From 2ada2681b48ad194bf0c8006ebb23d58bad4f473 Mon Sep 17 00:00:00 2001
From: Adam Raine <ad.st.raine@gmail.com>
Date: Wed, 19 Apr 2023 16:03:04 -0700
Subject: [PATCH 1/6] core: add metric savings to audit result

---
 core/audits/audit.js               |  1 +
 core/audits/third-party-summary.js |  3 +++
 types/audit.d.ts                   |  3 +++
 types/lhr/audit-result.d.ts        | 10 ++++++++++
 4 files changed, 17 insertions(+)

diff --git a/core/audits/audit.js b/core/audits/audit.js
index f44f617692af..4d3ca0d77c5e 100644
--- a/core/audits/audit.js
+++ b/core/audits/audit.js
@@ -410,6 +410,7 @@ class Audit {
       warnings: product.warnings,
 
       details: product.details,
+      metricSavings: product.metricSavings,
     };
   }
 }
diff --git a/core/audits/third-party-summary.js b/core/audits/third-party-summary.js
index a2e67df5e1e3..8b7756cfea70 100644
--- a/core/audits/third-party-summary.js
+++ b/core/audits/third-party-summary.js
@@ -252,6 +252,9 @@ class ThirdPartySummary extends Audit {
         timeInMs: overallSummary.wastedMs,
       }),
       details,
+      metricSavings: {
+        TBT: overallSummary.wastedMs,
+      },
     };
   }
 }
diff --git a/types/audit.d.ts b/types/audit.d.ts
index 25ecd139c345..a7c61930b432 100644
--- a/types/audit.d.ts
+++ b/types/audit.d.ts
@@ -18,6 +18,7 @@ declare module Audit {
   export type Result = AuditResult.Result;
   export type ScoreDisplayMode = AuditResult.ScoreDisplayMode;
   export type ScoreDisplayModes = AuditResult.ScoreDisplayModes;
+  export type MetricSavings = AuditResult.MetricSavings;
 
   type Context = Util.Immutable<{
     /** audit options */
@@ -81,6 +82,8 @@ declare module Audit {
     details?: AuditDetails;
     /** If an audit encounters unusual execution circumstances, strings can be put in this optional array to add top-level warnings to the LHR. */
     runWarnings?: Array<IcuMessage>;
+    /** Estimates of how much this audit affects various performance metrics. Values will be in the init of their respective metrics. */
+    metricSavings?: MetricSavings;
   }
 
   /** The Audit.Product type for audits that do not return a `numericValue`. */
diff --git a/types/lhr/audit-result.d.ts b/types/lhr/audit-result.d.ts
index b8285eca4bd9..2b6c9d0c96f4 100644
--- a/types/lhr/audit-result.d.ts
+++ b/types/lhr/audit-result.d.ts
@@ -24,6 +24,14 @@ interface ScoreDisplayModes {
 
 type ScoreDisplayMode = ScoreDisplayModes[keyof ScoreDisplayModes];
 
+interface MetricSavings {
+  LCP?: number;
+  FCP?: number;
+  CLS?: number;
+  TBT?: number;
+  INP?: number;
+}
+
 /** Audit result returned in Lighthouse report. All audits offer a description and score of 0-1. */
 export interface Result {
   displayValue?: string;
@@ -50,6 +58,8 @@ export interface Result {
   id: string;
   /** A more detailed description that describes why the audit is important and links to Lighthouse documentation on the audit; markdown links supported. */
   description: string;
+  /** Estimates of how much this audit affects various performance metrics. Values will be in the init of their respective metrics. */
+  metricSavings?: MetricSavings;
   /** A numeric value that has a meaning specific to the audit, e.g. the number of nodes in the DOM or the timestamp of a specific load event. More information can be found in the audit details, if present. */
   numericValue?: number;
   /** The unit of `numericValue`, used when the consumer wishes to convert numericValue to a display string. */

From 834e3e9377e8b6c08f27cdfe4d3f9f2a75a88ba3 Mon Sep 17 00:00:00 2001
From: Adam Raine <ad.st.raine@gmail.com>
Date: Wed, 19 Apr 2023 16:05:18 -0700
Subject: [PATCH 2/6] comments

---
 types/audit.d.ts            | 2 +-
 types/lhr/audit-result.d.ts | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/types/audit.d.ts b/types/audit.d.ts
index a7c61930b432..0fa3cbfdabf9 100644
--- a/types/audit.d.ts
+++ b/types/audit.d.ts
@@ -82,7 +82,7 @@ declare module Audit {
     details?: AuditDetails;
     /** If an audit encounters unusual execution circumstances, strings can be put in this optional array to add top-level warnings to the LHR. */
     runWarnings?: Array<IcuMessage>;
-    /** Estimates of how much this audit affects various performance metrics. Values will be in the init of their respective metrics. */
+    /** Estimates of how much this audit affects various performance metrics. Values will be in the unit of the respective metrics. */
     metricSavings?: MetricSavings;
   }
 
diff --git a/types/lhr/audit-result.d.ts b/types/lhr/audit-result.d.ts
index 2b6c9d0c96f4..0265b6e64f39 100644
--- a/types/lhr/audit-result.d.ts
+++ b/types/lhr/audit-result.d.ts
@@ -58,7 +58,7 @@ export interface Result {
   id: string;
   /** A more detailed description that describes why the audit is important and links to Lighthouse documentation on the audit; markdown links supported. */
   description: string;
-  /** Estimates of how much this audit affects various performance metrics. Values will be in the init of their respective metrics. */
+  /** Estimates of how much this audit affects various performance metrics. Values will be in the unit of the respective metrics. */
   metricSavings?: MetricSavings;
   /** A numeric value that has a meaning specific to the audit, e.g. the number of nodes in the DOM or the timestamp of a specific load event. More information can be found in the audit details, if present. */
   numericValue?: number;

From f824dd5160e473624bb67ea8b6d2e2f639f19667 Mon Sep 17 00:00:00 2001
From: Adam Raine <ad.st.raine@gmail.com>
Date: Thu, 20 Apr 2023 13:54:53 -0700
Subject: [PATCH 3/6] sample

---
 .../fraggle-rock/reports/sample-flow-result.json         | 9 +++++++++
 core/test/results/sample_v2.json                         | 3 +++
 2 files changed, 12 insertions(+)

diff --git a/core/test/fixtures/fraggle-rock/reports/sample-flow-result.json b/core/test/fixtures/fraggle-rock/reports/sample-flow-result.json
index 1cfa67510599..b15ae593a7df 100644
--- a/core/test/fixtures/fraggle-rock/reports/sample-flow-result.json
+++ b/core/test/fixtures/fraggle-rock/reports/sample-flow-result.json
@@ -1477,6 +1477,9 @@
                 "wastedMs": 0
               },
               "isEntityGrouped": true
+            },
+            "metricSavings": {
+              "TBT": 0
             }
           },
           "third-party-facades": {
@@ -8679,6 +8682,9 @@
                 "wastedMs": 0
               },
               "isEntityGrouped": true
+            },
+            "metricSavings": {
+              "TBT": 0
             }
           },
           "layout-shift-elements": {
@@ -17324,6 +17330,9 @@
                 }
               ],
               "isEntityGrouped": true
+            },
+            "metricSavings": {
+              "TBT": 0
             }
           },
           "third-party-facades": {
diff --git a/core/test/results/sample_v2.json b/core/test/results/sample_v2.json
index 14a5fa547071..6a16ecc58977 100644
--- a/core/test/results/sample_v2.json
+++ b/core/test/results/sample_v2.json
@@ -2236,6 +2236,9 @@
           "wastedMs": 0
         },
         "isEntityGrouped": true
+      },
+      "metricSavings": {
+        "TBT": 0
       }
     },
     "third-party-facades": {

From 0d840d495fc3897823b6dcf4a2f94200e96f1fe1 Mon Sep 17 00:00:00 2001
From: Adam Raine <ad.st.raine@gmail.com>
Date: Thu, 20 Apr 2023 15:18:26 -0700
Subject: [PATCH 4/6] response time

---
 core/audits/server-response-time.js           |  7 ++++++-
 core/audits/third-party-summary.js            |  3 ---
 .../reports/sample-flow-result.json           | 21 +++++++++----------
 core/test/results/sample_v2.json              |  7 ++++---
 4 files changed, 20 insertions(+), 18 deletions(-)

diff --git a/core/audits/server-response-time.js b/core/audits/server-response-time.js
index c0df87c657c1..41070d7fb755 100644
--- a/core/audits/server-response-time.js
+++ b/core/audits/server-response-time.js
@@ -70,10 +70,11 @@ class ServerResponseTime extends Audit {
       {key: 'responseTime', valueType: 'timespanMs', label: str_(i18n.UIStrings.columnTimeSpent)},
     ];
 
+    const overallSavingsMs = Math.max(responseTime - TARGET_MS, 0);
     const details = Audit.makeOpportunityDetails(
       headings,
       [{url: mainResource.url, responseTime}],
-      {overallSavingsMs: responseTime - TARGET_MS}
+      {overallSavingsMs}
     );
 
     return {
@@ -82,6 +83,10 @@ class ServerResponseTime extends Audit {
       score: Number(passed),
       displayValue,
       details,
+      metricSavings: {
+        FCP: overallSavingsMs,
+        LCP: overallSavingsMs,
+      },
     };
   }
 }
diff --git a/core/audits/third-party-summary.js b/core/audits/third-party-summary.js
index 8b7756cfea70..a2e67df5e1e3 100644
--- a/core/audits/third-party-summary.js
+++ b/core/audits/third-party-summary.js
@@ -252,9 +252,6 @@ class ThirdPartySummary extends Audit {
         timeInMs: overallSummary.wastedMs,
       }),
       details,
-      metricSavings: {
-        TBT: overallSummary.wastedMs,
-      },
     };
   }
 }
diff --git a/core/test/fixtures/fraggle-rock/reports/sample-flow-result.json b/core/test/fixtures/fraggle-rock/reports/sample-flow-result.json
index b15ae593a7df..8894aa71ecfe 100644
--- a/core/test/fixtures/fraggle-rock/reports/sample-flow-result.json
+++ b/core/test/fixtures/fraggle-rock/reports/sample-flow-result.json
@@ -233,7 +233,11 @@
                   "responseTime": 19.687999999999988
                 }
               ],
-              "overallSavingsMs": -80.31200000000001
+              "overallSavingsMs": 0
+            },
+            "metricSavings": {
+              "FCP": 0,
+              "LCP": 0
             }
           },
           "interactive": {
@@ -1477,9 +1481,6 @@
                 "wastedMs": 0
               },
               "isEntityGrouped": true
-            },
-            "metricSavings": {
-              "TBT": 0
             }
           },
           "third-party-facades": {
@@ -8682,9 +8683,6 @@
                 "wastedMs": 0
               },
               "isEntityGrouped": true
-            },
-            "metricSavings": {
-              "TBT": 0
             }
           },
           "layout-shift-elements": {
@@ -16135,7 +16133,11 @@
                   "responseTime": 10.263
                 }
               ],
-              "overallSavingsMs": -89.737
+              "overallSavingsMs": 0
+            },
+            "metricSavings": {
+              "FCP": 0,
+              "LCP": 0
             }
           },
           "interactive": {
@@ -17330,9 +17332,6 @@
                 }
               ],
               "isEntityGrouped": true
-            },
-            "metricSavings": {
-              "TBT": 0
             }
           },
           "third-party-facades": {
diff --git a/core/test/results/sample_v2.json b/core/test/results/sample_v2.json
index 6a16ecc58977..61cd8eea7f3f 100644
--- a/core/test/results/sample_v2.json
+++ b/core/test/results/sample_v2.json
@@ -337,6 +337,10 @@
           }
         ],
         "overallSavingsMs": 468.46799999999996
+      },
+      "metricSavings": {
+        "FCP": 468.46799999999996,
+        "LCP": 468.46799999999996
       }
     },
     "interactive": {
@@ -2236,9 +2240,6 @@
           "wastedMs": 0
         },
         "isEntityGrouped": true
-      },
-      "metricSavings": {
-        "TBT": 0
       }
     },
     "third-party-facades": {

From 2adefed68d07ec6011f70917b54896e7ac91900f Mon Sep 17 00:00:00 2001
From: Adam Raine <ad.st.raine@gmail.com>
Date: Wed, 26 Apr 2023 13:09:04 -0700
Subject: [PATCH 5/6] move to audit details

---
 core/audits/audit.js                |  1 -
 core/audits/server-response-time.js |  8 ++++----
 types/audit.d.ts                    |  3 ---
 types/lhr/audit-details.d.ts        | 10 ++++++++++
 types/lhr/audit-result.d.ts         | 10 +---------
 5 files changed, 15 insertions(+), 17 deletions(-)

diff --git a/core/audits/audit.js b/core/audits/audit.js
index 4d3ca0d77c5e..f44f617692af 100644
--- a/core/audits/audit.js
+++ b/core/audits/audit.js
@@ -410,7 +410,6 @@ class Audit {
       warnings: product.warnings,
 
       details: product.details,
-      metricSavings: product.metricSavings,
     };
   }
 }
diff --git a/core/audits/server-response-time.js b/core/audits/server-response-time.js
index 41070d7fb755..a80dde34fa51 100644
--- a/core/audits/server-response-time.js
+++ b/core/audits/server-response-time.js
@@ -76,6 +76,10 @@ class ServerResponseTime extends Audit {
       [{url: mainResource.url, responseTime}],
       {overallSavingsMs}
     );
+    details.metricSavings = {
+      FCP: overallSavingsMs,
+      LCP: overallSavingsMs,
+    };
 
     return {
       numericValue: responseTime,
@@ -83,10 +87,6 @@ class ServerResponseTime extends Audit {
       score: Number(passed),
       displayValue,
       details,
-      metricSavings: {
-        FCP: overallSavingsMs,
-        LCP: overallSavingsMs,
-      },
     };
   }
 }
diff --git a/types/audit.d.ts b/types/audit.d.ts
index 0fa3cbfdabf9..25ecd139c345 100644
--- a/types/audit.d.ts
+++ b/types/audit.d.ts
@@ -18,7 +18,6 @@ declare module Audit {
   export type Result = AuditResult.Result;
   export type ScoreDisplayMode = AuditResult.ScoreDisplayMode;
   export type ScoreDisplayModes = AuditResult.ScoreDisplayModes;
-  export type MetricSavings = AuditResult.MetricSavings;
 
   type Context = Util.Immutable<{
     /** audit options */
@@ -82,8 +81,6 @@ declare module Audit {
     details?: AuditDetails;
     /** If an audit encounters unusual execution circumstances, strings can be put in this optional array to add top-level warnings to the LHR. */
     runWarnings?: Array<IcuMessage>;
-    /** Estimates of how much this audit affects various performance metrics. Values will be in the unit of the respective metrics. */
-    metricSavings?: MetricSavings;
   }
 
   /** The Audit.Product type for audits that do not return a `numericValue`. */
diff --git a/types/lhr/audit-details.d.ts b/types/lhr/audit-details.d.ts
index 17611dcf9baf..fc054c6913cf 100644
--- a/types/lhr/audit-details.d.ts
+++ b/types/lhr/audit-details.d.ts
@@ -15,6 +15,8 @@ interface BaseDetails {
   overallSavingsBytes?: number;
   /** Additional information, usually used for including debug or meta information in the LHR */
   debugData?: Details.DebugData;
+  /** Estimates of how much this audit affects various performance metrics. Values will be in the unit of the respective metrics. */
+  metricSavings?: Details.MetricSavings;
 }
 
 type Details =
@@ -303,6 +305,14 @@ declare module Details {
     value: number,
     granularity?: number,
   }
+
+  interface MetricSavings {
+    LCP?: number;
+    FCP?: number;
+    CLS?: number;
+    TBT?: number;
+    INP?: number;
+  }
 }
 
 export default Details;
diff --git a/types/lhr/audit-result.d.ts b/types/lhr/audit-result.d.ts
index 0265b6e64f39..48b3146740e4 100644
--- a/types/lhr/audit-result.d.ts
+++ b/types/lhr/audit-result.d.ts
@@ -24,14 +24,6 @@ interface ScoreDisplayModes {
 
 type ScoreDisplayMode = ScoreDisplayModes[keyof ScoreDisplayModes];
 
-interface MetricSavings {
-  LCP?: number;
-  FCP?: number;
-  CLS?: number;
-  TBT?: number;
-  INP?: number;
-}
-
 /** Audit result returned in Lighthouse report. All audits offer a description and score of 0-1. */
 export interface Result {
   displayValue?: string;
@@ -59,7 +51,7 @@ export interface Result {
   /** A more detailed description that describes why the audit is important and links to Lighthouse documentation on the audit; markdown links supported. */
   description: string;
   /** Estimates of how much this audit affects various performance metrics. Values will be in the unit of the respective metrics. */
-  metricSavings?: MetricSavings;
+  metricSavings?: AuditDetails.MetricSavings;
   /** A numeric value that has a meaning specific to the audit, e.g. the number of nodes in the DOM or the timestamp of a specific load event. More information can be found in the audit details, if present. */
   numericValue?: number;
   /** The unit of `numericValue`, used when the consumer wishes to convert numericValue to a display string. */

From d33636f62f5d3c727c57f2f2a5bef704d8c35506 Mon Sep 17 00:00:00 2001
From: Adam Raine <ad.st.raine@gmail.com>
Date: Wed, 26 Apr 2023 13:10:25 -0700
Subject: [PATCH 6/6] sample

---
 .../reports/sample-flow-result.json           | 20 +++++++++----------
 core/test/results/sample_v2.json              | 10 +++++-----
 2 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/core/test/fixtures/fraggle-rock/reports/sample-flow-result.json b/core/test/fixtures/fraggle-rock/reports/sample-flow-result.json
index 8894aa71ecfe..a066dcea3f0b 100644
--- a/core/test/fixtures/fraggle-rock/reports/sample-flow-result.json
+++ b/core/test/fixtures/fraggle-rock/reports/sample-flow-result.json
@@ -233,11 +233,11 @@
                   "responseTime": 19.687999999999988
                 }
               ],
-              "overallSavingsMs": 0
-            },
-            "metricSavings": {
-              "FCP": 0,
-              "LCP": 0
+              "overallSavingsMs": 0,
+              "metricSavings": {
+                "FCP": 0,
+                "LCP": 0
+              }
             }
           },
           "interactive": {
@@ -16133,11 +16133,11 @@
                   "responseTime": 10.263
                 }
               ],
-              "overallSavingsMs": 0
-            },
-            "metricSavings": {
-              "FCP": 0,
-              "LCP": 0
+              "overallSavingsMs": 0,
+              "metricSavings": {
+                "FCP": 0,
+                "LCP": 0
+              }
             }
           },
           "interactive": {
diff --git a/core/test/results/sample_v2.json b/core/test/results/sample_v2.json
index 61cd8eea7f3f..abc2b28a250d 100644
--- a/core/test/results/sample_v2.json
+++ b/core/test/results/sample_v2.json
@@ -336,11 +336,11 @@
             "responseTime": 568.468
           }
         ],
-        "overallSavingsMs": 468.46799999999996
-      },
-      "metricSavings": {
-        "FCP": 468.46799999999996,
-        "LCP": 468.46799999999996
+        "overallSavingsMs": 468.46799999999996,
+        "metricSavings": {
+          "FCP": 468.46799999999996,
+          "LCP": 468.46799999999996
+        }
       }
     },
     "interactive": {