feat(mystery): parseItem — markdown to typed Item

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/world/loader.test.ts

@@ -1,5 +1,5 @@
 import { describe, it, expect } from 'vitest'
-import { parseRoom } from './loader'
+import { parseRoom, parseItem } from './loader'
 
 const FOYER_MD = `---
 id: foyer
@@ -161,3 +161,56 @@ items: []
     expect(() => parseRoom(md, 'rooms/r.md')).toThrow(/exitDRequires is set but exitDLockedText is missing/)
   })
 })
+
+// Add to the bottom of loader.test.ts
+
+const LAMP_MD = `---
+id: lamp
+names: [lamp, oil lamp, torch]
+short: an oil lamp
+takeable: true
+initialState:
+  lit: false
+---
+
+An iron oil lamp with a glass chimney. Currently unlit.
+`
+
+describe('parseItem', () => {
+  it('parses an item with state', () => {
+    const item = parseItem(LAMP_MD, 'items/lamp.md')
+    expect(item).toEqual({
+      id: 'lamp',
+      names: ['lamp', 'oil lamp', 'torch'],
+      short: 'an oil lamp',
+      long: 'An iron oil lamp with a glass chimney. Currently unlit.',
+      initialState: { lit: false },
+      takeable: true,
+    })
+  })
+
+  it('uses empty initialState when omitted', () => {
+    const md = `---
+id: x
+names: [x]
+short: x
+takeable: false
+---
+
+The long description.
+`
+    const item = parseItem(md, 'items/x.md')
+    expect(item.initialState).toEqual({})
+  })
+
+  it('throws when body is empty', () => {
+    const md = `---
+id: x
+names: [x]
+short: x
+takeable: false
+---
+`
+    expect(() => parseItem(md, 'items/x.md')).toThrow(/empty long description/i)
+  })
+})

src/world/loader.ts

@@ -1,7 +1,7 @@
 import matter from 'gray-matter'
-import type { Room, RoomDescriptions } from './types'
+import type { Room, RoomDescriptions, Item } from './types'
 import type { Direction } from '../engine/types'
-import { roomFrontmatterSchema } from './schema'
+import { roomFrontmatterSchema, itemFrontmatterSchema } from './schema'
 
 const WIKILINK = /^\[\[([^\]|]+)(?:\|[^\]]*)?\]\]$/
 
@@ -97,3 +97,21 @@ export function parseRoom(raw: string, sourcePath: string): Room {
   if (fm.safe) room.safe = fm.safe
   return room
 }
+
+export function parseItem(raw: string, sourcePath: string): Item {
+  const parsed = matter(raw)
+  const frontmatter = stripWikilink(parsed.data) as Record<string, unknown>
+  const fm = itemFrontmatterSchema.parse(frontmatter)
+  const long = parsed.content.trim()
+  if (long.length === 0) {
+    throw new Error(`${sourcePath}: empty long description`)
+  }
+  return {
+    id: fm.id,
+    names: fm.names,
+    short: fm.short,
+    long,
+    initialState: fm.initialState,
+    takeable: fm.takeable,
+  }
+}