Improves support for long build traces:

3 files changed, 30 insertions, 8 deletions

diff --git a/app/assets/javascripts/build.js b/app/assets/javascripts/build.js
index 0aad95c2fe3..97f279e4be4 100644
--- a/app/assets/javascripts/build.js
+++ b/app/assets/javascripts/build.js
@@ -2,6 +2,8 @@
 consistent-return, prefer-rest-params */
 /* global Breakpoints */
 
+import { bytesToKiB } from './lib/utils/number_utils';
+
 const bind = function (fn, me) { return function () { return fn.apply(me, arguments); }; };
 const AUTO_SCROLL_OFFSET = 75;
 const DOWN_BUILD_TRACE = '#down-build-trace';
@@ -20,6 +22,7 @@ window.Build = (function () {
     this.state = this.options.logState;
     this.buildStage = this.options.buildStage;
     this.$document = $(document);
+    this.logBytes = 0;
 
     this.updateDropdown = bind(this.updateDropdown, this);
 
@@ -98,15 +101,22 @@ window.Build = (function () {
 
         if (log.append) {
           $buildContainer.append(log.html);
+          this.logBytes += log.size;
         } else {
           $buildContainer.html(log.html);
-          if (log.truncated) {
-            $('.js-truncated-info-size').html(` ${log.size} `);
-            this.$truncatedInfo.removeClass('hidden');
-            this.initAffixTruncatedInfo();
-          } else {
-            this.$truncatedInfo.addClass('hidden');
-          }
+          this.logBytes = log.size;
+        }
+
+        // if the incremental sum of logBytes we received is less than the total
+        // we need to show a message warning the user about that.
+        if (this.logBytes < log.total) {
+          // size is in bytes, we need to calculate KiB
+          const size = bytesToKiB(this.logBytes);
+          $('.js-truncated-info-size').html(`${size}`);
+          this.$truncatedInfo.removeClass('hidden');
+          this.initAffixTruncatedInfo();
+        } else {
+          this.$truncatedInfo.addClass('hidden');
         }
 
         this.checkAutoscroll();
diff --git a/app/assets/javascripts/lib/utils/constants.js b/app/assets/javascripts/lib/utils/constants.js
new file mode 100644
index 00000000000..1e96c7ab5cd
--- /dev/null
+++ b/app/assets/javascripts/lib/utils/constants.js
@@ -0,0 +1,2 @@
+/* eslint-disable import/prefer-default-export */
+export const BYTES_IN_KIB = 1024;
diff --git a/app/assets/javascripts/lib/utils/number_utils.js b/app/assets/javascripts/lib/utils/number_utils.js
index e2bf69ee52e..f1b07408671 100644
--- a/app/assets/javascripts/lib/utils/number_utils.js
+++ b/app/assets/javascripts/lib/utils/number_utils.js
@@ -1,4 +1,4 @@
-/* eslint-disable import/prefer-default-export */
+import { BYTES_IN_KIB } from './constants';
 
 /**
  * Function that allows a number with an X amount of decimals
@@ -32,3 +32,13 @@ export function formatRelevantDigits(number) {
   }
   return formattedNumber;
 }
+
+/**
+ * Utility function that calculates KiB of the given bytes.
+ *
+ * @param  {Number} number bytes
+ * @return {Number}        KiB
+ */
+export function bytesToKiB(number) {
+  return number / BYTES_IN_KIB;
+}