feat(report): copy failure details button on failed tests

CHANGELOG.md

@@ -9,6 +9,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/).
 
 ### Unreleased
 
+- **HTML report: "Copy failure details" button** — failed tests with an error now have a button in the expanded detail row (and on the Failures tab) that copies the test id, error message and stack trace to the clipboard, with brief "Copied" feedback. Falls back to `execCommand('copy')` when `navigator.clipboard` is unavailable (e.g. some `file://` setups). (#216)
+
 - **Fix: `@PreCondition` session restore on a fresh browser** — the cached cookies and localStorage were silently dropped when the next test started on `about:blank`, so only the first test per thread was logged in. Restore now navigates to the origin the session was captured on first.
 
 - **LambdaTest cloud provider** — `execution.mode: lambdatest` now creates W3C

src/main/java/com/seleniumboot/reporting/HtmlReportGenerator.java

@@ -402,6 +402,10 @@ private static String buildRow(JsonNode test, int rowIndex, String groupId, bool
                     + (test.has("failureCategory") ? buildFailureWhy(test) : "");
             String errorHtml     = whyHtml + (errorMsg != null ? "<div class=\"error-msg\">" + escapeHtml(errorMsg) + "</div>" : "");
             String traceHtml     = stackTrace    != null ? "<pre class=\"stack-trace\">"    + escapeHtml(stackTrace) + "</pre>" : "";
+            String copyBtn       = "FAILED".equals(status) && (errorMsg != null || stackTrace != null)
+                    ? "<button type=\"button\" class=\"copy-failure-btn\" data-test-id=\"" + escapeHtml(rawTestId)
+                      + "\" onclick=\"copyFailure(this, event)\">Copy failure details</button>"
+                    : "";
             String recordingHtml = recordingPath != null ? buildRecordingCell(recordingPath) : "";
             String traceLink     = tracePath     != null ? buildTraceLink(tracePath) : "";
             String sessionLink   = sessionUrl    != null ? buildSessionLink(sessionUrl) : "";
@@ -415,7 +419,7 @@ private static String buildRow(JsonNode test, int rowIndex, String groupId, bool
             String detailDisplay = detailHidden ? " style=\"display:none\"" : "";
             detailRow = "<tr class=\"detail-row group-member\" data-group=\"" + groupKey + "\" id=\"detail-" + rowIndex + "\"" + detailDisplay + ">"
                     + "<td colspan=\"" + colspan + "\"><div class=\"detail-panel\">"
-                    + failureDetail + perfHtml + sessionLink + traceLink + stepsSection + recordingHtml + aiHtml + errorHtml + traceHtml
+                    + copyBtn + failureDetail + perfHtml + sessionLink + traceLink + stepsSection + recordingHtml + aiHtml + errorHtml + traceHtml
                     + "</div></td>"
                     + "</tr>";
         }

src/main/resources/report/report.css

@@ -298,6 +298,8 @@
         /* ── Detail / error panel ── */
         .detail-row td { padding: 0; }
         .detail-panel { padding: 16px 24px; background: var(--surface2); border-top: 2px solid var(--bad); }
+        .copy-failure-btn { float: right; margin: 0 0 8px 12px; border: 1px solid var(--border); background: var(--surface); color: var(--text-secondary); border-radius: 12px; padding: 2px 12px; font-size: 12px; cursor: pointer; }
+        .copy-failure-btn:hover { background: var(--primary); color: #fff; border-color: var(--primary); }
         .error-msg { font-size: 13px; font-weight: 600; color: var(--bad); margin-bottom: 10px; }
         .failure-group { padding: 10px 0; border-bottom: 1px solid var(--border); }
         .failure-group:last-child { border-bottom: 0; }

src/main/resources/report/report.js

@@ -164,3 +164,39 @@ function applySearch() {
         hdr.style.display = visibleGroups.has(groupId) ? '' : 'none';
     });
 }
+
+// ── Copy failure details ──
+function copyFailure(btn, event) {
+    if (event) event.stopPropagation();
+    const panel = btn.closest('.detail-panel');
+    const err   = panel.querySelector('.error-msg');
+    const trace = panel.querySelector('.stack-trace');
+    const text  = [
+        'Test: ' + btn.getAttribute('data-test-id'),
+        err   ? 'Error: ' + err.textContent : '',
+        trace ? '\n' + trace.textContent : ''
+    ].filter(Boolean).join('\n');
+    const done = ok => {
+        const label = btn.getAttribute('data-label') || btn.textContent;
+        btn.setAttribute('data-label', label);
+        btn.textContent = ok ? 'Copied' : 'Copy failed';
+        setTimeout(() => { btn.textContent = label; }, 1500);
+    };
+    const fallback = () => {
+        const ta = document.createElement('textarea');
+        ta.value = text;
+        ta.style.position = 'fixed';
+        ta.style.opacity = '0';
+        document.body.appendChild(ta);
+        ta.select();
+        let ok = false;
+        try { ok = document.execCommand('copy'); } catch (e) {}
+        document.body.removeChild(ta);
+        done(ok);
+    };
+    if (navigator.clipboard && window.isSecureContext) {
+        navigator.clipboard.writeText(text).then(() => done(true), fallback);
+    } else {
+        fallback();
+    }
+}

src/test/java/com/seleniumboot/reporting/HtmlReportGeneratorTest.java

@@ -283,4 +283,21 @@ public void buildHtml_tagWithQuote_renderedSafelyWithDataTag() throws Exception
         assertFalse(reportHtml.contains("filterByTag('it's'"));
         assertFalse(reportHtml.contains("filterByTag('x');alert(1);//'"));
     }
+
+    @Test
+    public void copyFailureButton_onlyOnFailedTestsWithErrorDetail() throws Exception {
+        String json = """
+        {"totalTests":3,"passedTests":1,"failedTests":1,"skippedTests":1,"passRate":33.3,"tests":[
+          {"testId":"a.A.ok","status":"PASSED","testLogicMs":1,"totalMs":1,"stepsNote":"x","description":"d","performanceMetrics":{"pageLoadMs":1}},
+          {"testId":"a.A.bad<x>","status":"FAILED","testLogicMs":1,"totalMs":1,"errorMessage":"boom","stackTrace":"at a.b"},
+          {"testId":"a.A.skip","status":"SKIPPED","testLogicMs":1,"totalMs":1,"errorMessage":"skipped because"}
+        ]}""";
+        String reportHtml = HtmlReportGenerator.buildHtml(new ObjectMapper().readTree(json));
+        String body = reportHtml.substring(reportHtml.indexOf("<tbody"));
+        assertFalse(body.contains("data-test-id=\"a.A.ok\""), "no button on passed tests");
+        assertFalse(body.contains("data-test-id=\"a.A.skip\""), "no button on skipped tests");
+        assertTrue(body.contains("data-test-id=\"a.A.bad&lt;x&gt;\""), "test id is escaped in the attribute");
+        assertTrue(reportHtml.contains("function copyFailure("));
+        assertTrue(reportHtml.contains("document.execCommand('copy')"), "file:// fallback present");
+    }
 }