Apply legacy plugin (#960)

Co-authored-by: Zongle Wang <[email protected]>

build.gradle

@@ -59,6 +59,7 @@ tasks.named('shadowJar', ShadowJar) {
     from rootProject.file('LICENSE')
     from rootProject.file('NOTICE')
     enableRelocation true
+    archiveClassifier = ''
 }
 
 tasks.named('ideaModule') {

src/docs/changes/README.md

@@ -5,6 +5,9 @@
 
 **Added**
 
+- Apply an empty plugin that has the legacy `com.github.johnrengelman.shadow` plugin ID.
+  This allows existing build logic to keep on reacting to the legacy plugin as the replacement is drop-in currently.
+
 **Changed**
 
 **Fixed**

src/main/groovy/com/github/jengelman/gradle/plugins/shadow/ShadowPlugin.groovy

@@ -1,5 +1,6 @@
 package com.github.jengelman.gradle.plugins.shadow
 
+import com.github.jengelman.gradle.plugins.shadow.legacy.LegacyShadowPlugin
 import com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar
 import org.gradle.api.Plugin
 import org.gradle.api.Project
@@ -12,6 +13,7 @@ class ShadowPlugin implements Plugin<Project> {
     void apply(Project project) {
         project.with {
             plugins.apply(ShadowBasePlugin)
+            plugins.apply(LegacyShadowPlugin)
             plugins.withType(JavaPlugin) {
                 plugins.apply(ShadowJavaPlugin)
             }

src/main/groovy/com/github/jengelman/gradle/plugins/shadow/legacy/LegacyShadowPlugin.groovy

@@ -0,0 +1,16 @@
+package com.github.jengelman.gradle.plugins.shadow.legacy
+
+import org.gradle.api.Plugin
+import org.gradle.api.Project
+
+/**
+ * Empty plugin to still have the com.github.johnrengelman.shadow plugin applied.
+ *
+ * This allows older build logic to keep on working as if that old plugin ID was applied.
+ */
+class LegacyShadowPlugin implements Plugin<Project> {
+    @Override
+    void apply(Project target) {
+        // Do nothing
+    }
+}

src/main/resources/META-INF/gradle-plugins/com.github.johnrengelman.shadow.properties

@@ -0,0 +1 @@
+implementation-class=com.github.jengelman.gradle.plugins.shadow.legacy.LegacyShadowPlugin

src/test/groovy/com/github/jengelman/gradle/plugins/shadow/ShadowPluginSpec.groovy

@@ -31,6 +31,7 @@ class ShadowPluginSpec extends PluginSpecification {
 
         then:
         project.plugins.hasPlugin(ShadowPlugin)
+        project.plugins.hasPlugin(com.github.jengelman.gradle.plugins.shadow.legacy.LegacyShadowPlugin)
 
         and:
         assert !project.tasks.findByName('shadowJar')