add npm versions

closes ehmicky#8

src/normalize.js

@@ -7,14 +7,15 @@ export const normalizeIndex = function (index) {
   const indexItems = index.map(normalizeVersion)
   const versions = getAllVersions(indexItems)
   const majors = getMajors(indexItems)
-  return { versions, majors }
+  const nodeNpmVersions = getAllNodeNpmVersions(indexItems)
+  return { versions, majors, nodeNpmVersions }
 }
 
-const normalizeVersion = function ({ version, lts }) {
+const normalizeVersion = function ({ version, lts, npm }) {
   // Remove the leading `v`
   const versionA = version.slice(1)
   const major = semver.major(versionA)
-  return { version: versionA, major, lts }
+  return { version: versionA, major, lts, npm }
 }
 
 // Array with all version strings, sorted from most to least recent
@@ -26,6 +27,14 @@ const getVersionField = function ({ version }) {
   return version
 }
 
+// Array with all {node: ..., npm: ...} version pairs
+const getAllNodeNpmVersions = function (indexItems) {
+  return indexItems.map(({ version, npm }) => ({
+    node: version,
+    npm: npm || '0.0.0',
+  }))
+}
+
 // Array with all major releases latest version, sorted from most to least
 // recent. Includes `lts` name if any.
 const getMajors = function (indexItems) {

test/main.js

@@ -7,8 +7,28 @@ const isVersion = function (version) {
   return typeof version === 'string' && VERSION_REGEXP.test(version)
 }
 
+const isNodeNpmVersion = function (nodeNpmVersion) {
+  return (
+    typeof nodeNpmVersion.node === 'string' &&
+    VERSION_REGEXP.test(nodeNpmVersion.node) &&
+    typeof nodeNpmVersion.npm === 'string' &&
+    NPM_VERSION_REGEXP.test(nodeNpmVersion.npm)
+  )
+}
+
 const VERSION_REGEXP = /^\d+\.\d+\.\d+$/u
 
+/**
+ * Real examples:
+ * 1.1.0-beta-4
+ * 1.1.0-alpha-6
+ * 1.1.18
+ * 6.5.0-next.0
+ * 1.1.0-3
+ */
+const NPM_VERSION_REGEXP =
+  /^\d+\.\d+\.\d+((-(alpha|beta)-\d+)|(-next\.\d+)|(-\d+))?$/u
+
 test('"versions" are present', async (t) => {
   const { versions } = await allNodeVersions({ fetch: true })
 
@@ -24,6 +44,23 @@ test('"versions" are sorted', async (t) => {
   t.deepEqual(versions, sortedVersions)
 })
 
+test('"nodeNpmVersions" are present', async (t) => {
+  const { nodeNpmVersions } = await allNodeVersions({ fetch: true })
+
+  t.true(Array.isArray(nodeNpmVersions))
+  t.true(nodeNpmVersions.every(isNodeNpmVersion))
+})
+
+test('"nodeNpmVersions" are sorted', async (t) => {
+  const { nodeNpmVersions } = await allNodeVersions({ fetch: true })
+  // eslint-disable-next-line fp/no-mutating-methods, id-length
+  const sortedVersions = [...nodeNpmVersions].sort((a, b) =>
+    semver.rcompare(a.node, b.node),
+  )
+
+  t.deepEqual(nodeNpmVersions, sortedVersions)
+})
+
 test('"majors" are present', async (t) => {
   const { majors } = await allNodeVersions({ fetch: true })