[ci/screenshots] enable discovering truncated screenshot names (#133950)

packages/kbn-test/src/failed_tests_reporter/report_failures_to_file.ts

@@ -96,7 +96,10 @@ export function reportFailuresToFile(
     );
 
     let screenshot = '';
-    const screenshotName = `${failure.name.replace(/([^ a-zA-Z0-9-]+)/g, '_')}`;
+    const truncatedName = failure.name.replace(/([^ a-zA-Z0-9-]+)/g, '_').slice(0, 80);
+    const failureNameHash = createHash('sha256').update(failure.name).digest('hex');
+    const screenshotName = `${truncatedName}-${failureNameHash}`;
+
     if (screenshotsByName[screenshotName]) {
       try {
         screenshot = readFileSync(screenshotsByName[screenshotName]).toString('base64');

test/functional/services/common/failure_debugging.ts

@@ -9,7 +9,7 @@
 import { resolve } from 'path';
 import { writeFile, mkdir } from 'fs';
 import { promisify } from 'util';
-import Uuid from 'uuid';
+import { createHash } from 'crypto';
 
 import del from 'del';
 import { FtrProviderContext } from '../../ftr_provider_context';
@@ -49,11 +49,14 @@ export async function FailureDebuggingProvider({ getService }: FtrProviderContex
   }
 
   async function onFailure(_: any, test: Test) {
+    const fullName = test.fullTitle();
+
+    // include a hash of the full title of the test in the filename so that even with truncation filenames are
+    // always unique and deterministic based on the test title
+    const hash = createHash('sha256').update(fullName).digest('hex');
+
     // Replace characters in test names which can't be used in filenames, like *
-    let name = test.fullTitle().replace(/([^ a-zA-Z0-9-]+)/g, '_');
-    if (name.length > 100) {
-      name = `truncated-${name.slice(-100)}-${Uuid.v4()}`;
-    }
+    const name = `${fullName.replace(/([^ a-zA-Z0-9-]+)/g, '_').slice(0, 80)}-${hash}`;
 
     await Promise.all([screenshots.takeForFailure(name), logCurrentUrl(), savePageHtml(name)]);
   }