flow like the river

VISUALIZACION/node_modules/graphql/utilities/getOperationAST.js.flow

@@ -0,0 +1,31 @@
+// @flow strict
+import type { DocumentNode, OperationDefinitionNode } from '../language/ast';
+import { Kind } from '../language/kinds';
+
+/**
+ * Returns an operation AST given a document AST and optionally an operation
+ * name. If a name is not provided, an operation is only returned if only one is
+ * provided in the document.
+ */
+export function getOperationAST(
+  documentAST: DocumentNode,
+  operationName?: ?string,
+): ?OperationDefinitionNode {
+  let operation = null;
+  for (const definition of documentAST.definitions) {
+    if (definition.kind === Kind.OPERATION_DEFINITION) {
+      if (operationName == null) {
+        // If no operation name was provided, only return an Operation if there
+        // is one defined in the document. Upon encountering the second, return
+        // null.
+        if (operation) {
+          return null;
+        }
+        operation = definition;
+      } else if (definition.name?.value === operationName) {
+        return definition;
+      }
+    }
+  }
+  return operation;
+}