c2cpg: handle method bodies for lambdas (#3523)

We only generated stubs for CPP lambdas. This PR fixes that. Fixes: #3522
joernio · Aug 20, 2023 · d94fdcd · d94fdcd
1 parent a9338ea
commit d94fdcd
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Showing 3 changed files with 18 additions and 12 deletions.
diff --git a/...li/frontends/c2cpg/src/main/scala/io/joern/c2cpg/astcreation/AstForFunctionsCreator.scala b/...li/frontends/c2cpg/src/main/scala/io/joern/c2cpg/astcreation/AstForFunctionsCreator.scala
@@ -51,7 +51,7 @@ trait AstForFunctionsCreator(implicit withSchemaValidation: ValidationMode) { th
     Ast(functionBinding).withBindsEdge(parentNode, functionBinding).withRefEdge(functionBinding, method)
   }
 
-  private def parameters(funct: IASTNode): Seq[IASTNode] = funct match {
+  private def parameters(functionNode: IASTNode): Seq[IASTNode] = functionNode match {
     case arr: IASTArrayDeclarator       => parameters(arr.getNestedDeclarator)
     case decl: CPPASTFunctionDeclarator => decl.getParameters.toIndexedSeq ++ parameters(decl.getNestedDeclarator)
     case decl: CASTFunctionDeclarator   => decl.getParameters.toIndexedSeq ++ parameters(decl.getNestedDeclarator)
@@ -64,7 +64,7 @@ trait AstForFunctionsCreator(implicit withSchemaValidation: ValidationMode) { th
   }
 
   @tailrec
-  private def isVariadic(funct: IASTNode): Boolean = funct match {
+  private def isVariadic(functionNode: IASTNode): Boolean = functionNode match {
     case decl: CPPASTFunctionDeclarator            => decl.takesVarArgs()
     case decl: CASTFunctionDeclarator              => decl.takesVarArgs()
     case defn: IASTFunctionDefinition              => isVariadic(defn.getDeclarator)
@@ -114,10 +114,14 @@ trait AstForFunctionsCreator(implicit withSchemaValidation: ValidationMode) { th
 
     scope.popScope()
 
-    val stubAst =
-      methodStubAst(methodNode_, parameterNodes, newMethodReturnNode(lambdaExpression, registerType(returnType)))
+    val astForLambda = methodAst(
+      methodNode_,
+      parameterNodes.map(Ast(_)),
+      astForMethodBody(Option(lambdaExpression.getBody)),
+      newMethodReturnNode(lambdaExpression, registerType(returnType))
+    )
     val typeDeclAst = createFunctionTypeAndTypeDecl(lambdaExpression, methodNode_, name, fullname, signature)
-    Ast.storeInDiffGraph(stubAst.merge(typeDeclAst), diffGraph)
+    Ast.storeInDiffGraph(astForLambda.merge(typeDeclAst), diffGraph)
 
     Ast(methodRefNode(lambdaExpression, code, fullname, methodNode_.astParentFullName))
   }

diff --git a/...i/frontends/c2cpg/src/main/scala/io/joern/c2cpg/astcreation/AstForStatementsCreator.scala b/...i/frontends/c2cpg/src/main/scala/io/joern/c2cpg/astcreation/AstForStatementsCreator.scala
@@ -16,7 +16,11 @@ trait AstForStatementsCreator(implicit withSchemaValidation: ValidationMode) { t
   import io.joern.c2cpg.astcreation.AstCreatorHelper.OptionSafeAst
 
   protected def astForBlockStatement(blockStmt: IASTCompoundStatement, order: Int = -1): Ast = {
-    val node = blockNode(blockStmt, Defines.empty, registerType(Defines.voidTypeName)).order(order).argumentIndex(order)
+    val code      = nodeSignature(blockStmt)
+    val blockCode = if (code == "{}" || code.isEmpty) Defines.empty else code
+    val node = blockNode(blockStmt, blockCode, registerType(Defines.voidTypeName))
+      .order(order)
+      .argumentIndex(order)
     scope.pushNewScope(node)
     var currOrder = 1
     val childAsts = blockStmt.getStatements.flatMap { stmt =>

diff --git a/...n-cli/frontends/c2cpg/src/test/scala/io/joern/c2cpg/passes/ast/AstCreationPassTests.scala b/...n-cli/frontends/c2cpg/src/test/scala/io/joern/c2cpg/passes/ast/AstCreationPassTests.scala
@@ -98,13 +98,9 @@ class AstCreationPassTests extends AbstractPassTest {
     "be correct for simple lambda expressions" in AstFixture(
       """
         |auto x = [] (int a, int b) -> int
-        |{
-        |    return a + b;
-        |};
+        | { return a + b; };
         |auto y = [] (string a, string b) -> string
-        |{
-        |    return a + b;
-        |};
+        | { return a + b; };
         |""".stripMargin,
       "test.cpp"
     ) { cpg =>
@@ -129,12 +125,14 @@ class AstCreationPassTests extends AbstractPassTest {
         l1.name shouldBe lambda1FullName
         l1.code should startWith("[] (int a, int b) -> int")
         l1.signature shouldBe "int anonymous_lambda_0 (int,int)"
+        l1.body.code shouldBe "{ return a + b; }"
       }
 
       inside(cpg.method.fullNameExact(lambda2FullName).l) { case List(l2) =>
         l2.name shouldBe lambda2FullName
         l2.code should startWith("[] (string a, string b) -> string")
         l2.signature shouldBe "string anonymous_lambda_1 (string,string)"
+        l2.body.code shouldBe "{ return a + b; }"
       }
 
       inside(cpg.typeDecl(NamespaceTraversal.globalNamespaceName).head.bindsOut.l) {