1 files changed, 18 insertions, 1 deletions
diff --git a/test/common/benchmark.js b/test/common/benchmark.js
index 1fd4476ba5..f8952a8b9a 100644
--- a/test/common/benchmark.js
+++ b/test/common/benchmark.js
@@ -20,10 +20,27 @@ function runBenchmark(name, args, env) {
 
   const mergedEnv = Object.assign({}, process.env, env);
 
-  const child = fork(runjs, argv, { env: mergedEnv });
+  const child = fork(runjs, argv, { env: mergedEnv, stdio: 'pipe' });
+  child.stdout.setEncoding('utf8');
+
+  let stdout = '';
+  child.stdout.on('data', (line) => {
+    stdout += line;
+  });
+
   child.on('exit', (code, signal) => {
     assert.strictEqual(code, 0);
     assert.strictEqual(signal, null);
+    // This bit makes sure that each benchmark file is being sent settings such
+    // that the benchmark file runs just one set of options. This helps keep the
+    // benchmark tests from taking a long time to run. Therefore, each benchmark
+    // file should result in three lines of output: a blank line, a line with
+    // the name of the benchmark file, and a line with the only results that we
+    // get from testing the benchmark file.
+    assert.ok(
+      /^(?:\n.+?\n.+?\n)+$/.test(stdout),
+      `benchmark file not running exactly one configuration in test: ${stdout}`
+    );
   });
 }