fix: add NestJS discriminator guards and fix EXPOSES edge target

- NestJSControllerDetector: bail out early if no @nestjs/ import to prevent false positives on Angular controllers and generic TypeScript
- NestJSGuardsDetector: bail out early if no @nestjs/ import to prevent false positives on any TypeScript with canActivate()
- NestJSControllerDetector: add edge.setTarget(node) on EXPOSES edges — previously missing, causing all class→endpoint edges to be silently dropped by GraphBuilder

Co-Authored-By: Paperclip <noreply@paperclip.ing>

Author: aksOps

src/main/java/io/github/randomcodespace/iq/detector/typescript/NestJSControllerDetector.java

@@ -38,6 +38,8 @@ public class NestJSControllerDetector extends AbstractAntlrDetector {
     private static final Pattern FETCH_RE = Pattern.compile(
             "\\bfetch\\s*\\(\\s*['\"`]");
 
+    private static final Pattern NESTJS_IMPORT = Pattern.compile("from\\s+['\"]@nestjs/");
+
     private static final Pattern CONTROLLER_PATTERN = Pattern.compile(
             "@Controller\\(\\s*['\"`]?([^'\"`\\)\\s]*)['\"`]?\\s*\\)(?:\\s*@\\w+\\([^)]*\\))*\\s*\\n\\s*(?:export\\s+)?class\\s+(\\w+)"
     );
@@ -78,9 +80,11 @@ public DetectorResult detect(DetectorContext ctx) {
 
     @Override
     protected DetectorResult detectWithRegex(DetectorContext ctx) {
+        String text = ctx.content();
+        if (!NESTJS_IMPORT.matcher(text).find()) return DetectorResult.empty();
+
         List<CodeNode> nodes = new ArrayList<>();
         List<CodeEdge> edges = new ArrayList<>();
-        String text = ctx.content();
         String filePath = ctx.filePath();
         String moduleName = ctx.moduleName();
 
@@ -161,6 +165,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 edge.setId(classId + "->exposes->" + nodeId);
                 edge.setKind(EdgeKind.EXPOSES);
                 edge.setSourceId(classId);
+                edge.setTarget(node);
                 edges.add(edge);
             }
         }

src/main/java/io/github/randomcodespace/iq/detector/typescript/NestJSGuardsDetector.java

@@ -28,6 +28,8 @@
 @Component
 public class NestJSGuardsDetector extends AbstractAntlrDetector {
 
+    private static final Pattern NESTJS_IMPORT = Pattern.compile("from\\s+['\"]@nestjs/");
+
     private static final Pattern USE_GUARDS_PATTERN = Pattern.compile(
             "@UseGuards\\(\\s*([^)]+)\\)"
     );
@@ -67,8 +69,10 @@ public DetectorResult detect(DetectorContext ctx) {
 
     @Override
     protected DetectorResult detectWithRegex(DetectorContext ctx) {
-        List<CodeNode> nodes = new ArrayList<>();
         String text = ctx.content();
+        if (!NESTJS_IMPORT.matcher(text).find()) return DetectorResult.empty();
+
+        List<CodeNode> nodes = new ArrayList<>();
         String filePath = ctx.filePath();
         String moduleName = ctx.moduleName();
 

src/test/java/io/github/randomcodespace/iq/detector/typescript/NestJSControllerDetectorTest.java

@@ -3,6 +3,7 @@
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.detector.DetectorTestUtils;
+import io.github.randomcodespace.iq.model.EdgeKind;
 import io.github.randomcodespace.iq.model.NodeKind;
 import org.junit.jupiter.api.Test;
 
@@ -15,6 +16,7 @@ class NestJSControllerDetectorTest {
     @Test
     void detectsNestJSController() {
         String code = """
+                import { Controller, Get, Post } from '@nestjs/common';
                 @Controller('users')
                 export class UsersController {
                     @Get()
@@ -35,8 +37,42 @@ export class UsersController {
         // Endpoints
         assertTrue(result.nodes().stream().anyMatch(n ->
                 n.getKind() == NodeKind.ENDPOINT && "GET /users".equals(n.getLabel())));
-        // EXPOSES edges
+        // EXPOSES edges with valid targets
         assertEquals(3, result.edges().size());
+        assertTrue(result.edges().stream().allMatch(e ->
+                e.getKind() == EdgeKind.EXPOSES && e.getTarget() != null));
+    }
+
+    @Test
+    void noMatchWithoutNestJSImport() {
+        // Generic TypeScript with @Controller-like patterns but no @nestjs import
+        String code = """
+                @Controller('users')
+                export class UsersController {
+                    @Get()
+                    findAll() {}
+                }
+                """;
+        DetectorContext ctx = DetectorTestUtils.contextFor("src/users.controller.ts", "typescript", code);
+        DetectorResult result = detector.detect(ctx);
+        assertTrue(result.nodes().isEmpty());
+        assertTrue(result.edges().isEmpty());
+    }
+
+    @Test
+    void noMatchOnAngularComponent() {
+        // Angular also uses @Component decorator, should not match NestJS
+        String code = """
+                import { Component } from '@angular/core';
+                @Component({ selector: 'app-root', templateUrl: './app.component.html' })
+                export class AppComponent {
+                    @Get('/users')
+                    getUsers() {}
+                }
+                """;
+        DetectorContext ctx = DetectorTestUtils.contextFor("src/app.component.ts", "typescript", code);
+        DetectorResult result = detector.detect(ctx);
+        assertTrue(result.nodes().isEmpty());
     }
 
     @Test
@@ -49,8 +85,8 @@ void noMatchOnNonNestJSCode() {
 
     @Test
     void deterministic() {
-        String code = "@Controller('test')\nexport class TestController {\n    @Get()\n    find() {}\n}";
-        DetectorContext ctx = DetectorTestUtils.contextFor("typescript", code);
+        String code = "import { Controller, Get } from '@nestjs/common';\n@Controller('test')\nexport class TestController {\n    @Get()\n    find() {}\n}";
+        DetectorContext ctx = DetectorTestUtils.contextFor("src/test.controller.ts", "typescript", code);
         DetectorTestUtils.assertDeterministic(detector, ctx);
     }
 }

src/test/java/io/github/randomcodespace/iq/detector/typescript/NestJSGuardsDetectorTest.java

@@ -15,6 +15,8 @@ class NestJSGuardsDetectorTest {
     @Test
     void detectsGuardsAndRoles() {
         String code = """
+                import { Injectable, CanActivate } from '@nestjs/common';
+                import { AuthGuard } from '@nestjs/passport';
                 @UseGuards(JwtAuthGuard, RolesGuard)
                 @Roles('admin', 'user')
                 canActivate(context) {
@@ -34,6 +36,21 @@ void detectsGuardsAndRoles() {
                 n.getLabel().contains("Roles(admin, user)")));
     }
 
+    @Test
+    void noMatchWithoutNestJSImport() {
+        // Generic TypeScript with canActivate() but no @nestjs import
+        String code = """
+                class RouteGuard {
+                    canActivate(context) {
+                        return this.authService.isAuthenticated();
+                    }
+                }
+                """;
+        DetectorContext ctx = DetectorTestUtils.contextFor("src/route.guard.ts", "typescript", code);
+        DetectorResult result = detector.detect(ctx);
+        assertTrue(result.nodes().isEmpty());
+    }
+
     @Test
     void noMatchOnNonGuardCode() {
         String code = "class SomeService {}";
@@ -44,8 +61,8 @@ void noMatchOnNonGuardCode() {
 
     @Test
     void deterministic() {
-        String code = "@UseGuards(AuthGuard)\n@Roles('admin')";
-        DetectorContext ctx = DetectorTestUtils.contextFor("typescript", code);
+        String code = "import { Injectable } from '@nestjs/common';\n@UseGuards(AuthGuard)\n@Roles('admin')";
+        DetectorContext ctx = DetectorTestUtils.contextFor("src/auth.guard.ts", "typescript", code);
         DetectorTestUtils.assertDeterministic(detector, ctx);
     }
 }