🔨 fix: detect routes defined on APIRouter instances and add tests fo…

src/appDiscovery.ts

@@ -63,7 +63,8 @@ async function findAllFastAPIFiles(
     )
       continue
     const content = await vscode.workspace.fs.readFile(uri)
-    if (new TextDecoder().decode(content).includes("FastAPI(")) {
+    const text = new TextDecoder().decode(content)
+    if (text.includes("FastAPI(") || text.includes("APIRouter(")) {
       results.push(uri.toString())
     }
   }

src/test/core/routerResolver.test.ts

@@ -517,5 +517,28 @@ suite("routerResolver", () => {
         "neon router should have routes",
       )
     })
+
+    test("builds graph from standalone APIRouter-only file", async () => {
+      const result = await buildRouterGraph(
+        fixtures.routerOnly.mainPy,
+        parser,
+        fixtures.routerOnly.root,
+        nodeFileSystem,
+      )
+
+      assert.ok(result, "Should find router in APIRouter-only file")
+      assert.strictEqual(result.type, "APIRouter")
+      assert.strictEqual(result.variableName, "router")
+      assert.strictEqual(result.prefix, "/api")
+
+      // Should have 2 routes: GET /items and POST /items
+      assert.strictEqual(result.routes.length, 2)
+      const getPaths = result.routes.map((r) => `${r.method} ${r.path}`)
+      assert.ok(getPaths.includes("get /items"), "Should have GET /items route")
+      assert.ok(
+        getPaths.includes("post /items"),
+        "Should have POST /items route",
+      )
+    })
   })
 })

src/test/testUtils.ts

@@ -65,6 +65,10 @@ export const fixtures = {
     root: uri(join(fixturesPath, "error-cases")),
     mainPy: uri(join(fixturesPath, "error-cases", "main.py")),
   },
+  routerOnly: {
+    root: uri(join(fixturesPath, "router-only")),
+    mainPy: uri(join(fixturesPath, "router-only", "main.py")),
+  },
   nestedRouter: {
     root: uri(join(fixturesPath, "nested-router")),
     mainPy: uri(join(fixturesPath, "nested-router", "app", "main.py")),