From 8dad7d14b474b2d897749db8fb90330837bb8328 Mon Sep 17 00:00:00 2001 From: Christian Banse Date: Mon, 7 Oct 2024 11:20:46 +0200 Subject: [PATCH] Make sure to move `typeObservers` from old to new node when replacing nodes (#1783) * Make sure to move `typeObservers` from old to new node when replacing nodes * Added doc for typeobservers --- .../de/fraunhofer/aisec/cpg/helpers/SubgraphWalker.kt | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/helpers/SubgraphWalker.kt b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/helpers/SubgraphWalker.kt index e5821b00d7..6aded16eb7 100644 --- a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/helpers/SubgraphWalker.kt +++ b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/helpers/SubgraphWalker.kt @@ -35,6 +35,7 @@ import de.fraunhofer.aisec.cpg.graph.declarations.RecordDeclaration import de.fraunhofer.aisec.cpg.graph.edges.ast.AstEdge import de.fraunhofer.aisec.cpg.graph.edges.collections.EdgeCollection import de.fraunhofer.aisec.cpg.graph.statements.expressions.Expression +import de.fraunhofer.aisec.cpg.graph.types.HasType import de.fraunhofer.aisec.cpg.passes.Pass import de.fraunhofer.aisec.cpg.processing.strategy.Strategy import java.lang.annotation.AnnotationFormatError @@ -349,13 +350,14 @@ object SubgraphWalker { /** * Tries to replace the [old] expression with a [new] one, given the [parent]. * - * There are two things to consider: + * There are three things to consider: * - First, this only works if [parent] is either an [ArgumentHolder] or [StatementHolder]. * Otherwise, we cannot instruct the parent to exchange the node * - Second, since exchanging the node has influence on their edges (such as EOG, DFG, etc.), we * only support a replacement very early in the pass system. To be specific, we only allow * replacement before any DFG edges are set. We are re-wiring EOG edges, but nothing else. If one * tries to replace a node with existing [Node.nextDFG] or [Node.prevDFG], we fail. + * - We also migrate [HasType.typeObservers] from the [old] to the [new] node. */ context(ContextProvider) fun SubgraphWalker.ScopedWalker.replace(parent: Node?, old: Expression, new: Expression): Boolean { @@ -391,6 +393,12 @@ fun SubgraphWalker.ScopedWalker.replace(parent: Node?, old: Expression, new: Exp new.prevEOG = oldPrevEOG new.nextEOG = oldNextEOG + // Also move over any type observers + old.typeObservers.forEach { + old.unregisterTypeObserver(it) + new.registerTypeObserver(it) + } + // Make sure to inform the walker about our change this.registerReplacement(old, new) }