From eb05a569d09796e79e2e8565fa71c0543b5674d1 Mon Sep 17 00:00:00 2001
From: Davis Plumlee <56367316+dplumlee@users.noreply.github.com>
Date: Wed, 21 Oct 2020 21:03:38 -0600
Subject: [PATCH] [Security Solution][Detections] Look-back time logic fix
 (#81383) (#81426)

---
 .../detection_engine/rules/helpers.test.tsx   | 24 ++++++++++++++-----
 .../pages/detection_engine/rules/helpers.tsx  | 18 +++++++++-----
 2 files changed, 30 insertions(+), 12 deletions(-)

diff --git a/x-pack/plugins/security_solution/public/detections/pages/detection_engine/rules/helpers.test.tsx b/x-pack/plugins/security_solution/public/detections/pages/detection_engine/rules/helpers.test.tsx
index 0cd75506fa9f50..a327f8498f7c0b 100644
--- a/x-pack/plugins/security_solution/public/detections/pages/detection_engine/rules/helpers.test.tsx
+++ b/x-pack/plugins/security_solution/public/detections/pages/detection_engine/rules/helpers.test.tsx
@@ -300,28 +300,40 @@ describe('rule helpers', () => {
   });
 
   describe('getHumanizedDuration', () => {
-    test('returns from as seconds if from duration is less than a minute', () => {
+    test('returns from as seconds if from duration is specified in seconds', () => {
       const result = getHumanizedDuration('now-62s', '1m');
 
       expect(result).toEqual('2s');
     });
 
-    test('returns from as minutes if from duration is less than an hour', () => {
+    test('returns from as seconds if from duration is specified in seconds greater than 60', () => {
+      const result = getHumanizedDuration('now-122s', '1m');
+
+      expect(result).toEqual('62s');
+    });
+
+    test('returns from as minutes if from duration is specified in minutes', () => {
       const result = getHumanizedDuration('now-660s', '5m');
 
       expect(result).toEqual('6m');
     });
 
-    test('returns from as hours if from duration is more than 60 minutes', () => {
-      const result = getHumanizedDuration('now-7400s', '5m');
+    test('returns from as minutes if from duration is specified in minutes greater than 60', () => {
+      const result = getHumanizedDuration('now-6600s', '5m');
+
+      expect(result).toEqual('105m');
+    });
+
+    test('returns from as hours if from duration is specified in hours', () => {
+      const result = getHumanizedDuration('now-7500s', '5m');
 
-      expect(result).toEqual('1h');
+      expect(result).toEqual('2h');
     });
 
     test('returns from as if from is not parsable as dateMath', () => {
       const result = getHumanizedDuration('randomstring', '5m');
 
-      expect(result).toEqual('NaNh');
+      expect(result).toEqual('NaNs');
     });
 
     test('returns from as 5m if interval is not parsable as dateMath', () => {
diff --git a/x-pack/plugins/security_solution/public/detections/pages/detection_engine/rules/helpers.tsx b/x-pack/plugins/security_solution/public/detections/pages/detection_engine/rules/helpers.tsx
index 4dbcffbc807ec1..ffcf25d2537985 100644
--- a/x-pack/plugins/security_solution/public/detections/pages/detection_engine/rules/helpers.tsx
+++ b/x-pack/plugins/security_solution/public/detections/pages/detection_engine/rules/helpers.tsx
@@ -118,15 +118,21 @@ export const getHumanizedDuration = (from: string, interval: string): string =>
   const intervalValue = dateMath.parse(`now-${interval}`) ?? moment();
 
   const fromDuration = moment.duration(intervalValue.diff(fromValue));
-  const fromHumanize = `${Math.floor(fromDuration.asHours())}h`;
 
-  if (fromDuration.asSeconds() < 60) {
-    return `${Math.floor(fromDuration.asSeconds())}s`;
-  } else if (fromDuration.asMinutes() < 60) {
-    return `${Math.floor(fromDuration.asMinutes())}m`;
+  // Basing calculations off floored seconds count as moment durations weren't precise
+  const intervalDuration = Math.floor(fromDuration.asSeconds());
+  // For consistency of display value
+  if (intervalDuration === 0) {
+    return `0s`;
   }
 
-  return fromHumanize;
+  if (intervalDuration % 3600 === 0) {
+    return `${intervalDuration / 3600}h`;
+  } else if (intervalDuration % 60 === 0) {
+    return `${intervalDuration / 60}m`;
+  } else {
+    return `${intervalDuration}s`;
+  }
 };
 
 export const getAboutStepsData = (rule: Rule, detailsView: boolean): AboutStepRule => {