Upgrade Gradle wrapper, bump dependencies, and refactor build

.github/workflows/ci.yml

@@ -16,11 +16,11 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Set up JDK 17
+      - name: Set up JDK 25
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: 17
+          java-version: 25
 
       - name: Set up Gradle
         uses: gradle/actions/setup-gradle@v4
@@ -33,11 +33,11 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Set up JDK 17
+      - name: Set up JDK 25
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: 17
+          java-version: 25
 
       - name: Set up Gradle
         uses: gradle/actions/setup-gradle@v4

Makefile

@@ -1,5 +1,5 @@
 .PHONY: default help clean build lint format detekt detekt-baseline tests uberjar uber \
-        cc run heroku logs versions upgrade-wrapper
+        cc run versions upgrade-wrapper
 
 GRADLE_VERSION := $(shell sed -n 's/^gradle-wrapper = "\(.*\)"/\1/p' gradle/libs.versions.toml)
 
@@ -42,19 +42,13 @@ cc: ## Continuous compilation (watches for changes)
 run: ## Start the content server locally (port 8080)
 	./gradlew run
 
-heroku: ## Deploy by pushing master to Heroku
-	git push heroku master
-
-logs: ## Tail Heroku logs
-	heroku logs --tail
-
 versions: ## Check for dependency updates
 	./gradlew dependencyUpdates --no-configuration-cache --no-parallel
 
-# Gradle's documented upgrade procedure: the first run rewrites
-# gradle-wrapper.properties using the *old* wrapper jar; the second run
-# regenerates the wrapper itself with the new version.
-upgrade-wrapper: _require-gradle-version ## Upgrade Gradle wrapper to version in libs.versions.toml
+upgrade-wrapper: _require-gradle-version ## Upgrade the Gradle wrapper to the catalog version
+	# Gradle's documented upgrade procedure: the first run rewrites
+	# gradle-wrapper.properties using the *old* wrapper jar; the second run
+	# regenerates the wrapper itself with the new version.
 	./gradlew wrapper --gradle-version=$(GRADLE_VERSION) --distribution-type=bin
 	./gradlew wrapper --gradle-version=$(GRADLE_VERSION) --distribution-type=bin
 

build.gradle.kts

@@ -1,21 +1,24 @@
+import com.github.benmanes.gradle.versions.updates.DependencyUpdatesTask
+import org.gradle.api.tasks.testing.logging.TestExceptionFormat
 import org.gradle.api.tasks.testing.logging.TestLogEvent
+import org.gradle.kotlin.dsl.named
+import org.gradle.kotlin.dsl.withType
+import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 
 plugins {
-  application
   alias(libs.plugins.kotlin.jvm)
   alias(libs.plugins.versions)
   alias(libs.plugins.ktor.plugin)
   alias(libs.plugins.detekt)
   alias(libs.plugins.kotlinter)
 }
 
-// This is for ./gradlew run
+description = "ReadingBat Site"
+
 application {
   mainClass = "ContentServerKt"
 }
 
-description = "ReadingBat Site"
-
 dependencies {
   implementation(libs.readingbat.core)
   implementation(libs.core.utils)
@@ -24,43 +27,102 @@ dependencies {
   testImplementation(libs.bundles.testing)
 }
 
-kotlin {
-  jvmToolchain(libs.versions.jvm.get().toInt())
+tasks.register("stage") {
+  group = "distribution"
+  description = "Clean-builds the project for deployment."
+  dependsOn("clean", "build")
 }
 
-detekt {
-  source.setFrom("src/main/kotlin", "src/test/kotlin")
-  buildUponDefaultConfig = true
-  parallel = true
+tasks.named("build") {
+  mustRunAfter("clean")
 }
 
-kotlinter {
-  ignoreFormatFailures = false
-  ignoreLintFailures = false
-  reporters = arrayOf("checkstyle", "plain")
+configureKotlin()
+configureDetekt()
+configureKotlinter()
+configureKtor()
+configureShadowJar()
+configureTest()
+configureVersions()
+
+fun Project.configureKotlin() {
+  kotlin {
+    jvmToolchain(libs.versions.jvm.get().toInt())
+  }
+
+  // Run the unused-return-value checker over production code only. Kotest's
+  // assertion DSL (e.g. shouldBe) returns its receiver, and tests intentionally
+  // discard that result, so applying the checker to the test source set would
+  // emit only false-positive warnings.
+  tasks.named<KotlinCompile>("compileKotlin") {
+    compilerOptions {
+      freeCompilerArgs.add("-Xreturn-value-checker=check")
+    }
+  }
 }
 
-tasks.register("stage") {
-  dependsOn("clean", "build")
+fun Project.configureDetekt() {
+  detekt {
+    source.setFrom("src/main/kotlin", "src/test/kotlin")
+    buildUponDefaultConfig = true
+    parallel = true
+  }
 }
 
-tasks.named("build") {
-  mustRunAfter("clean")
+fun Project.configureKotlinter() {
+  kotlinter {
+    ignoreFormatFailures = false
+    ignoreLintFailures = false
+    reporters = arrayOf("checkstyle", "plain")
+  }
 }
 
-tasks.shadowJar {
-  archiveFileName.set("server.jar")
-  isZip64 = true
-  duplicatesStrategy = DuplicatesStrategy.EXCLUDE
-  listOf("META-INF/*.SF", "META-INF/*.DSA", "META-INF/*.RSA", "LICENSE*").forEach(::exclude)
+fun Project.configureKtor() {
+  ktor {
+    fatJar {
+      archiveFileName = "server.jar"
+    }
+  }
 }
 
-tasks.test {
-  useJUnitPlatform()
+fun Project.configureShadowJar() {
+  // Ktor's `buildFatJar` task delegates to shadow; this block configures that output.
+  tasks.shadowJar {
+    isZip64 = true
+    duplicatesStrategy = DuplicatesStrategy.WARN
+    exclude("META-INF/*.SF", "META-INF/*.DSA", "META-INF/*.RSA")
+  }
+}
+
+fun Project.configureTest() {
+  tasks.test {
+    useJUnitPlatform()
+
+    testLogging {
+      events = setOf(TestLogEvent.PASSED, TestLogEvent.SKIPPED, TestLogEvent.FAILED, TestLogEvent.STANDARD_ERROR)
+      exceptionFormat = TestExceptionFormat.FULL
+      showStandardStreams = false
+    }
+  }
+}
+
+fun Project.configureVersions() {
+  // A pre-release qualifier is a `.` or `-` delimiter followed by a known unstable
+  // keyword. `m\d` matches milestones (`-M1`/`.M2`) without catching stable classifiers
+  // like `-macos`/`-MR1`, and the `[.-]` delimiter catches both dash-style (`-alpha`)
+  // and dot-style (Netty's `.Beta1`) qualifiers while leaving `-jre`/`.Final` stable.
+  val preReleaseQualifier =
+    Regex("""[.-](rc|beta|alpha|m\d|cr|snapshot|eap|dev|milestone|pre)""", RegexOption.IGNORE_CASE)
+
+  fun isNonStable(version: String): Boolean = preReleaseQualifier.containsMatchIn(version)
 
-  testLogging {
-    events = setOf(TestLogEvent.PASSED, TestLogEvent.SKIPPED, TestLogEvent.FAILED, TestLogEvent.STANDARD_ERROR)
-    exceptionFormat = org.gradle.api.tasks.testing.logging.TestExceptionFormat.FULL
-    showStandardStreams = false
+  tasks.withType<DependencyUpdatesTask>().configureEach {
+    notCompatibleWithConfigurationCache("the dependency updates plugin is not compatible with the configuration cache")
+    // Reject a pre-release candidate only when the current version is stable. For
+    // dependencies we intentionally track on a pre-release line (e.g. a detekt
+    // alpha), newer pre-releases are still surfaced as available updates.
+    rejectVersionIf {
+      isNonStable(candidate.version) && !isNonStable(currentVersion)
+    }
   }
 }

gradle/libs.versions.toml

@@ -1,14 +1,14 @@
 [versions]
-detekt = "2.0.0-alpha.3"
-gradle-wrapper = "9.5.1"
-jvm = "17"
-kotest = "6.1.11"
+detekt = "2.0.0-alpha.5"
+gradle-wrapper = "9.6.1"
+jvm = "25"
+kotest = "6.2.1"
 kotlin = "2.4.0"
 kotlinter = "5.5.0"
-ktor = "3.5.0"
+ktor = "3.5.1"
 logging = "8.0.4"
-readingbat = "3.1.8"
-utils = "2.9.0"
+readingbat = "3.2.1"
+utils = "2.9.3"
 versions = "0.54.0"
 
 [libraries]

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-9.5.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.6.1-bin.zip
 networkTimeout=10000
 retries=0
 retryBackOffMs=500

src/test/kotlin/ContentTests.kt

@@ -72,7 +72,7 @@ class ContentTests : StringSpec() {
           forEachGroup {
             forEachChallenge {
               forEachAnswer {
-                it shouldHaveAnswer correctAnswers[it.index]
+                it shouldHaveAnswer correctAnswers()[it.index]
               }
             }
           }