From 2af22fb54f2caaab3b1225529a3185a4b25b40bc Mon Sep 17 00:00:00 2001
From: Michael Telatynski <7t3chguy@gmail.com>
Date: Fri, 20 Jun 2025 09:59:28 +0100
Subject: [PATCH] Add stale-screenshot-reporter.ts

---
 .../src/stale-screenshot-reporter.ts          | 88 +++++++++++++++++++
 1 file changed, 88 insertions(+)
 create mode 100644 packages/element-web-playwright-common/src/stale-screenshot-reporter.ts

diff --git a/packages/element-web-playwright-common/src/stale-screenshot-reporter.ts b/packages/element-web-playwright-common/src/stale-screenshot-reporter.ts
new file mode 100644
index 0000000000..7e2ab5b438
--- /dev/null
+++ b/packages/element-web-playwright-common/src/stale-screenshot-reporter.ts
@@ -0,0 +1,88 @@
+/*
+Copyright 2024 - 2025 New Vector Ltd.
+Copyright 2024 The Matrix.org Foundation C.I.C.
+
+SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE files in the repository root for full details.
+*/
+
+/**
+ * Test reporter which compares the reported screenshots vs those on disk to find stale screenshots
+ * Only intended to run from within GitHub Actions
+ */
+
+import { glob } from "glob";
+import { type Reporter, type TestCase } from "@playwright/test/reporter";
+import { type FullConfig } from "@playwright/test";
+
+class StaleScreenshotReporter implements Reporter {
+    private readonly snapshotRoots = new Set<string>();
+    private readonly screenshots = new Set<string>();
+    private failing = false;
+    private success = true;
+
+    public onBegin(config: FullConfig): void {
+        for (const project of config.projects) {
+            console.log("@@ found snapshotDir", project.snapshotDir);
+            this.snapshotRoots.add(project.snapshotDir);
+        }
+    }
+
+    public onTestEnd(test: TestCase): void {
+        if (!test.ok()) {
+            this.failing = true;
+        }
+        for (const annotation of test.annotations) {
+            if (annotation.type === "_screenshot" && annotation.description) {
+                this.screenshots.add(annotation.description);
+            }
+        }
+    }
+
+    private error(msg: string, file: string) {
+        if (process.env.GITHUB_ACTIONS) {
+            console.log(`::error file=${file}::${msg}`);
+        }
+        console.error(msg, file);
+        this.success = false;
+    }
+
+    public async onExit(): Promise<void> {
+        if (this.failing) return;
+        if (!this.snapshotRoots.size) {
+            this.error("No snapshot directories found, did you set the snapshotDir in your Playwright config?", "");
+            return;
+        }
+
+        const screenshotFiles = new Set<string>();
+        for (const snapshotRoot of this.snapshotRoots) {
+            const files = await glob(`**/*.png`, { cwd: snapshotRoot });
+            for (const file of files) {
+                screenshotFiles.add(file);
+            }
+        }
+
+        for (const screenshot of screenshotFiles) {
+            if (screenshot.split("-").at(-1) !== "linux.png") {
+                this.error(
+                    "Found screenshot belonging to different platform, this should not be checked in",
+                    screenshot,
+                );
+            }
+        }
+        for (const screenshot of this.screenshots) {
+            screenshotFiles.delete(screenshot);
+        }
+        if (screenshotFiles.size > 0) {
+            for (const screenshot of screenshotFiles) {
+                this.error("Stale screenshot file", screenshot);
+            }
+        }
+
+        if (!this.success) {
+            process.exit(1);
+        }
+    }
+}
+
+export default StaleScreenshotReporter;