feat: add docs field and version helpers

README.md

@@ -215,6 +215,7 @@ interface Package {
   name: string
   description: string
   homepage: string
+  documentation: string  // docs URL (docs.rs, readthedocs, rubydoc, etc.)
   repository: string
   licenses: string       // SPDX-normalized
   keywords: string[]

src/core/types.ts

@@ -5,6 +5,7 @@ export interface Package {
   name: string
   description: string
   homepage: string
+  documentation: string
   repository: string
   licenses: string
   keywords: string[]

src/helpers.ts

@@ -1,4 +1,4 @@
-import type { Package, Version, Dependency, Maintainer } from './core/types.ts'
+import type { Package, Version, Dependency, Maintainer, URLBuilder } from './core/types.ts'
 import type { Client } from './core/client.ts'
 import { createFromPURL } from './core/purl.ts'
 
@@ -56,3 +56,44 @@ export async function bulkFetchPackages(
   await Promise.all(workers)
   return results
 }
+
+/**
+ * Select the best matching version from a list.
+ *
+ * Resolution order:
+ * 1. Exact match for `requested` (non-yanked/deprecated/retracted)
+ * 2. Exact match for `latest` (non-yanked/deprecated/retracted)
+ * 3. First available version with no negative status
+ *
+ * Returns `null` when no usable version exists.
+ */
+export function selectVersion(versions: Version[], options?: {
+  requested?: string
+  latest?: string
+}): Version | null {
+  const { requested, latest } = options ?? {}
+
+  if (requested) {
+    const exact = versions.find(v => v.number === requested && v.status === '')
+    if (exact) return exact
+  }
+
+  if (latest) {
+    const latestV = versions.find(v => v.number === latest && v.status === '')
+    if (latestV) return latestV
+  }
+
+  return versions.find(v => v.status === '') ?? null
+}
+
+/**
+ * Resolve the best documentation URL for a package.
+ *
+ * Fallback chain:
+ * 1. `package.documentation` (explicit docs URL from registry)
+ * 2. `package.homepage` (project homepage)
+ * 3. `urls.documentation()` (ecosystem default, e.g. docs.rs, rubydoc.info)
+ */
+export function resolveDocsUrl(pkg: Package, urls: URLBuilder, version?: string): string {
+  return pkg.documentation || pkg.homepage || urls.documentation(pkg.name, version)
+}

src/index.ts

@@ -22,6 +22,8 @@ export {
   fetchDependenciesFromPURL,
   fetchMaintainersFromPURL,
   bulkFetchPackages,
+  selectVersion,
+  resolveDocsUrl,
 } from './helpers.ts'
 
 // Types

src/registries/cargo.ts

@@ -130,12 +130,21 @@ class CargoRegistry implements Registry {
         name: crateData.name,
         description: crateData.description || '',
         homepage: crateData.homepage || '',
+        documentation: crateData.documentation || '',
         repository: normalizeRepositoryURL(crateData.repository || ''),
         licenses: normalizeLicense(data.versions[0]?.license || ''),
         keywords: crateData.keywords,
         namespace: '',
         latestVersion,
-        metadata: {},
+        metadata: {
+          downloads: crateData.downloads,
+          recentDownloads: crateData.recent_downloads,
+          categories: crateData.categories,
+          newestVersion: crateData.newest_version,
+          defaultVersion: crateData.max_version,
+          updatedAt: crateData.updated_at,
+          createdAt: crateData.created_at,
+        },
       }
     }
     catch (error) {
@@ -163,7 +172,11 @@ class CargoRegistry implements Registry {
           licenses: normalizeLicense(versionData.license),
           integrity: `sha256-${versionData.checksum}`,
           status,
-          metadata: {},
+          metadata: {
+            crateSize: versionData.crate_size,
+            features: versionData.features,
+            downloads: versionData.downloads,
+          },
         })
       }
 

src/registries/npm.ts

@@ -103,6 +103,7 @@ class NpmRegistry implements Registry {
         name: data.name,
         description: data.description || '',
         homepage: data.homepage || '',
+        documentation: '',
         repository: normalizeRepositoryURL(data.repository || ''),
         licenses,
         keywords: data.keywords || [],

src/registries/packagist.ts

@@ -89,6 +89,7 @@ class PackagistRegistry implements Registry {
         name: packageData.name,
         description: packageData.description || '',
         homepage: '',
+        documentation: '',
         repository: normalizeRepositoryURL(packageData.repository || latestVersionData.source?.url || ''),
         licenses,
         keywords: packageData.keywords || [],

src/registries/pypi.ts

@@ -86,6 +86,7 @@ class PyPIRegistry implements Registry {
         name: info.name,
         description: info.summary || info.description || '',
         homepage: info.project_urls?.['Homepage'] || '',
+        documentation: info.project_urls?.['Documentation'] || '',
         repository,
         licenses,
         keywords,

src/registries/rubygems.ts

@@ -83,6 +83,7 @@ class RubyGemsRegistry implements Registry {
         name: data.name,
         description: data.description || '',
         homepage: data.homepage_uri || '',
+        documentation: (data.metadata?.documentation_uri as string) || '',
         repository,
         licenses,
         keywords: [],

test/unit/helpers.test.ts

@@ -0,0 +1,128 @@
+import { describe, it, expect } from 'vitest'
+import type { Package, Version, URLBuilder } from '../../src/core/types.ts'
+import { selectVersion, resolveDocsUrl } from '../../src/helpers.ts'
+
+function version(num: string, status: '' | 'yanked' | 'deprecated' | 'retracted' = ''): Version {
+  return {
+    number: num,
+    publishedAt: new Date('2024-01-01T00:00:00Z'),
+    licenses: '',
+    integrity: '',
+    status,
+    metadata: {},
+  }
+}
+
+function pkg(overrides: Partial<Package> = {}): Package {
+  return {
+    name: 'test',
+    description: '',
+    homepage: '',
+    documentation: '',
+    repository: '',
+    licenses: '',
+    keywords: [],
+    namespace: '',
+    latestVersion: '1.0.0',
+    metadata: {},
+    ...overrides,
+  }
+}
+
+const stubUrls: URLBuilder = {
+  registry: () => '',
+  download: () => '',
+  documentation: (name: string, ver?: string) => `https://docs.example.com/${name}/${ver ?? 'latest'}`,
+  purl: () => '',
+}
+
+describe('selectVersion', () => {
+  it('returns exact requested version when available', () => {
+    const versions = [version('1.0.0'), version('2.0.0'), version('3.0.0')]
+    const result = selectVersion(versions, { requested: '2.0.0' })
+    expect(result?.number).toBe('2.0.0')
+  })
+
+  it('skips yanked requested version and falls back to latest', () => {
+    const versions = [version('1.0.0'), version('2.0.0', 'yanked'), version('3.0.0')]
+    const result = selectVersion(versions, { requested: '2.0.0', latest: '3.0.0' })
+    expect(result?.number).toBe('3.0.0')
+  })
+
+  it('skips deprecated requested version', () => {
+    const versions = [version('1.0.0'), version('2.0.0', 'deprecated')]
+    const result = selectVersion(versions, { requested: '2.0.0', latest: '1.0.0' })
+    expect(result?.number).toBe('1.0.0')
+  })
+
+  it('skips retracted requested version', () => {
+    const versions = [version('1.0.0'), version('2.0.0', 'retracted')]
+    const result = selectVersion(versions, { requested: '2.0.0', latest: '1.0.0' })
+    expect(result?.number).toBe('1.0.0')
+  })
+
+  it('falls back to first clean version when both requested and latest are unusable', () => {
+    const versions = [
+      version('1.0.0', 'yanked'),
+      version('2.0.0', 'yanked'),
+      version('3.0.0'),
+    ]
+    const result = selectVersion(versions, { requested: '1.0.0', latest: '2.0.0' })
+    expect(result?.number).toBe('3.0.0')
+  })
+
+  it('returns null when all versions are yanked', () => {
+    const versions = [version('1.0.0', 'yanked'), version('2.0.0', 'yanked')]
+    const result = selectVersion(versions, { requested: '1.0.0' })
+    expect(result).toBeNull()
+  })
+
+  it('returns null for empty version list', () => {
+    const result = selectVersion([], { requested: '1.0.0' })
+    expect(result).toBeNull()
+  })
+
+  it('works without options — returns first clean version', () => {
+    const versions = [version('1.0.0', 'yanked'), version('2.0.0')]
+    const result = selectVersion(versions)
+    expect(result?.number).toBe('2.0.0')
+  })
+
+  it('returns null when requested version does not exist', () => {
+    const versions = [version('1.0.0'), version('2.0.0')]
+    const result = selectVersion(versions, { requested: '9.9.9', latest: '2.0.0' })
+    expect(result?.number).toBe('2.0.0')
+  })
+})
+
+describe('resolveDocsUrl', () => {
+  it('prefers documentation field when set', () => {
+    const p = pkg({ documentation: 'https://serde.rs/docs' })
+    expect(resolveDocsUrl(p, stubUrls)).toBe('https://serde.rs/docs')
+  })
+
+  it('falls back to homepage when documentation is empty', () => {
+    const p = pkg({ homepage: 'https://serde.rs' })
+    expect(resolveDocsUrl(p, stubUrls)).toBe('https://serde.rs')
+  })
+
+  it('falls back to URLBuilder when both documentation and homepage are empty', () => {
+    const p = pkg()
+    expect(resolveDocsUrl(p, stubUrls, '1.0.0')).toBe('https://docs.example.com/test/1.0.0')
+  })
+
+  it('passes version to URLBuilder fallback', () => {
+    const p = pkg()
+    expect(resolveDocsUrl(p, stubUrls, '2.5.0')).toBe('https://docs.example.com/test/2.5.0')
+  })
+
+  it('uses latest when no version specified in URLBuilder fallback', () => {
+    const p = pkg()
+    expect(resolveDocsUrl(p, stubUrls)).toBe('https://docs.example.com/test/latest')
+  })
+
+  it('does not fall through when documentation is set even if homepage exists', () => {
+    const p = pkg({ documentation: 'https://docs.rs/serde', homepage: 'https://serde.rs' })
+    expect(resolveDocsUrl(p, stubUrls)).toBe('https://docs.rs/serde')
+  })
+})

test/unit/registries.test.ts

@@ -179,6 +179,12 @@ describe('Registry Modules', () => {
       expect(pkg.latestVersion).toBe('1.0.197')
       expect(pkg.keywords).toContain('serialization')
       expect(pkg.namespace).toBe('')
+      expect(pkg.documentation).toBe('https://docs.rs/serde')
+      expect(pkg.metadata.downloads).toBe(500000000)
+      expect(pkg.metadata.recentDownloads).toBe(5000000)
+      expect(pkg.metadata.newestVersion).toBe('1.0.197')
+      expect(pkg.metadata.updatedAt).toBe('2024-01-15T10:00:00Z')
+      expect(pkg.metadata.createdAt).toBe('2014-12-20T02:35:07Z')
     })
 
     it('should throw NotFoundError for missing cargo crate', async () => {
@@ -276,6 +282,9 @@ describe('Registry Modules', () => {
       expect(versions[0].integrity).toContain('sha256')
       expect(versions[1].number).toBe('1.0.197')
       expect(versions[1].status).toBe('')
+      expect(versions[0].metadata.crateSize).toBe(100000)
+      expect(versions[0].metadata.downloads).toBe(40000000)
+      expect(versions[1].metadata.crateSize).toBe(100000)
     })
   })
 
@@ -342,6 +351,7 @@ describe('Registry Modules', () => {
       expect(pkg.repository).toContain('github.com/psf/requests')
       expect(pkg.latestVersion).toBe('2.31.0')
       expect(pkg.namespace).toBe('')
+      expect(pkg.documentation).toBe('https://requests.readthedocs.io')
     })
 
     it('should throw NotFoundError for missing pypi package', async () => {