From 92e6fbb9b2a5df2ee6ddac998b8a784b014c3c87 Mon Sep 17 00:00:00 2001
From: Trevor Burnham <trevor.burnham@compass.com>
Date: Sun, 5 Dec 2021 14:11:43 -0500
Subject: [PATCH] fix(storybook): Use parameters from first story in group

Fixes #15772

The previous behavior was to use the parameters from the last story in the group.
---
 lib/api/src/lib/stories.ts        |  3 +++
 lib/api/src/tests/stories.test.js | 11 +++++++----
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/lib/api/src/lib/stories.ts b/lib/api/src/lib/stories.ts
index 044b728ca04e..36901a5d816f 100644
--- a/lib/api/src/lib/stories.ts
+++ b/lib/api/src/lib/stories.ts
@@ -267,9 +267,12 @@ export const transformStoriesRawToStoriesHash = (
     rootAndGroups.forEach((group, index) => {
       const child = paths[index + 1];
       const { id } = group;
+      // @ts-ignore
+      const { parameters: originalParameters = group.parameters } = acc[id] || {};
       acc[id] = merge(acc[id] || {}, {
         ...group,
         ...(child && { children: [child] }),
+        parameters: originalParameters,
       });
     });
 
diff --git a/lib/api/src/tests/stories.test.js b/lib/api/src/tests/stories.test.js
index 8cf027d5f317..18e406ebcd51 100644
--- a/lib/api/src/tests/stories.test.js
+++ b/lib/api/src/tests/stories.test.js
@@ -83,6 +83,8 @@ describe('stories API', () => {
     });
   });
   const parameters = {};
+  const firstInGroupParameters = { viewMode: 'docs' };
+  const secondInGroupParameters = { viewMode: 'story' };
   const storiesHash = {
     'a--1': { kind: 'a', name: '1', parameters, path: 'a--1', id: 'a--1', args: {} },
     'a--2': { kind: 'a', name: '2', parameters, path: 'a--2', id: 'a--2', args: {} },
@@ -97,7 +99,7 @@ describe('stories API', () => {
     'b-d--1': {
       kind: 'b/d',
       name: '1',
-      parameters,
+      parameters: firstInGroupParameters,
       path: 'b-d--1',
       id: 'b-d--1',
       args: {},
@@ -105,7 +107,7 @@ describe('stories API', () => {
     'b-d--2': {
       kind: 'b/d',
       name: '2',
-      parameters,
+      parameters: secondInGroupParameters,
       path: 'b-d--2',
       id: 'b-d--2',
       args: { a: 'b' },
@@ -207,6 +209,7 @@ describe('stories API', () => {
         id: 'b-d',
         parent: 'b',
         children: ['b-d--1', 'b-d--2'],
+        parameters: firstInGroupParameters,
         isRoot: false,
         isComponent: true,
       });
@@ -216,7 +219,7 @@ describe('stories API', () => {
         parent: 'b-d',
         kind: 'b/d',
         name: '1',
-        parameters,
+        parameters: firstInGroupParameters,
         args: {},
         prepared: true,
       });
@@ -226,7 +229,7 @@ describe('stories API', () => {
         parent: 'b-d',
         kind: 'b/d',
         name: '2',
-        parameters,
+        parameters: secondInGroupParameters,
         args: { a: 'b' },
         prepared: true,
       });