Fix finally block executing twice on successful workflow runs (#4659)

skyvern/forge/sdk/workflow/service.py

@@ -1078,6 +1078,10 @@ class WorkflowService:
 
         else:
             blocks = top_level_blocks
+            # Exclude the finally block from normal traversal — it runs separately via _execute_finally_block_if_configured
+            finally_block_label = workflow.workflow_definition.finally_block_label
+            if finally_block_label:
+                blocks = self._strip_finally_block_references(blocks, finally_block_label)
 
         if not blocks:
             raise SkyvernException(f"No blocks found for the given block labels: {block_labels}")
@@ -1187,10 +1191,13 @@ class WorkflowService:
         is_script_run: bool,
         blocks_to_update: set[str],
     ) -> tuple[WorkflowRun, set[str]]:
+        finally_block_label = workflow.workflow_definition.finally_block_label
+        dag_blocks = workflow.workflow_definition.blocks
+        if finally_block_label:
+            dag_blocks = self._strip_finally_block_references(dag_blocks, finally_block_label)
+
         try:
-            start_label, label_to_block, default_next_map = self._build_workflow_graph(
-                workflow.workflow_definition.blocks
-            )
+            start_label, label_to_block, default_next_map = self._build_workflow_graph(dag_blocks)
         except InvalidWorkflowDefinition as exc:
             LOG.error("Workflow graph validation failed", error=str(exc), workflow_id=workflow.workflow_id)
             workflow_run = await self.mark_workflow_run_as_failed(
@@ -1628,6 +1635,34 @@ class WorkflowService:
                 error=str(e),
             )
 
+    @staticmethod
+    def _strip_finally_block_references(
+        blocks: list[BlockTypeVar],
+        finally_block_label: str,
+    ) -> list[BlockTypeVar]:
+        """Remove the finally block and nullify any edges that point to it.
+
+        This prevents _build_workflow_graph from raising InvalidWorkflowDefinition
+        when a block's next_block_label references the (now-excluded) finally block.
+        """
+        result: list[BlockTypeVar] = []
+        for block in blocks:
+            if block.label == finally_block_label:
+                continue
+            if isinstance(block, ConditionalBlock):
+                patched_branches = [
+                    branch.model_copy(update={"next_block_label": None})
+                    if branch.next_block_label == finally_block_label
+                    else branch
+                    for branch in block.branch_conditions
+                ]
+                if patched_branches != block.branch_conditions:
+                    block = block.model_copy(update={"branch_conditions": patched_branches})
+            elif block.next_block_label == finally_block_label:
+                block = block.model_copy(update={"next_block_label": None})
+            result.append(block)
+        return result
+
     def _build_workflow_graph(
         self,
         blocks: list[BlockTypeVar],