minor: Fix sonarcube warnings

.sonarcloud.properties

@@ -1 +1 @@
-sonar.cpd.exclusions=/core/src/test/**/*.scala,integration-tests/src/test/**/*.scala
+sonar.cpd.exclusions=**/*Spec.*,**/*Test.*,**/*Tests.*

core/src/test/scala/za/co/absa/spline/harvester/conf/HadoopConfigurationTest.scala

@@ -29,5 +29,8 @@ object HadoopConfigurationTest {
   Configuration.addDefaultResource(
     s"${this.getClass.getPackage.getName.replaceAllLiterally(".", "/")}/hdfs-test-conf.xml")
 
-  def init(): Unit = {}
+  def init(): Unit = {
+    // A singleton activator.
+    // Called from the class instances to ensure execution of the companion object's constructor code.
+  }
 }

core/src/test/scala/za/co/absa/spline/harvester/postprocessing/DataSourcePasswordReplacingFilterSpec.scala

@@ -77,12 +77,12 @@ class DataSourcePasswordReplacingFilterSpec extends AnyFlatSpec with Matchers wi
       "b" -> Seq(null),
       "c" -> None,
       "m" -> Map(
-        "url" -> "jdbc:postgresql://bob:secret@someHost:somePort/someDB",
+        "url" -> "jdbc:postgresql://bob:secret@someHost:somePort/someDB", // NOSONAR
         "dbtable" -> "someTable",
         "user" -> "someUser",
         "PASSPHRASE" -> "somePassword" // NOSONAR
       ),
-      "url" -> "jdbc:postgresql://bob:secret@someHost:somePort/someDB",
+      "url" -> "jdbc:postgresql://bob:secret@someHost:somePort/someDB", // NOSONAR
       "dbtable" -> "someTable",
       "user" -> "someUser",
       "password" -> "somePassword" // NOSONAR
@@ -92,14 +92,14 @@ class DataSourcePasswordReplacingFilterSpec extends AnyFlatSpec with Matchers wi
       "a" -> 42,
       "b" -> Seq(null),
       "c" -> None,
-      "url" -> "jdbc:postgresql://bob:*****@someHost:somePort/someDB",
+      "url" -> "jdbc:postgresql://bob:*****@someHost:somePort/someDB", // NOSONAR
       "m" -> Map(
-        "url" -> "jdbc:postgresql://bob:*****@someHost:somePort/someDB",
+        "url" -> "jdbc:postgresql://bob:*****@someHost:somePort/someDB", // NOSONAR
         "dbtable" -> "someTable",
         "user" -> "someUser",
         "PASSPHRASE" -> "*****" // NOSONAR
       ),
-      "url" -> "jdbc:postgresql://bob:*****@someHost:somePort/someDB",
+      "url" -> "jdbc:postgresql://bob:*****@someHost:somePort/someDB", // NOSONAR
       "dbtable" -> "someTable",
       "user" -> "someUser",
       "password" -> "*****" // NOSONAR

examples/src/main/scala/za/co/absa/spline/SparkApp.scala

@@ -47,5 +47,5 @@ abstract class SparkApp
    */
   val spark: SparkSession = sparkBuilder.getOrCreate()
 
-  protected override def _sqlContext: SQLContext = spark.sqlContext
+  protected override def _sqlContext: SQLContext = spark.sqlContext // NOSONAR
 }

integration-tests/src/main/scala/za/co/absa/spline/test/LineageWalker.scala

@@ -18,40 +18,68 @@ package za.co.absa.spline.test
 
 import za.co.absa.spline.producer.model._
 
+/**
+ * A class to walk through the execution plan.
+ *
+ * @param allOpMap A map of all operations in the execution plan.
+ * @param funMap   A map of all functional expressions in the execution plan.
+ * @param litMap   A map of all literals in the execution plan.
+ * @param attrMap  A map of all attributes in the execution plan.
+ */
 class LineageWalker(
   allOpMap: Map[String, Operation],
   funMap: Map[String, FunctionalExpression],
   litMap: Map[String, Literal],
   attrMap: Map[String, Attribute]
 ) {
 
-  def attributeById(attributeId: String): Attribute = attrMap(attributeId)
-
-  def operationById(operationId: String): Operation = allOpMap(operationId)
-
-  def dependsOn(att: Attribute, onAtt: Attribute): Boolean = {
-    dependsOnRec(AttrRef(att.id), onAtt.id)
+  /**
+   * Retrieves an attribute by its ID.
+   *
+   * @param attributeId The ID of the attribute.
+   * @return The attribute with the given ID.
+   */
+  def getAttributeById(attributeId: String): Attribute = attrMap(attributeId)
+
+  /**
+   * Retrieves an operation by its ID.
+   *
+   * @param operationId The ID of the operation.
+   * @return The operation with the given ID.
+   */
+  def getOperationById(operationId: String): Operation = allOpMap(operationId)
+
+  /**
+   * Checks if an attribute depends on another attribute.
+   *
+   * @param sourceAttribute The attribute to check.
+   * @param targetAttribute The attribute that the first attribute may depend on.
+   * @return True if the first attribute depends on the second attribute, false otherwise.
+   */
+  def dependsOn(sourceAttribute: Attribute, targetAttribute: Attribute): Boolean = {
+    dependsOnRecursively(AttrRef(sourceAttribute.id), targetAttribute.id)
   }
 
-  private def dependsOnRec(refs: Seq[AttrOrExprRef], id: String): Boolean =
-    refs.exists(dependsOnRec(_, id))
+  private def dependsOnRecursively(refs: Seq[AttrOrExprRef], attrId: String): Boolean =
+    refs.exists(dependsOnRecursively(_, attrId))
 
-  private def dependsOnRec(ref: AttrOrExprRef, id: String): Boolean = ref match {
-    case AttrRef(attrIfd) =>
-      if (attrIfd == id) true
-      else dependsOnRec(attrMap(attrIfd).childRefs, id)
+  private def dependsOnRecursively(ref: AttrOrExprRef, targetAttrId: String): Boolean = ref match {
+    case AttrRef(attrId) =>
+      attrId == targetAttrId || dependsOnRecursively(attrMap(attrId).childRefs, targetAttrId)
     case ExprRef(exprId) =>
-      if (exprId == id) true
-      else {
-        if (litMap.contains("exprId")) false
-        else dependsOnRec(funMap(exprId).childRefs, id)
-      }
+      funMap.get(exprId).exists(expr => dependsOnRecursively(expr.childRefs, targetAttrId))
   }
 
 }
 
 object LineageWalker {
 
+  /**
+   * Creates a LineageWalker instance from an execution plan.
+   *
+   * @param plan The execution plan.
+   * @return A LineageWalker instance.
+   */
   def apply(plan: ExecutionPlan): LineageWalker = {
     val allOpMap = plan.operations.all
       .map(op => op.id -> op)

integration-tests/src/main/scala/za/co/absa/spline/test/ProducerModelImplicits.scala

@@ -26,11 +26,11 @@ object ProducerModelImplicits {
   implicit class OperationOps(val operation: Operation) extends AnyVal {
 
     def outputAttributes(implicit walker: LineageWalker): IOAttributes = {
-      operation.output.map(walker.attributeById)
+      operation.output.map(walker.getAttributeById)
     }
 
     def childOperations(implicit walker: LineageWalker): Seq[Operation] = {
-      operation.childIds.map(walker.operationById)
+      operation.childIds.map(walker.getOperationById)
     }
 
     def childOperation(implicit walker: LineageWalker): Operation = {

integration-tests/src/main/scala/za/co/absa/spline/test/fixture/spline/SplineFixture.scala

@@ -15,7 +15,6 @@
 
 package za.co.absa.spline.test.fixture.spline
 
-import org.apache.commons.configuration.BaseConfiguration
 import org.apache.spark.sql.SparkSession
 
 
@@ -26,8 +25,6 @@ trait SplineFixture {
 }
 
 object SplineFixture {
-  def EmptyConf = new BaseConfiguration
-
   def extractTableIdentifier(params: Map[String, Any]): Map[String, Any] =
     params
       .apply("table").asInstanceOf[Map[String, _]]

pom.xml

@@ -166,8 +166,6 @@
                         <arg>-deprecation</arg>
                         <arg>-unchecked</arg>
                         <arg>-Ywarn-numeric-widen</arg>
-                        <!--<arg>-Ywarn-dead-code</arg>-->
-                        <!--<arg>-Ywarn-value-discard</arg>-->
                     </args>
                 </configuration>
                 <executions>