fix(folders): Use real folder names instead of splicing slugs

In breadcrumbs and folder pages (both folder page titles and page
lists) the name of the folder was derived from the slug unless
overriden, which is.. wonky.

This is much more noticeable if you change the slugify function to make
all slugs lowercase - which I did, and which may be a followup PR.

The patch was pretty straightforward though, we just use the real
folder names from the relativePath.

quartz/components/Breadcrumbs.tsx

@@ -40,11 +40,8 @@ const defaultOptions: BreadcrumbOptions = {
   showCurrentPage: true,
 }
 
-function formatCrumb(displayName: string, baseSlug: FullSlug, currentSlug: SimpleSlug): CrumbData {
-  return {
-    displayName: displayName.replaceAll("-", " "),
-    path: resolveRelative(baseSlug, currentSlug),
-  }
+function newCrumb(displayName: string, baseSlug: FullSlug, currentSlug: SimpleSlug): CrumbData {
+  return { displayName, path: resolveRelative(baseSlug, currentSlug) }
 }
 
 export default ((opts?: Partial<BreadcrumbOptions>) => {
@@ -65,7 +62,7 @@ export default ((opts?: Partial<BreadcrumbOptions>) => {
     }
 
     // Format entry for root element
-    const firstEntry = formatCrumb(options.rootName, fileData.slug!, "/" as SimpleSlug)
+    const firstEntry = newCrumb(options.rootName, fileData.slug!, "/" as SimpleSlug)
     const crumbs: CrumbData[] = [firstEntry]
 
     if (!folderIndex && options.resolveFrontmatterTitle) {
@@ -81,6 +78,7 @@ export default ((opts?: Partial<BreadcrumbOptions>) => {
 
     // Split slug into hierarchy/parts
     const slugParts = fileData.slug?.split("/")
+    const pathParts = fileData.relativePath?.split("/")
     if (slugParts) {
       // is tag breadcrumb?
       const isTagPath = slugParts[0] === "tags"
@@ -89,7 +87,7 @@ export default ((opts?: Partial<BreadcrumbOptions>) => {
       let currentPath = ""
 
       for (let i = 0; i < slugParts.length - 1; i++) {
-        let curPathSegment = slugParts[i]
+        let curPathSegment = pathParts?.[i] ?? slugParts[i]
 
         // Try to resolve frontmatter folder title
         const currentFile = folderIndex?.get(slugParts.slice(0, i + 1).join("/"))
@@ -105,7 +103,7 @@ export default ((opts?: Partial<BreadcrumbOptions>) => {
         const includeTrailingSlash = !isTagPath || i < 1
 
         // Format and add current crumb
-        const crumb = formatCrumb(
+        const crumb = newCrumb(
           curPathSegment,
           fileData.slug!,
           (currentPath + (includeTrailingSlash ? "/" : "")) as SimpleSlug,

quartz/components/pages/FolderContent.tsx

@@ -23,6 +23,11 @@ const defaultOptions: FolderContentOptions = {
   showSubfolders: true,
 }
 
+type Subfolder = {
+  name: string
+  contents: QuartzPluginData[]
+}
+
 export default ((opts?: Partial<FolderContentOptions>) => {
   const options: FolderContentOptions = { ...defaultOptions, ...opts }
 
@@ -31,51 +36,56 @@ export default ((opts?: Partial<FolderContentOptions>) => {
     const folderSlug = stripSlashes(simplifySlug(fileData.slug!))
     const folderParts = folderSlug.split(path.posix.sep)
 
-    const allPagesInFolder: QuartzPluginData[] = []
-    const allPagesInSubfolders: Map<FullSlug, QuartzPluginData[]> = new Map()
+    const shownPages: QuartzPluginData[] = []
+    const subfolders: Map<FullSlug, Subfolder> = new Map()
 
-    allFiles.forEach((file) => {
+    for (const file of allFiles) {
       const fileSlug = stripSlashes(simplifySlug(file.slug!))
-      const prefixed = fileSlug.startsWith(folderSlug) && fileSlug !== folderSlug
-      const fileParts = fileSlug.split(path.posix.sep)
-      const isDirectChild = fileParts.length === folderParts.length + 1
-
-      if (!prefixed) {
-        return
+      // check only files in our folder or nested folders
+      if (!fileSlug.startsWith(folderSlug) || fileSlug === folderSlug) {
+        continue
       }
 
-      if (isDirectChild) {
-        allPagesInFolder.push(file)
-      } else if (options.showSubfolders) {
+      const fileParts = fileSlug.split(path.posix.sep)
+
+      // If the file is directly in the folder we just show it
+      if (fileParts.length === folderParts.length + 1) {
+        shownPages.push(file)
+        continue
+      }
+
+      if (options.showSubfolders) {
         const subfolderSlug = joinSegments(
           ...fileParts.slice(0, folderParts.length + 1),
         ) as FullSlug
-        const pagesInFolder = allPagesInSubfolders.get(subfolderSlug) || []
-        allPagesInSubfolders.set(subfolderSlug, [...pagesInFolder, file])
-      }
-    })
 
-    allPagesInSubfolders.forEach((files, subfolderSlug) => {
-      const hasIndex = allPagesInFolder.some(
-        (file) => subfolderSlug === stripSlashes(simplifySlug(file.slug!)),
-      )
+        let subfolder = subfolders.get(subfolderSlug)
+        if (!subfolder) {
+          const subfolderName = file.relativePath!.split(path.posix.sep).at(folderParts.length)!
+          subfolders.set(subfolderSlug, (subfolder = { name: subfolderName, contents: [] }))
+        }
+        subfolder.contents.push(file)
+      }
+    }
+
+    for (const [slug, subfolder] of subfolders.entries()) {
+      const hasIndex = shownPages.some((file) => slug === stripSlashes(simplifySlug(file.slug!)))
       if (!hasIndex) {
-        const subfolderDates = files.sort(byDateAndAlphabetical(cfg))[0].dates
-        const subfolderTitle = subfolderSlug.split(path.posix.sep).at(-1)!
-        allPagesInFolder.push({
-          slug: subfolderSlug,
+        const subfolderDates = subfolder.contents.sort(byDateAndAlphabetical(cfg))[0].dates
+        shownPages.push({
+          slug: slug,
           dates: subfolderDates,
-          frontmatter: { title: subfolderTitle, tags: ["folder"] },
+          frontmatter: { title: subfolder.name, tags: ["folder"] },
         })
       }
-    })
+    }
 
     const cssClasses: string[] = fileData.frontmatter?.cssclasses ?? []
     const classes = cssClasses.join(" ")
     const listProps = {
       ...props,
       sort: options.sort,
-      allFiles: allPagesInFolder,
+      allFiles: shownPages,
     }
 
     const content =
@@ -90,7 +100,7 @@ export default ((opts?: Partial<FolderContentOptions>) => {
           {options.showFolderCount && (
             <p>
               {i18n(cfg.locale).pages.folderContent.itemsUnderFolder({
-                count: allPagesInFolder.length,
+                count: shownPages.length,
               })}
             </p>
           )}

quartz/plugins/emitters/folderPage.tsx

@@ -74,13 +74,27 @@ export const FolderPage: QuartzEmitterPlugin<Partial<FolderPageOptions>> = (user
       const allFiles = content.map((c) => c[1].data)
       const cfg = ctx.cfg.configuration
 
+      const folderNames: Record<SimpleSlug, string> = {}
+
       const folders: Set<SimpleSlug> = new Set(
         allFiles.flatMap((data) => {
-          return data.slug
-            ? _getFolders(data.slug).filter(
-                (folderName) => folderName !== "." && folderName !== "tags",
-              )
-            : []
+          if (!data.slug || !data.relativePath) {
+            return []
+          }
+          let folderSlug = path.dirname(data.slug) as SimpleSlug
+          let folderFs = path.dirname(data.relativePath) as SimpleSlug
+          folderNames[folderSlug] = folderFs
+
+          const folders = [folderSlug]
+          while (folderSlug !== ".") {
+            folderSlug = path.dirname(folderSlug) as SimpleSlug
+            folders.push(folderSlug)
+
+            folderFs = path.dirname(folderFs) as SimpleSlug
+            folderNames[folderSlug] = folderFs
+          }
+
+          return folders.filter((f) => f !== "." && f !== "tags")
         }),
       )
 
@@ -89,8 +103,9 @@ export const FolderPage: QuartzEmitterPlugin<Partial<FolderPageOptions>> = (user
           folder,
           defaultProcessedContent({
             slug: joinSegments(folder, "index") as FullSlug,
+            relativePath: joinSegments(folderNames[folder], "index.html") as FilePath, // this is used by breadcrumbs
             frontmatter: {
-              title: `${i18n(cfg.locale).pages.folderContent.folder}: ${folder}`,
+              title: `${i18n(cfg.locale).pages.folderContent.folder}: ${folderNames[folder]}`,
               tags: [],
             },
           }),
@@ -100,7 +115,14 @@ export const FolderPage: QuartzEmitterPlugin<Partial<FolderPageOptions>> = (user
       for (const [tree, file] of content) {
         const slug = stripSlashes(simplifySlug(file.data.slug!)) as SimpleSlug
         if (folders.has(slug)) {
-          folderDescriptions[slug] = [tree, file]
+          if (file.data.frontmatter?.title === "index") {
+            // sadly we need to avoid changing the original file title for things like explorer to work
+            const clonedFile = structuredClone(file)
+            clonedFile.data.frontmatter!.title = `${i18n(cfg.locale).pages.folderContent.folder}: ${folderNames[slug]}`
+            folderDescriptions[slug] = [tree, clonedFile]
+          } else {
+            folderDescriptions[slug] = [tree, file]
+          }
         }
       }
 
@@ -132,14 +154,3 @@ export const FolderPage: QuartzEmitterPlugin<Partial<FolderPageOptions>> = (user
     },
   }
 }
-
-function _getFolders(slug: FullSlug): SimpleSlug[] {
-  var folderName = path.dirname(slug ?? "") as SimpleSlug
-  const parentFolderNames = [folderName]
-
-  while (folderName !== ".") {
-    folderName = path.dirname(folderName ?? "") as SimpleSlug
-    parentFolderNames.push(folderName)
-  }
-  return parentFolderNames
-}