From a866005bea8588ae24f27d90d4ed97490662a287 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=A0imon=20Brandner?= <simon.bra.ag@gmail.com>
Date: Thu, 4 Aug 2022 10:00:49 +0200
Subject: [PATCH] Add GHA for Dead Code Analysis (#9052)

---
 .github/workflows/static_analysis.yaml | 18 +++++++++
 src/hooks/useEventEmitter.ts           | 52 --------------------------
 2 files changed, 18 insertions(+), 52 deletions(-)

diff --git a/.github/workflows/static_analysis.yaml b/.github/workflows/static_analysis.yaml
index 82a99190a4..4df819375a 100644
--- a/.github/workflows/static_analysis.yaml
+++ b/.github/workflows/static_analysis.yaml
@@ -74,3 +74,21 @@ jobs:
 
       - name: Run Linter
         run: "yarn run lint:style"
+
+  analyse_dead_code:
+    name: "Analyse Dead Code"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+
+      - uses: actions/setup-node@v3
+        with:
+          cache: 'yarn'
+
+      - name: Install Deps
+        run: "scripts/ci/layered.sh"
+
+      - name: Dead Code Analysis
+        run: |
+          cd element-web 
+          yarn run analyse:unused-exports
diff --git a/src/hooks/useEventEmitter.ts b/src/hooks/useEventEmitter.ts
index 3ae011f4ab..46a7d8f184 100644
--- a/src/hooks/useEventEmitter.ts
+++ b/src/hooks/useEventEmitter.ts
@@ -68,43 +68,6 @@ export function useEventEmitter(
     );
 }
 
-/**
- * Hook to wrap an EventTarget addEventListener and removeEventListener in hook
- * lifecycle
- */
-export function useEventTarget(
-    emitter: EventTarget | undefined,
-    eventName: string,
-    handler: Handler,
-): void {
-    // Create a ref that stores handler
-    const savedHandler = useRef(handler);
-
-    // Update ref.current value if handler changes.
-    useEffect(() => {
-        savedHandler.current = handler;
-    }, [handler]);
-
-    useEffect(
-        () => {
-            // allow disabling this hook by passing a falsy emitter
-            if (!emitter) return;
-
-            // Create event listener that calls handler function stored in ref
-            const eventListener = (...args) => savedHandler.current(...args);
-
-            // Add event listener
-            emitter.addEventListener(eventName, eventListener);
-
-            // Remove event listener on cleanup
-            return () => {
-                emitter.removeEventListener(eventName, eventListener);
-            };
-        },
-        [eventName, emitter], // Re-run if eventName or emitter changes
-    );
-}
-
 type Mapper<T> = (...args: any[]) => T;
 
 export function useTypedEventEmitterState<
@@ -133,18 +96,3 @@ export function useEventEmitterState<T>(
     useEventEmitter(emitter, eventName, handler);
     return value;
 }
-
-export function useEventTargetState<T>(
-    target: EventTarget | undefined,
-    eventName: string,
-    fn: Mapper<T>,
-): T {
-    const [value, setValue] = useState<T>(fn());
-    const handler = useCallback((...args: any[]) => {
-        setValue(fn(...args));
-    }, [fn]);
-    // re-run when the emitter changes
-    useEffect(handler, [target]); // eslint-disable-line react-hooks/exhaustive-deps
-    useEventTarget(target, eventName, handler);
-    return value;
-}