Fix sortReleases for non-semver tags

Fixes #81

src/releases.js

@@ -3,6 +3,7 @@ import { niceDate } from './utils'
 
 const MERGE_COMMIT_PATTERN = /^Merge (remote-tracking )?branch '.+'/
 const COMMIT_MESSAGE_PATTERN = /\n+([\S\s]+)/
+const NUMERIC_PATTERN = /^\d+(\.\d+)?$/
 
 export function parseReleases (commits, remote, latestVersion, options) {
   let release = newRelease(latestVersion)
@@ -43,7 +44,18 @@ export function parseReleases (commits, remote, latestVersion, options) {
 }
 
 export function sortReleases (a, b) {
-  if (a.tag && b.tag) return semver.rcompare(a.tag, b.tag)
+  if (a.tag && b.tag) {
+    if (semver.valid(a.tag) && semver.valid(b.tag)) {
+      return semver.rcompare(a.tag, b.tag)
+    }
+    if (NUMERIC_PATTERN.test(a.tag) && NUMERIC_PATTERN.test(b.tag)) {
+      return parseFloat(a.tag) < parseFloat(b.tag) ? 1 : -1
+    }
+    if (a.tag === b.tag) {
+      return 0
+    }
+    return a.tag < b.tag ? 1 : -1
+  }
   if (a.tag) return 1
   if (b.tag) return -1
   return 0

test/releases.js

@@ -84,4 +84,17 @@ describe('sortReleases', () => {
     expect(sortReleases({ tag: null }, { tag: '0.1.0' })).to.equal(-1)
     expect(sortReleases({ tag: null }, { tag: null })).to.equal(-0)
   })
+
+  it('supports non-semver tags', () => {
+    expect(sortReleases({ tag: 'abc' }, { tag: 'def' })).to.equal(1)
+    expect(sortReleases({ tag: 'def' }, { tag: 'abc' })).to.equal(-1)
+    expect(sortReleases({ tag: 'abc' }, { tag: 'abc' })).to.equal(0)
+  })
+
+  it('supports non-semver numeric tags', () => {
+    expect(sortReleases({ tag: '22.1' }, { tag: '22.0' })).to.equal(-1)
+    expect(sortReleases({ tag: '22.0' }, { tag: '22.1' })).to.equal(1)
+    expect(sortReleases({ tag: '123.0' }, { tag: '22.1' })).to.equal(-1)
+    expect(sortReleases({ tag: '0.1' }, { tag: '0.01' })).to.equal(-1)
+  })
 })