Using handleHasInitializer for all things with initializers

Fraunhofer-AISEC · Jan 17, 2025 · 083ff24 · 083ff24
1 parent 025c803
commit 083ff24
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Showing 3 changed files with 16 additions and 14 deletions.
diff --git a/cpg-analysis/src/main/kotlin/de/fraunhofer/aisec/cpg/analysis/MultiValueEvaluator.kt b/cpg-analysis/src/main/kotlin/de/fraunhofer/aisec/cpg/analysis/MultiValueEvaluator.kt
@@ -64,11 +64,9 @@ class MultiValueEvaluator : ValueEvaluator() {
         this.path += node
 
         when (node) {
-            is FieldDeclaration -> {
-                return evaluateInternal(node.initializer, depth + 1)
-            }
-            is NewArrayExpression -> return evaluateInternal(node.initializer, depth + 1)
-            is VariableDeclaration -> return handleVariableDeclaration(node, depth)
+            is FieldDeclaration -> return handleHasInitializer(node, depth)
+            is NewArrayExpression -> return handleHasInitializer(node, depth)
+            is VariableDeclaration -> return handleHasInitializer(node, depth)
             // For a literal, we can just take its value, and we are finished
             is Literal<*> -> return node.value
             is Reference -> return handlePrevDFG(node, depth)

diff --git a/cpg-analysis/src/main/kotlin/de/fraunhofer/aisec/cpg/analysis/ValueEvaluator.kt b/cpg-analysis/src/main/kotlin/de/fraunhofer/aisec/cpg/analysis/ValueEvaluator.kt
@@ -26,6 +26,7 @@
 package de.fraunhofer.aisec.cpg.analysis
 
 import de.fraunhofer.aisec.cpg.graph.AccessValues
+import de.fraunhofer.aisec.cpg.graph.HasInitializer
 import de.fraunhofer.aisec.cpg.graph.HasOperatorCode
 import de.fraunhofer.aisec.cpg.graph.Node
 import de.fraunhofer.aisec.cpg.graph.declarations.VariableDeclaration
@@ -87,8 +88,8 @@ open class ValueEvaluator(
         node?.let { this.path += it }
 
         when (node) {
-            is NewArrayExpression -> return evaluateInternal(node.initializer, depth)
-            is VariableDeclaration -> return handleVariableDeclaration(node, depth)
+            is NewArrayExpression -> return handleHasInitializer(node, depth)
+            is VariableDeclaration -> return handleHasInitializer(node, depth)
             // For a literal, we can just take its value, and we are finished
             is Literal<*> -> return node.value
             is Reference -> return handlePrevDFG(node, depth)
@@ -108,12 +109,16 @@ open class ValueEvaluator(
         return cannotEvaluate(node, this)
     }
 
-    protected fun handleVariableDeclaration(node: VariableDeclaration, depth: Int): Any? {
+    /**
+     * If a node declaration implements [HasInitializer], we can use the initializer to evaluate
+     * their value. If not, we can try to use [handlePrevDFG].
+     */
+    protected fun handleHasInitializer(node: HasInitializer, depth: Int): Any? {
         // If we have an initializer, we can use it. Otherwise, we can fall back to the prevDFG
         return if (node.initializer != null) {
             evaluateInternal(node.initializer, depth + 1)
         } else {
-            handlePrevDFG(node, depth)
+            handlePrevDFG(node as Node, depth)
         }
     }
 
@@ -405,9 +410,7 @@ open class ValueEvaluator(
         return cannotEvaluate(expr, this)
     }
 
-    /**
-     * Tries to compute the constant value of a node based on its [Node.prevDFG].
-     */
+    /** Tries to compute the constant value of a node based on its [Node.prevDFG]. */
     protected open fun handlePrevDFG(node: Node, depth: Int): Any? {
         // For a reference, we are interested into its last assignment into the reference
         // denoted by the previous DFG edge. We need to filter out any self-references for READWRITE

diff --git a/...rc/main/kotlin/de/fraunhofer/aisec/cpg/graph/statements/expressions/NewArrayExpression.kt b/...rc/main/kotlin/de/fraunhofer/aisec/cpg/graph/statements/expressions/NewArrayExpression.kt
@@ -25,6 +25,7 @@
  */
 package de.fraunhofer.aisec.cpg.graph.statements.expressions
 
+import de.fraunhofer.aisec.cpg.graph.HasInitializer
 import de.fraunhofer.aisec.cpg.graph.declarations.VariableDeclaration
 import de.fraunhofer.aisec.cpg.graph.edges.Edge.Companion.propertyEqualsList
 import de.fraunhofer.aisec.cpg.graph.edges.ast.astEdgesOf
@@ -38,14 +39,14 @@ import org.neo4j.ogm.annotation.Relationship
  * combination with a [VariableDeclaration].
  */
 // TODO Merge and/or refactor with new Expression
-class NewArrayExpression : Expression() {
+class NewArrayExpression : Expression(), HasInitializer {
     @Relationship("INITIALIZER") var initializerEdge = astOptionalEdgeOf<Expression>()
 
     /**
      * The initializer of the expression, if present. Many languages, such as Java, either specify
      * [dimensions] or an initializer.
      */
-    var initializer by unwrapping(NewArrayExpression::initializerEdge)
+    override var initializer by unwrapping(NewArrayExpression::initializerEdge)
 
     /**
      * Specifies the dimensions of the array that is to be created. Many languages, such as Java,