From 2f7c3abadcee1e47dc653fb3b60459b4e37ed4de Mon Sep 17 00:00:00 2001
From: Pete Cook <pete@cookpete.com>
Date: Sun, 23 May 2021 18:04:23 +0100
Subject: [PATCH] Add --hide-empty-releases

Fixes https://github.com/cookpete/auto-changelog/issues/189
---
 README.md        |  1 +
 src/releases.js  | 10 +++++++++-
 src/run.js       |  1 +
 test/releases.js | 11 +++++++++++
 4 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 180e2ef1..799b411c 100644
--- a/README.md
+++ b/README.md
@@ -45,6 +45,7 @@ Options:
       --sort-commits [property]       # sort commits by property [relevance, date, date-desc, subject, subject-desc], default: relevance
       --release-summary               # display tagged commit message body as release summary
       --unreleased-only               # only output unreleased changes
+      --hide-empty-releases           # hide empty releases
       --hide-credit                   # hide auto-changelog credit
       --handlebars-setup [file]       # handlebars setup file
       --append-git-log [string]       # string to append to git log command
diff --git a/src/releases.js b/src/releases.js
index e8c81898..2904fc2b 100644
--- a/src/releases.js
+++ b/src/releases.js
@@ -5,7 +5,7 @@ const MERGE_COMMIT_PATTERN = /^Merge (remote-tracking )?branch '.+'/
 const COMMIT_MESSAGE_PATTERN = /\n+([\S\s]+)/
 
 const parseReleases = async (tags, options, onParsed) => {
-  return Promise.all(tags.map(async tag => {
+  const releases = await Promise.all(tags.map(async tag => {
     const commits = await fetchCommits(tag.diff, options)
     const merges = commits.filter(commit => commit.merge).map(commit => commit.merge)
     const fixes = commits.filter(commit => commit.fixes).map(commit => ({ fixes: commit.fixes, commit }))
@@ -27,6 +27,7 @@ const parseReleases = async (tags, options, onParsed) => {
       fixes
     }
   }))
+  return releases.filter(filterReleases(options))
 }
 
 const filterCommits = merges => commit => {
@@ -80,6 +81,13 @@ const getSummary = (message, { releaseSummary }) => {
   return null
 }
 
+const filterReleases = options => ({ merges, fixes, commits }) => {
+  if (options.hideEmptyReleases && (merges.length + fixes.length + commits.length) === 0) {
+    return false
+  }
+  return true
+}
+
 module.exports = {
   parseReleases
 }
diff --git a/src/run.js b/src/run.js
index 29e1f718..9406d2a3 100644
--- a/src/run.js
+++ b/src/run.js
@@ -48,6 +48,7 @@ const getOptions = async argv => {
     .option('--sort-commits <property>', `sort commits by property [relevance, date, date-desc], default: ${DEFAULT_OPTIONS.sortCommits}`)
     .option('--release-summary', 'use tagged commit message body as release summary')
     .option('--unreleased-only', 'only output unreleased changes')
+    .option('--hide-empty-releases', 'hide empty releases')
     .option('--hide-credit', 'hide auto-changelog credit')
     .option('--handlebars-setup <file>', 'handlebars setup file')
     .option('--append-git-log <string>', 'string to append to git log command')
diff --git a/test/releases.js b/test/releases.js
index e8009503..f86ed99e 100644
--- a/test/releases.js
+++ b/test/releases.js
@@ -117,4 +117,15 @@ describe('parseReleases', () => {
     expect(releases[0].commits).to.have.lengthOf(1)
     expect(releases[0].commits[0]).to.include({ subject: 'First commit' })
   })
+
+  it('hides empty releases', async () => {
+    const map = {
+      'v1.0.0': []
+    }
+    mock('fetchCommits', diff => Promise.resolve(map[diff]))
+    const options = { hideEmptyReleases: true }
+    const tags = [{ tag: 'v1.0.0', date: '2000-01-01', diff: 'v1.0.0' }]
+    const releases = await parseReleases(tags, options)
+    expect(releases).to.have.lengthOf(0)
+  })
 })