From 4f2f577f5fec69bd26db79e693ade91d92c7c0b5 Mon Sep 17 00:00:00 2001
From: Jeremy Press <jpress@box.com>
Date: Mon, 23 Apr 2018 13:21:39 -0700
Subject: [PATCH] Chore: Refactor Timer to allow a reset of multiple tags
 (#778)

---
 src/lib/Preview.js                | 15 +++++++--------
 src/lib/Timer.js                  | 20 ++++++++++++--------
 src/lib/__tests__/Preview-test.js |  4 ++--
 src/lib/__tests__/Timer-test.js   | 22 ++++++++++++++++++++++
 4 files changed, 43 insertions(+), 18 deletions(-)

diff --git a/src/lib/Preview.js b/src/lib/Preview.js
index 56e0ec236..2f2a84ded 100644
--- a/src/lib/Preview.js
+++ b/src/lib/Preview.js
@@ -1474,22 +1474,21 @@ class Preview extends EventEmitter {
      */
     emitLoadMetrics() {
         if (!this.file || !this.file.id) {
-            Timer.reset();
             return;
         }
 
-        // Do nothing if there is nothing worth logging.
         const infoTag = Timer.createTag(this.file.id, LOAD_METRIC.fileInfoTime);
+        const convertTag = Timer.createTag(this.file.id, LOAD_METRIC.convertTime);
+        const downloadTag = Timer.createTag(this.file.id, LOAD_METRIC.downloadResponseTime);
+        const fullLoadTag = Timer.createTag(this.file.id, LOAD_METRIC.fullDocumentLoadTime);
+
+        // Do nothing if there is nothing worth logging.
         const infoTime = Timer.get(infoTag) || {};
         if (!infoTime.elapsed) {
-            Timer.reset();
+            Timer.reset([infoTag, convertTag, downloadTag, fullLoadTag]);
             return;
         }
 
-        const convertTag = Timer.createTag(this.file.id, LOAD_METRIC.convertTime);
-        const downloadTag = Timer.createTag(this.file.id, LOAD_METRIC.downloadResponseTime);
-        const fullLoadTag = Timer.createTag(this.file.id, LOAD_METRIC.fullDocumentLoadTime);
-
         const timerList = [
             infoTime,
             Timer.get(convertTag) || {},
@@ -1511,7 +1510,7 @@ class Preview extends EventEmitter {
 
         this.emit(PREVIEW_METRIC, event);
 
-        Timer.reset();
+        Timer.reset([infoTag, convertTag, downloadTag, fullLoadTag]);
     }
 
     /**
diff --git a/src/lib/Timer.js b/src/lib/Timer.js
index ac8362499..e15006752 100644
--- a/src/lib/Timer.js
+++ b/src/lib/Timer.js
@@ -63,14 +63,20 @@ class Timer {
      * Resets the values in a certain time structure, if it exists.
      *
      * @public
-     * @param {string} [tag] - If provided, will reset a specific time structure associated with the tag.
-     *                         If empty, resets everything.
+     * @param {string|string[]} [tagOrTags] - If provided, will reset a specific time structure associated with
+     * the tag or array of tags. If empty, resets all tags.
+     *
      * @return {void}
      */
-    reset(tag) {
-        if (tag) {
-            const time = this.get(tag);
+    reset(tagOrTags) {
+        if (!tagOrTags) {
+            Object.keys(this.times).forEach(this.reset.bind(this));
+            return;
+        }
 
+        const tagArray = typeof tagOrTags === 'string' ? [tagOrTags] : tagOrTags;
+        tagArray.forEach((tag) => {
+            const time = this.get(tag);
             // If nothing exists, there's no reason to reset it
             if (!time) {
                 return;
@@ -79,9 +85,7 @@ class Timer {
             time.start = undefined;
             time.end = undefined;
             time.elapsed = undefined;
-        } else {
-            Object.keys(this.times).forEach(this.reset.bind(this));
-        }
+        });
     }
 
     /**
diff --git a/src/lib/__tests__/Preview-test.js b/src/lib/__tests__/Preview-test.js
index 280f1e276..0efdd6164 100644
--- a/src/lib/__tests__/Preview-test.js
+++ b/src/lib/__tests__/Preview-test.js
@@ -2222,12 +2222,12 @@ describe('lib/Preview', () => {
             Timer.reset();
         });
 
-        it('should reset the Timer and escape early if no file or file id', () => {
+        it('should do nothingescape early if no file or file id', () => {
             sandbox.stub(Timer, 'reset');
             sandbox.stub(preview, 'emit');
             preview.file = undefined;
             preview.emitLoadMetrics();
-            expect(Timer.reset).to.be.called;
+            expect(Timer.reset).to.not.be.called;
             expect(preview.emit).to.not.be.called;
         });
 
diff --git a/src/lib/__tests__/Timer-test.js b/src/lib/__tests__/Timer-test.js
index 943f1b257..929c97818 100644
--- a/src/lib/__tests__/Timer-test.js
+++ b/src/lib/__tests__/Timer-test.js
@@ -118,6 +118,28 @@ describe('lib/Timer', () => {
             expect(Timer.get(other).end).to.not.exist;
             expect(Timer.get(other).elapsed).to.not.exist;
         });
+
+        it('should reset multiple tags given an array of tags', () => {
+            Timer.start(tag);
+            Timer.stop(tag);
+            const other = 'other_tag';
+            Timer.start(other);
+            Timer.stop(other);
+            const another = 'another_tag';
+            Timer.start(another);
+            Timer.stop(another);
+            Timer.reset([tag, other]);
+
+            expect(Timer.get(tag).start).to.not.exist;
+            expect(Timer.get(tag).end).to.not.exist;
+            expect(Timer.get(tag).elapsed).to.not.exist;
+            expect(Timer.get(other).start).to.not.exist;
+            expect(Timer.get(other).end).to.not.exist;
+            expect(Timer.get(other).elapsed).to.not.exist;
+            expect(Timer.get(another).start).to.exist;
+            expect(Timer.get(another).end).to.exist;
+            expect(Timer.get(another).elapsed).to.exist;
+        });
     });
 
     describe('createTag()', () => {