the slugs tests typeScript

src/slug.ts

@@ -0,0 +1,28 @@
+// Pure string logic for zettelclean. No Obsidian imports, so it is unit-testable
+// in isolation. The transform is always one-way (H1 -> filename), which lets us
+// freely drop characters without worrying about a reverse mapping.
+
+// A TIMEID is a leading run of 12 to 18 digits, ending at a dash or end-of-name.
+// 12-18 because collision-avoidance may append extra digits to a 14-digit stamp.
+const TIMEID_RE = /^(\d{12,18})(?=-|$)/;
+
+// Return the immutable id prefix, or null if this file is not a zettel.
+export function extractTimeId(basename: string): string | null {
+	const m = basename.match(TIMEID_RE);
+	return m?.[1] ?? null;
+}
+
+// H1 text -> kebab slug. sanifize as inspiration, deliberately simpler.
+export function generateSlug(heading: string): string {
+	return heading
+		.normalize('NFKD') // split accented letters into base + combining mark
+		.replace(/[̀-ͯ]/g, '') // strip the combining marks (c-cedilla -> c)
+		.toLowerCase()
+		.replace(/[^a-z0-9]+/g, '-') // any run of non-alphanumerics -> one dash
+		.replace(/^-+|-+$/g, ''); // trim leading/trailing dashes
+}
+
+// Reassemble; an empty slug collapses to the bare id.
+export function buildFilename(id: string, slug: string): string {
+	return slug ? `${id}-${slug}` : id;
+}