add checkVersionIsSnapshot task to CI and publish-snapshot actions

Author: RBusarow

.github/workflows/kotlin.yml

@@ -80,7 +80,7 @@ jobs :
           gradle-dependencies-cache-key : |
             gradle/libs.versions.toml
           arguments : |
-            check apiCheck artifactsCheck dependencyGuard lint ktlintCheck jvmWorkflowNodeBenchmarkJar --no-daemon --stacktrace --continue
+            check apiCheck checkVersionIsSnapshot artifactsCheck dependencyGuard lint ktlintCheck jvmWorkflowNodeBenchmarkJar --no-daemon --stacktrace --continue
           concurrent : true
           gradle-build-scan-report : false
           gradle-distribution-sha-256-sum-warning : false

.github/workflows/publish-snapshot.yml

@@ -22,6 +22,9 @@ jobs:
           distribution: 'zulu'
           java-version: 11
 
+      - name : Check for -SNAPSHOT version
+        run: ./gradlew checkVersionIsSnapshot --no-daemon
+
       - name : Publish Snapshots
         run: |
           ./gradlew clean build --no-daemon

buildSrc/src/main/java/published.gradle.kts

@@ -16,3 +16,13 @@ version = project.property("VERSION_NAME") as String
 mavenPublish {
   sonatypeHost = SonatypeHost.S01
 }
+
+tasks.register("checkVersionIsSnapshot") {
+  doLast {
+    val expected = "-SNAPSHOT"
+    require((version as String).endsWith(expected)) {
+      "The project's version name must be suffixed with `$expected` when checked in" +
+        " to the main branch, but instead it's `$version`."
+    }
+  }
+}