test_runner: fix coverage ignore comments to exclude BRDA entries

lib/internal/test_runner/coverage.js

@@ -193,18 +193,23 @@ class TestCoverage {
           ObjectAssign(range, mapRangeToLines(range, lines));
 
           if (isBlockCoverage) {
-            ArrayPrototypePush(branchReports, {
-              __proto__: null,
-              line: range.lines[0]?.line,
-              count: range.count,
-            });
-
-            if (range.count !== 0 ||
-                range.ignoredLines === range.lines.length) {
+            // Skip branches that are completely ignored
+            if (range.ignoredLines === range.lines.length) {
+              totalBranches++;
               branchesCovered++;
+            } else {
+              ArrayPrototypePush(branchReports, {
+                __proto__: null,
+                line: range.lines[0]?.line,
+                count: range.count,
+              });
+
+              if (range.count !== 0) {
+                branchesCovered++;
+              }
+
+              totalBranches++;
             }
-
-            totalBranches++;
           }
         }
 

test/fixtures/test-runner/coverage-ignore-branch.js

@@ -0,0 +1,13 @@
+// Test fixture for issue #61586
+// Tests that node:coverage ignore next also excludes BRDA entries
+
+function getValue(condition) {
+  if (condition) {
+    return 'truthy';
+  }
+  /* node:coverage ignore next */
+  return 'falsy';
+}
+
+// Call only the truthy branch
+getValue(true);

test/parallel/test-runner-coverage-ignore-branch.js

@@ -0,0 +1,43 @@
+'use strict';
+const common = require('../common');
+const assert = require('node:assert');
+const { spawnSync } = require('node:child_process');
+const { test } = require('node:test');
+const fixtures = require('../common/fixtures');
+const skipIfNoInspector = {
+  skip: !process.features.inspector ? 'inspector disabled' : false
+};
+
+test('coverage ignore next excludes BRDA for ignored branches', skipIfNoInspector, async (t) => {
+  const fixture = fixtures.path('test-runner', 'coverage-ignore-branch.js');
+  const args = [
+    '--experimental-test-coverage',
+    '--test-reporter', 'lcov',
+    fixture,
+  ];
+  const result = spawnSync(process.execPath, args);
+  const lcovOutput = result.stdout.toString();
+
+  // Parse the LCOV output
+  const lines = lcovOutput.split('\n');
+  const brdaLines = lines.filter(l => l.startsWith('BRDA:'));
+
+  // All branches should be covered (no uncovered branches)
+  // The branch leading to the ignored code should be excluded
+  const uncoveredBranches = brdaLines.filter(l => l.endsWith(',0'));
+
+  assert.strictEqual(uncoveredBranches.length, 0,
+    `Expected no uncovered branches, but found: ${uncoveredBranches.join(', ')}`);
+
+  // Verify branch coverage is 100%
+  const brfLine = lines.find(l => l.startsWith('BRF:'));
+  const brhLine = lines.find(l => l.startsWith('BRH:'));
+  assert(brfLine, 'Should have BRF line');
+  assert(brhLine, 'Should have BRH line');
+
+  const brf = parseInt(brfLine.split(':')[1], 10);
+  const brh = parseInt(brhLine.split(':')[1], 10);
+
+  assert.strictEqual(brf, brh,
+    `Expected branch coverage to be 100% (${brh}/${brf}), but found ${brh}/${brf}`);
+});