
+                        service.updateOrderState(CONSTANT_EVENT);
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {}
+                }
+                
+                enum OrderEvents { CANCELLED }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_static_field");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        assertThat(chain.getTriggerPoint().getEvent()).isEqualTo("OrderEvents.CANCELLED");
+    }
+
+    @Test
+    void shouldHandleAnonymousInnerClassesGracefully() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent() {
+                        RichEvent event = new RichEvent() {
+                            public OrderEvents getType() {
+                                return OrderEvents.CREATE;
+                            }
+                        };
+                        service.updateOrderState(event.getType());
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {}
+                }
+                
+                interface RichEvent {
+                    OrderEvents getType();
+                }
+                
+                enum OrderEvents { CREATE }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_anonymous");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        // It successfully traces the local variable 'event' to its anonymous class initializer
+        assertThat(chain.getTriggerPoint().getEvent()).startsWith("new RichEvent(){");
+        assertThat(chain.getTriggerPoint().getEvent()).endsWith(".getType()");
+    }
+
+    @Test
+    void shouldLinkCallsInsideLambdasToEnclosingMethod() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent() {
+                        Runnable r = () -> service.updateOrderState(OrderEvents.PAY);
+                        r.run();
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {}
+                }
+                
+                enum OrderEvents { PAY }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_lambda_scope");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        assertThat(chain.getTriggerPoint().getEvent()).isEqualTo("OrderEvents.PAY");
+    }
+
+    @Test
+    void shouldHandleTernaryOperatorsGracefully() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent(boolean flag) {
+                        OrderEvents event = flag ? OrderEvents.PAY : OrderEvents.CANCELLED;
+                        service.updateOrderState(event);
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {}
+                }
+                
+                enum OrderEvents { PAY, CANCELLED }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_ternary");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        // It should gracefully fallback to the string representation of the ternary operator
+        assertThat(chain.getTriggerPoint().getEvent()).isEqualTo("flag ? OrderEvents.PAY : OrderEvents.CANCELLED");
+    }
+
+    @Test
+    void shouldTraceLastTextualAssignmentInTryCatchBlocks() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent() {
+                        OrderEvents event;
+                        try {
+                            event = OrderEvents.PAY;
+                        } catch (Exception e) {
+                            event = OrderEvents.CANCELLED;
+                        }
+                        service.updateOrderState(event);
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {}
+                }
+                
+                enum OrderEvents { PAY, CANCELLED }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_try_catch");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        // The ASTVisitor picks up Assignments in textual order. 
+        // CANCELLED is the last one textually in the method.
+        assertThat(chain.getTriggerPoint().getEvent()).isEqualTo("OrderEvents.CANCELLED");
+    }
+
+    @Test
+    void shouldTraceArrayAndCollectionAccessGracefully() throws IOException {
+        String source = """
+                package com.example;
+                public class OrderController {
+                    private OrderService service;
+                    public void processOrderEvent() {
+                        OrderEvents[] events = new OrderEvents[]{OrderEvents.PAY};
+                        service.updateOrderState(events[0]);
+                    }
+                }
+                
+                class OrderService {
+                    public void updateOrderState(OrderEvents event) {}
+                }
+                
+                enum OrderEvents { PAY }
+                """;
+        Path tempDir = Files.createTempDirectory("callgraph_test_array");
+        Files.writeString(tempDir.resolve("OrderConfig.java"), source);
+
+        CodebaseContext context = new CodebaseContext();
+        context.scan(tempDir);
+
+        CallGraphBuilder builder = new CallGraphBuilder(context);
+
+        EntryPoint entryPoint = EntryPoint.builder()
+                .className("com.example.OrderController")
+                .methodName("processOrderEvent")
+                .build();
+
+        TriggerPoint trigger = TriggerPoint.builder()
+                .className("com.example.OrderService")
+                .methodName("updateOrderState")
+                .event("event")
+                .build();
+
+        List<CallChain> chains = builder.findChains(List.of(entryPoint), List.of(trigger));
+
+        assertThat(chains).hasSize(1);
+        CallChain chain = chains.get(0);
+        // We don't dynamically resolve array indexes, but it shouldn't crash.
+        // It returns the array access expression as a string.
+        assertThat(chain.getTriggerPoint().getEvent()).isEqualTo("events[0]");
    }
 }
--- a/state_machine_exporter/src/test/resources/golden/EnterpriseStateMachineConfig/EnterpriseStateMachineConfig.json
+++ b/state_machine_exporter/src/test/resources/golden/EnterpriseStateMachineConfig/EnterpriseStateMachineConfig.json
@@ -8,7 +8,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 17
+      "lineNumber" : 17,
+      "polymorphicEvents" : null
    }, {
      "event" : "PLACE_ORDER",
      "className" : "click.kamil.examples.enterprise.service.OrderServiceImpl",
@@ -17,7 +18,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 16
+      "lineNumber" : 16,
+      "polymorphicEvents" : null
    }, {
      "event" : "CANCEL_ORDER",
      "className" : "click.kamil.examples.enterprise.service.OrderServiceImpl",
@@ -26,7 +28,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 21
+      "lineNumber" : 21,
+      "polymorphicEvents" : null
    }, {
      "event" : "PAY_ORDER",
      "className" : "click.kamil.examples.enterprise.service.ReactivePaymentService",
@@ -35,7 +38,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 18
+      "lineNumber" : 18,
+      "polymorphicEvents" : null
    }, {
      "event" : "SHIP_ORDER",
      "className" : "click.kamil.examples.enterprise.messaging.ShippingJmsListener",
@@ -44,7 +48,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 17
+      "lineNumber" : 17,
+      "polymorphicEvents" : null
    }, {
      "event" : "RETURN_ORDER",
      "className" : "click.kamil.examples.enterprise.messaging.ReturnsRabbitListener",
@@ -53,7 +58,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 17
+      "lineNumber" : 17,
+      "polymorphicEvents" : null
    } ],
    "entryPoints" : [ {
      "type" : "REST",
@@ -185,7 +191,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 16
+        "lineNumber" : 16,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -219,7 +226,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 21
+        "lineNumber" : 21,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -248,7 +256,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 17
+        "lineNumber" : 17,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : null
@@ -278,7 +287,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 18
+        "lineNumber" : 18,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -312,7 +322,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 17
+        "lineNumber" : 17,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -346,7 +357,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 17
+        "lineNumber" : 17,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
--- a/state_machine_exporter/src/test/resources/golden/ExtendedStateMachineConfig/ExtendedStateMachineConfig.json
+++ b/state_machine_exporter/src/test/resources/golden/ExtendedStateMachineConfig/ExtendedStateMachineConfig.json
@@ -8,7 +8,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 34
+      "lineNumber" : 34,
+      "polymorphicEvents" : null
    }, {
      "event" : "AUDIT_EVENT",
      "className" : "click.kamil.examples.statemachine.extended.web.AuditInterceptor",
@@ -17,7 +18,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 16
+      "lineNumber" : 16,
+      "polymorphicEvents" : null
    }, {
      "event" : "EXTERNAL_TRIGGER",
      "className" : "click.kamil.examples.statemachine.extended.service.OrderService",
@@ -26,7 +28,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 19
+      "lineNumber" : 19,
+      "polymorphicEvents" : null
    }, {
      "event" : "SUBMIT_EVENT",
      "className" : "click.kamil.examples.statemachine.extended.service.OrderService",
@@ -35,7 +38,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 20
+      "lineNumber" : 20,
+      "polymorphicEvents" : null
    }, {
      "event" : "CANCEL_EVENT",
      "className" : "click.kamil.examples.statemachine.extended.service.OrderService",
@@ -44,7 +48,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 25
+      "lineNumber" : 25,
+      "polymorphicEvents" : null
    }, {
      "event" : "[LIFECYCLE:RESTORE]",
      "className" : "click.kamil.examples.statemachine.extended.service.OrderService",
@@ -53,7 +58,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 29
+      "lineNumber" : 29,
+      "polymorphicEvents" : null
    }, {
      "event" : "REACTIVE_EVENT",
      "className" : "click.kamil.examples.statemachine.extended.service.ReactiveOrderService",
@@ -62,7 +68,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 18
+      "lineNumber" : 18,
+      "polymorphicEvents" : null
    } ],
    "entryPoints" : [ {
      "type" : "REST",
@@ -160,7 +167,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 19
+        "lineNumber" : 19,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -190,7 +198,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 20
+        "lineNumber" : 20,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -220,7 +229,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 25
+        "lineNumber" : 25,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -250,7 +260,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 34
+        "lineNumber" : 34,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -284,7 +295,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 29
+        "lineNumber" : 29,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : "orderId",
      "matchedTransitions" : null
@@ -314,7 +326,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 18
+        "lineNumber" : 18,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -343,7 +356,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 16
+        "lineNumber" : 16,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
--- a/state_machine_exporter/src/test/resources/golden/ExtendedStateMachineConfig_PROD/ExtendedStateMachineConfig.json
+++ b/state_machine_exporter/src/test/resources/golden/ExtendedStateMachineConfig_PROD/ExtendedStateMachineConfig.json
@@ -8,7 +8,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 34
+      "lineNumber" : 34,
+      "polymorphicEvents" : null
    }, {
      "event" : "AUDIT_EVENT",
      "className" : "click.kamil.examples.statemachine.extended.web.AuditInterceptor",
@@ -17,7 +18,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 16
+      "lineNumber" : 16,
+      "polymorphicEvents" : null
    }, {
      "event" : "EXTERNAL_TRIGGER",
      "className" : "click.kamil.examples.statemachine.extended.service.OrderService",
@@ -26,7 +28,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 19
+      "lineNumber" : 19,
+      "polymorphicEvents" : null
    }, {
      "event" : "SUBMIT_EVENT",
      "className" : "click.kamil.examples.statemachine.extended.service.OrderService",
@@ -35,7 +38,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 20
+      "lineNumber" : 20,
+      "polymorphicEvents" : null
    }, {
      "event" : "CANCEL_EVENT",
      "className" : "click.kamil.examples.statemachine.extended.service.OrderService",
@@ -44,7 +48,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 25
+      "lineNumber" : 25,
+      "polymorphicEvents" : null
    }, {
      "event" : "[LIFECYCLE:RESTORE]",
      "className" : "click.kamil.examples.statemachine.extended.service.OrderService",
@@ -53,7 +58,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 29
+      "lineNumber" : 29,
+      "polymorphicEvents" : null
    }, {
      "event" : "REACTIVE_EVENT",
      "className" : "click.kamil.examples.statemachine.extended.service.ReactiveOrderService",
@@ -62,7 +68,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 18
+      "lineNumber" : 18,
+      "polymorphicEvents" : null
    } ],
    "entryPoints" : [ {
      "type" : "REST",
@@ -160,7 +167,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 19
+        "lineNumber" : 19,
+        "polymorphicEvents" : null
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      "matchedTransitions" : [ {
@@ -190,7 +198,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 20
+        "lineNumber" : 20,
+        "polymorphicEvents" : null
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      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -220,7 +229,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 25
+        "lineNumber" : 25,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -250,7 +260,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 34
+        "lineNumber" : 34,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -284,7 +295,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 29
+        "lineNumber" : 29,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : "orderId",
      "matchedTransitions" : null
@@ -314,7 +326,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 18
+        "lineNumber" : 18,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -343,7 +356,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 16
+        "lineNumber" : 16,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
--- a/state_machine_exporter/src/test/resources/golden/InheritanceStateMachineConfig/InheritanceStateMachineConfig.json
+++ b/state_machine_exporter/src/test/resources/golden/InheritanceStateMachineConfig/InheritanceStateMachineConfig.json
@@ -8,7 +8,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 15
+      "lineNumber" : 15,
+      "polymorphicEvents" : null
    } ],
    "entryPoints" : [ {
      "type" : "REST",
@@ -55,7 +56,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 15
+        "lineNumber" : 15,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
--- a/state_machine_exporter/src/test/resources/golden/MavenOrderStateMachine/MavenOrderStateMachine.json
+++ b/state_machine_exporter/src/test/resources/golden/MavenOrderStateMachine/MavenOrderStateMachine.json
@@ -8,7 +8,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 40
+      "lineNumber" : 40,
+      "polymorphicEvents" : null
    }, {
      "event" : "ORDER_EVENT",
      "className" : "click.kamil.maven.core.MavenOrderStateMachine.OrderService",
@@ -17,7 +18,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 52
+      "lineNumber" : 52,
+      "polymorphicEvents" : null
    } ],
    "entryPoints" : [ {
      "type" : "REST",
@@ -103,7 +105,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 40
+        "lineNumber" : 40,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
--- a/state_machine_exporter/src/test/resources/golden/OrderStateMachineConfig/OrderStateMachineConfig.json
+++ b/state_machine_exporter/src/test/resources/golden/OrderStateMachineConfig/OrderStateMachineConfig.json
@@ -8,7 +8,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 18
+      "lineNumber" : 18,
+      "polymorphicEvents" : null
    } ],
    "entryPoints" : [ {
      "type" : "REST",
@@ -67,7 +68,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 18
+        "lineNumber" : 18,
+        "polymorphicEvents" : null
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
--- a/state_machine_exporter/src/test/resources/golden/StateMachineConfig/StateMachineConfig.json
+++ b/state_machine_exporter/src/test/resources/golden/StateMachineConfig/StateMachineConfig.json
@@ -8,7 +8,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 25
+      "lineNumber" : 25,
+      "polymorphicEvents" : null
    }, {
      "event" : "eventProvider",
      "className" : "click.kamil.service.StateMachineServiceImpl",
@@ -17,7 +18,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 50
+      "lineNumber" : 50,
+      "polymorphicEvents" : null
    }, {
      "event" : "customMessage",
      "className" : "click.kamil.service.StateMachineServiceImpl",
@@ -26,7 +28,8 @@
      "sourceModule" : null,
      "stateMachineId" : null,
      "sourceState" : null,
-      "lineNumber" : 78
+      "lineNumber" : 78,
+      "polymorphicEvents" : null
    } ],
    "entryPoints" : [ {
      "type" : "REST",
@@ -140,7 +143,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 25
+        "lineNumber" : 25,
+        "polymorphicEvents" : [ ]
      },
      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -170,7 +174,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 25
+        "lineNumber" : 25,
+        "polymorphicEvents" : [ ]
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      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -200,7 +205,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 25
+        "lineNumber" : 25,
+        "polymorphicEvents" : [ ]
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      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -234,7 +240,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 25
+        "lineNumber" : 25,
+        "polymorphicEvents" : [ ]
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      "contextMachineId" : null,
      "matchedTransitions" : [ {
@@ -268,7 +275,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 78
+        "lineNumber" : 78,
+        "polymorphicEvents" : [ ]
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      "matchedTransitions" : [ {
@@ -302,7 +310,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
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-        "lineNumber" : 25
+        "lineNumber" : 25,
+        "polymorphicEvents" : [ ]
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      "matchedTransitions" : [ {
@@ -336,7 +345,8 @@
        "sourceModule" : null,
        "stateMachineId" : null,
        "sourceState" : null,
-        "lineNumber" : 50
+        "lineNumber" : 50,
+        "polymorphicEvents" : [ ]
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      "contextMachineId" : null,
      "matchedTransitions" : [ {