Merge pull request #53 from lucahuettner/feat/expose-release-count-opt

feat: Expose release count option

Author: TimothyJones

README.md

@@ -343,6 +343,27 @@ If you've already run `commit-and-tag-version` when creating your release, you m
 the version, by using `commit-and-tag-version --skip.bump`. By default, tagging with an already existing tag make `git` fails.
 You can add the `--tag-force` flag to make use of `-f` option when calling `git tag`, then the existing version tag will be replaced.
 
+### Generate changelogs for old releases
+
+Normally only the changelog for the last release will be generated and prepended to the `changelog.md`. If you want to generate changelogs for previous releases you can do so by setting the `releaseCount` option like described [here](https://github.com/conventional-changelog/conventional-changelog/tree/master/packages/conventional-changelog-core#releasecount).
+
+When setting releaseCount=0 the whole changelog gets regenerated and replaced.
+
+You can set the option either in the`.versionrc` file or inside `package.json` like below
+
+```json
+//.versionrc
+{
+  "releaseCount": 0
+}
+
+//package.json
+
+"commit-and-tag-version": {
+  "releaseCount": 0
+}
+```
+
 ### CLI Help
 
 ```sh

command.js

@@ -73,6 +73,11 @@ const yargs = require('yargs')
     type: 'string',
     default: defaults.tagPrefix
   })
+  .option('release-count', {
+    describe: 'How many releases of changelog you want to generate. It counts from the upcoming release. Useful when you forgot to generate any previous changelog. Set to 0 to regenerate all.',
+    type: 'number',
+    default: defaults.releaseCount
+  })
   .option('tag-force', {
     describe: 'Allow tag replacement',
     type: 'boolean',

defaults.js

@@ -8,6 +8,7 @@ const defaults = {
   commitAll: false,
   silent: false,
   tagPrefix: 'v',
+  releaseCount: 1,
   scripts: {},
   skip: {},
   dryRun: false,

lib/lifecycles/changelog.js

@@ -23,7 +23,7 @@ function outputChangelog (args, newVersion) {
     createIfMissing(args)
     const header = args.header
 
-    let oldContent = args.dryRun ? '' : fs.readFileSync(args.infile, 'utf-8')
+    let oldContent = args.dryRun || args.releaseCount === 0 ? '' : fs.readFileSync(args.infile, 'utf-8')
     const oldContentStart = oldContent.search(START_OF_LAST_RELEASE_PATTERN)
     // find the position of the last release and remove header:
     if (oldContentStart !== -1) {
@@ -34,7 +34,8 @@ function outputChangelog (args, newVersion) {
     const changelogStream = conventionalChangelog({
       debug: args.verbose && console.info.bind(console, 'conventional-changelog'),
       preset: presetLoader(args),
-      tagPrefix: args.tagPrefix
+      tagPrefix: args.tagPrefix,
+      releaseCount: args.releaseCount
     }, context, { merges: null, path: args.path }, args.parserOpts, args.writerOpts)
       .on('error', function (err) {
         return reject(err)