Packages: Avoid bumping the major version on prerelease packages (WordPress#74285)

* Packages: Avoid bumping the major version on prerelease packages

* Ensure packageJSONPath assigned for reading JSON file

* Clarify code comment on breaking changes

Co-authored-by: aduth <aduth@git.wordpress.org>
Co-authored-by: tyxla <tyxla@git.wordpress.org>

Author: aduth

bin/plugin/commands/common.js

@@ -36,12 +36,14 @@ async function findPluginReleaseBranchName( gitWorkingDirectoryPath ) {
  * @param {string[]}                  lines                Changelog content split into lines.
  * @param {('patch'|'minor'|'major')} [minimumVersionBump] Minimum version bump for the package.
  *                                                         Defaults to `patch`.
+ * @param {string}                    [currentVersion]     Current version of the package.
  *
  * @return {string|null} Version bump when applicable, or null otherwise.
  */
 function calculateVersionBumpFromChangelog(
 	lines,
-	minimumVersionBump = 'patch'
+	minimumVersionBump = 'patch',
+	currentVersion = '1.0.0'
 ) {
 	let changesDetected = false;
 	let versionBump = null;
@@ -63,9 +65,14 @@ function calculateVersionBumpFromChangelog(
 			break;
 		}
 
-		// A major version bump required. Stop processing.
+		// A major version bump required for stable packages. Stop processing.
 		if ( lineNormalized.startsWith( '### breaking change' ) ) {
-			versionBump = 'major';
+			if ( semver.lt( currentVersion, '1.0.0' ) ) {
+				versionBump = 'minor';
+			} else {
+				versionBump = 'major';
+			}
+
 			break;
 		}
 
@@ -89,6 +96,7 @@ function calculateVersionBumpFromChangelog(
 			versionBump = minimumVersionBump;
 		}
 	}
+
 	return versionBump;
 }
 

bin/plugin/commands/packages.js

@@ -1,13 +1,14 @@
 /**
  * External dependencies
  */
-const { command } = require( 'execa' );
 const path = require( 'path' );
-const glob = require( 'fast-glob' );
 const fs = require( 'fs' );
+const readline = require( 'readline' );
+const { join } = require( 'path' );
+const { command } = require( 'execa' );
+const glob = require( 'fast-glob' );
 const { inc: semverInc } = require( 'semver' );
 const { rimraf } = require( 'rimraf' );
-const readline = require( 'readline' );
 const SimpleGit = require( 'simple-git' );
 
 /**
@@ -24,7 +25,6 @@ const {
 	calculateVersionBumpFromChangelog,
 	findPluginReleaseBranchName,
 } = require( './common' );
-const { join } = require( 'path' );
 const pluginConfig = require( '../config' );
 
 /**
@@ -196,9 +196,15 @@ async function updatePackages( config ) {
 				lines.push( line );
 			}
 
+			const packageJSONPath = changelogPath.replace(
+				'CHANGELOG.md',
+				'package.json'
+			);
+			const { version } = readJSONFile( packageJSONPath );
 			let versionBump = calculateVersionBumpFromChangelog(
 				lines,
-				minimumVersionBump
+				minimumVersionBump,
+				version
 			);
 			const packageName = `@wordpress/${
 				changelogPath.split( '/' ).reverse()[ 1 ]
@@ -212,11 +218,6 @@ async function updatePackages( config ) {
 			) {
 				versionBump = minimumVersionBump;
 			}
-			const packageJSONPath = changelogPath.replace(
-				'CHANGELOG.md',
-				'package.json'
-			);
-			const { version } = readJSONFile( packageJSONPath );
 			const nextVersion =
 				versionBump !== null ? semverInc( version, versionBump ) : null;
 

bin/plugin/commands/test/common.js

@@ -61,16 +61,31 @@ describe( 'calculateVersionBumpFromChangelog', () => {
 
 	it( 'should return major version bump when breaking changes detected', () => {
 		expect(
-			calculateVersionBumpFromChangelog(
-				[
-					'First line',
-					'## Unreleased',
-					'### Breaking Changes',
-					'  - new item added',
-					'Fifth line',
-				],
-				'major'
-			)
+			calculateVersionBumpFromChangelog( [
+				'First line',
+				'## Unreleased',
+				'### Breaking Changes',
+				'  - new item added',
+				'Fifth line',
+			] )
 		).toBe( 'major' );
 	} );
+
+	describe( 'prerelease versions', () => {
+		it( 'should not bump the major even if breaking changes detected', () => {
+			expect(
+				calculateVersionBumpFromChangelog(
+					[
+						'First line',
+						'## Unreleased',
+						'### Breaking Changes',
+						'  - new item added',
+						'Fifth line',
+					],
+					'patch',
+					'0.1.0'
+				)
+			).toBe( 'minor' );
+		} );
+	} );
 } );