fix(transform): don't remove 'v' from tag

Don't remove the leading `v` from a git tag found to be a semantically
valid version tag.

Previous behavior was based on a third-party package that removed the
leading `v` in front of a semantically valid version tag.

Though the behavior was correct for that package, we need to preserve
the leading `v` for the purpose of publishing.

If the tag has a leading `v`, perhaps because the user has specifically
tagged their repository using a leading `v`, they likely expect that `v`
to be used as the tag on GitHub, and as the name of the GitHub release
page associated with that tag.

Therefore we must preserve the leading `v` in all semantically valid
version tags.

Closes #44

package.json

@@ -39,14 +39,14 @@
   "dependencies": {
     "conventional-changelog": "^1.1.0",
     "dateformat": "^1.0.11",
-    "find-versions": "^2.0.0",
     "git-semver-tags": "^1.0.0",
     "github": "^0.2.4",
     "lodash.merge": "^4.0.2",
     "meow": "^3.3.0",
     "object-assign": "^4.0.1",
     "q": "^1.4.1",
     "semver": "^5.0.1",
+    "semver-regex": "^1.0.0",
     "through2": "^2.0.0"
   },
   "devDependencies": {

src/transform.js

@@ -1,11 +1,11 @@
 'use strict';
 
 var dateFormat = require('dateformat');
-var findVersions = require('find-versions');
+var semverRegex = require('semver-regex');
 
 function transform(chunk, cb) {
   if (typeof chunk.gitTags === 'string') {
-    chunk.version = findVersions(chunk.gitTags)[0];
+    chunk.version = (chunk.gitTags.match(semverRegex()) || [])[0];
   }
 
   if (chunk.committerDate) {

src/transform.spec.js

@@ -7,6 +7,24 @@ var transform = require('./transform');
 
 var expect = chai.expect;
 
+/*
+  The contents of `gitTags` is generated by the `git-raw-commits` package, which runs the following command:
+
+    git log --format=%B%n-hash-%n%H%n-gitTags-%n%d%n-committerDate-%n%ci
+
+  That command returns a list of log entries with output in the following form per commit:
+
+    -hash-
+    e26c9a71a638ef9d4e12c2512fcdf813399559a1
+    -gitTags-
+     (tag: 1.1.8)
+    -committerDate-
+    2017-05-29 13:42:41 -0500
+    1.1.8
+
+  The value of `gitTags` is the line between `-gitTags-` and `-committerDate-`.
+*/
+
 describe('transform', function() {
   beforeEach(function() {
     this.chunk = {
@@ -31,7 +49,7 @@ describe('transform', function() {
   });
 
   it('should not match invalid semantic version tag', function(done) {
-    this.chunk.gitTags = ' tag: release-18';
+    this.chunk.gitTags = ' (tag: release-18)';
 
     transform(this.chunk, function(err, chunk) {
       expect(chunk.version).to.be.undefined;
@@ -40,11 +58,38 @@ describe('transform', function() {
   });
 
   it('should match valid semantic version tag', function(done) {
-    this.chunk.gitTags = ' tag: release-18, tag: 1.1.20';
+    this.chunk.gitTags = ' (tag: 1.1.20)';
+
+    transform(this.chunk, function(err, chunk) {
+      expect(chunk.version).to.equal('1.1.20');
+      done();
+    });
+  });
+
+  it('should match valid semantic version tag containing a leading `v`', function(done) {
+    this.chunk.gitTags = ' (tag: v1.1.20)';
+
+    transform(this.chunk, function(err, chunk) {
+      expect(chunk.version).to.equal('v1.1.20');
+      done();
+    });
+  });
+
+  it('should find valid semantic version tag out of many tags', function(done) {
+    this.chunk.gitTags = ' (HEAD -> master, tag: something, tag: 1.1.20, origin/master, origin/HEAD)';
 
     transform(this.chunk, function(err, chunk) {
       expect(chunk.version).to.equal('1.1.20');
       done();
     });
   });
+
+  it('should match first semantic version tag when there are multiple valid tags', function(done) {
+    this.chunk.gitTags = ' (tag: 1.1.19, tag: 1.1.20)';
+
+    transform(this.chunk, function(err, chunk) {
+      expect(chunk.version).to.equal('1.1.19');
+      done();
+    });
+  });
 });