log gas cost at the end of each suite

lib/tests/reporter.js

@@ -9,10 +9,12 @@ class EmbarkSpec extends Base {
     self.embarkEvents = options.reporterOptions.events;
     let indents = 0;
     let n = 0;
+    self.stats.gasCost = 0;
 
     function onContractReceipt(receipt) {
-      console.log(receipt.className, receipt.gasUsed);
+      self.stats.gasCost += receipt.gasUsed;
     }
+
     self.embarkEvents.on("deploy:contract:receipt", onContractReceipt);
 
     function indent() {
@@ -62,11 +64,48 @@ class EmbarkSpec extends Base {
       console.log(indent() + color('fail', '  %d) %s'), ++n, test.title);
     });
 
-    runner.once('end', function() {
+    runner.once('end', function () {
+      runner.removeAllListeners();
       self.embarkEvents.removeListener("deploy:contract:receipt", onContractReceipt);
       self.epilogue();
     });
   }
+
+  epilogue() {
+    const stats = this.stats;
+    let fmt;
+
+    console.log();
+
+    // passes
+    fmt = color('bright pass', ' ') +
+      color('green', ' %d passing') +
+      color('light', ' (%s gas)');
+
+    console.log(fmt,
+      stats.passes || 0,
+      stats.gasCost);
+
+    // pending
+    if (stats.pending) {
+      fmt = color('pending', ' ') +
+        color('pending', ' %d pending');
+
+      console.log(fmt, stats.pending);
+    }
+
+    // failures
+    if (stats.failures) {
+      fmt = color('fail', '  %d failing');
+
+      console.log(fmt, stats.failures);
+
+      Base.list(this.failures);
+      console.log();
+    }
+
+    console.log();
+  }
 }
 
 module.exports = EmbarkSpec;

lib/tests/run_tests.js

@@ -114,6 +114,7 @@ module.exports = {
 
           mocha.run(function (fails) {
             failures += fails;
+            mocha.suite.removeAllListeners();
             // Mocha prints the error already
             eachCb();
           });