feat: add option sideNavLayout

Add support for theme option `sideNavLayout`.  If set to `factored`,
the side-nav menu will group items that share a common path prefix.

For example, if the default layout for side-nav looked like this:

	/config        >
        /config/alert  >
        /config/bacnet >
        /config/modbus >
        /log           >

Then the factored side-nav would look like this:

	/config        >
        /log           >

and after expanding /config, you'd see:

	/config        v
          GET /config
          PUT /config
          …/alert      >
          …/bacnet     >
          …/modbus     >
        /log           >

Note that this commit also updates the styling to show a vertical line
to the left of all side-bar <ul> lists that are not at the root level.
This probably should be configurable.

src/components/SideMenu/MenuItems.tsx

@@ -26,6 +26,7 @@ export class MenuItems extends React.Component<MenuItemsProps> {
         className={className}
         style={this.props.style}
         $expanded={expanded}
+        root={root || false}
         {...(root ? { role: 'menu' } : {})}
       >
         {items.map((item, idx) => (

src/components/SideMenu/styled.elements.ts

@@ -84,7 +84,7 @@ function menuItemActive(
   }
 }
 
-export const MenuItemUl = styled.ul<{ $expanded: boolean }>`
+export const MenuItemUl = styled.ul<{ $expanded: boolean; root: boolean }>`
   margin: 0;
   padding: 0;
 
@@ -97,6 +97,8 @@ export const MenuItemUl = styled.ul<{ $expanded: boolean }>`
   }
 
   ${props => (props.$expanded ? '' : 'display: none;')};
+  ${props => (props.root ? '' : 'margin-left: 8px;')};
+  ${props => (props.root ? '' : 'border-left: 1px solid lightblue;')}
 `;
 
 export const MenuItemLi = styled.li<{ depth: number }>`

src/services/MenuBuilder.ts

@@ -28,7 +28,41 @@ export class MenuBuilder {
     } else {
       items.push(...MenuBuilder.getTagsItems(parser, tagsMap, undefined, undefined, options));
     }
-    return items;
+
+    if (options.sideNavLayout !== 'factored') return items;
+
+    return MenuBuilder.factorByPrefix(items);
+  }
+
+  static factorByPrefix(items: ContentItemModel[]): ContentItemModel[] {
+    const newItems: ContentItemModel[] = [];
+    let newChildren: ContentItemModel[] = [];
+    let parent: GroupModel | null = null;
+    let prefix = '';
+    for (const item of items) {
+      if (parent && item.name.startsWith(prefix)) {
+        item.parent = parent;
+        item.depth = parent.depth + 1;
+        newChildren.push(item);
+      } else {
+        if (newChildren.length > 0) {
+          for (const child of MenuBuilder.factorByPrefix(newChildren)) {
+            if (child.sidebarLabel.startsWith(prefix)) {
+              child.sidebarLabel = '…' + child.sidebarLabel.slice(prefix.length - 1);
+            }
+            parent!.items.push(child);
+          }
+          newChildren = [];
+        }
+
+        newItems.push(item);
+        if (item instanceof GroupModel) {
+          parent = item;
+          prefix = item.name + '/';
+        } else parent = null;
+      }
+    }
+    return newItems;
   }
 
   /**

src/services/RedocNormalizedOptions.ts

@@ -27,6 +27,7 @@ export interface RedocRawOptions {
   onlyRequiredInSamples?: boolean | string;
   showExtensions?: boolean | string | string[];
   sideNavStyle?: SideNavStyleEnum;
+  sideNavLayout?: 'default' | 'factored';
   hideSingleRequestSampleTab?: boolean | string;
   hideRequestPayloadSample?: boolean;
   menuToggle?: boolean | string;
@@ -180,6 +181,10 @@ export class RedocNormalizedOptions {
     }
   }
 
+  static normalizeSideNavLayout(value: RedocRawOptions['sideNavLayout']): 'default' | 'factored' {
+    return value === 'factored' ? value : 'default';
+  }
+
   static normalizePayloadSampleIdx(value: RedocRawOptions['payloadSampleIdx']): number {
     if (typeof value === 'number') {
       return Math.max(0, value); // always greater or equal than 0
@@ -231,6 +236,7 @@ export class RedocNormalizedOptions {
   onlyRequiredInSamples: boolean;
   showExtensions: boolean | string[];
   sideNavStyle: SideNavStyleEnum;
+  sideNavLayout: 'default' | 'factored';
   hideSingleRequestSampleTab: boolean;
   hideRequestPayloadSample: boolean;
   menuToggle: boolean;
@@ -303,6 +309,7 @@ export class RedocNormalizedOptions {
     this.onlyRequiredInSamples = argValueToBoolean(raw.onlyRequiredInSamples);
     this.showExtensions = RedocNormalizedOptions.normalizeShowExtensions(raw.showExtensions);
     this.sideNavStyle = RedocNormalizedOptions.normalizeSideNavStyle(raw.sideNavStyle);
+    this.sideNavLayout = RedocNormalizedOptions.normalizeSideNavLayout(raw.sideNavLayout);
     this.hideSingleRequestSampleTab = argValueToBoolean(raw.hideSingleRequestSampleTab);
     this.hideRequestPayloadSample = argValueToBoolean(raw.hideRequestPayloadSample);
     this.menuToggle = argValueToBoolean(raw.menuToggle, true);