Add Detekt to the build (#422)

* Add Detekt to the build

* Add detekt baseline

Author: RenFraser

.github/workflows/build.yml

@@ -24,3 +24,6 @@ jobs:
       - uses: gradle/gradle-build-action@v2
       - name: Build
         run: ./gradlew :server:build :shared:build -PjavaVersion=${{ matrix.java }}
+      - uses: gradle/gradle-build-action@v2
+      - name: Detekt
+        run: ./gradlew detekt

build.gradle.kts

@@ -1,9 +1,13 @@
+import io.gitlab.arturbosch.detekt.Detekt
+import io.gitlab.arturbosch.detekt.DetektCreateBaselineTask
+
 // TODO: change the hardcoded 1.6.10 to kotlinVeresion that lives in project props
 // We could use a buildSrc script for this.
 // See: https://github.com/gradle/kotlin-dsl-samples/issues/802
 plugins {
     kotlin("jvm") version "1.8.10"
     `maven-publish`
+    id("io.gitlab.arturbosch.detekt") version "1.22.0"
 }
 
 repositories {
@@ -33,3 +37,49 @@ configure(subprojects.filter { it.name != "grammars" }) {
         }
     }
 }
+
+detekt {
+    allRules = false // activate all available (even unstable) rules.
+    buildUponDefaultConfig = true // preconfigure defaults
+    parallel = true
+    config = files("$rootDir/detekt.yml")
+    baseline = file("$rootDir/detekt_baseline.xml")
+    source = files(projectDir)
+}
+
+// Registers a baseline for Detekt.
+//
+// The way it works is that you set create "baseline" for Detekt
+// by running this task. It will then creatae a detekt-baseline.xml which
+// contains a list of current issues found within the project.
+// Then every time you run the "detekt" task it will only report errors
+// that are not in the baseline config.
+//
+// We should routinely run this task and commit the baseline file as we
+// fix detekt issues so that we can prevent regressions.
+tasks.register<DetektCreateBaselineTask>("createDetektBaseline") {
+    description = "Overrides current baseline."
+    buildUponDefaultConfig.set(true)
+    ignoreFailures.set(true)
+    parallel.set(true)
+    setSource(files(projectDir))
+    config.setFrom(files("$rootDir/detekt.yml"))
+    baseline.set(file("$rootDir/detekt_baseline.xml"))
+    include("**/*.kt")
+    include("**/*.kts")
+    exclude("shared/build/**/*.*")
+    exclude("server/build/**/*.*")
+}
+
+tasks.withType<Detekt>().configureEach {
+    reports {
+        html.required.set(true)
+        md.required.set(true)
+    }
+}
+
+tasks.withType<Detekt>().configureEach {
+    jvmTarget = "11"
+}
+
+tasks.check.get().dependsOn(tasks.detekt)

detekt.yml

@@ -0,0 +1,3 @@
+config:
+  validation: true # verifies that this config file is valid
+  warningsAsErrors: false