quick bugfix (#78)

src/lang/modifyAst.ts

@@ -347,6 +347,11 @@ export function splitPathAtLastIndex(pathToNode: PathToNode): {
       path: pathToNode.slice(0, -1),
       index: last,
     }
+  } else if (pathToNode.length === 0) {
+    return {
+      path: [],
+      index: -1,
+    }
   }
   return splitPathAtLastIndex(pathToNode.slice(0, -1))
 }

src/lang/queryAst.ts

@@ -157,7 +157,7 @@ export function findAllPreviousVariables(
   const { node: bodyItems } = getNodeFromPath<Program['body']>(ast, bodyPath)
 
   const variables: PrevVariable<any>[] = []
-  bodyItems.forEach((item) => {
+  bodyItems?.forEach?.((item) => {
     if (item.type !== 'VariableDeclaration' || item.end > sourceRange[0]) return
     const varName = item.declarations[0].id.name
     const varValue = programMemory?.root[varName]

src/lang/std/sketch.ts

@@ -1272,7 +1272,8 @@ export function addNewSketchLn({
   pathToNode,
 }: Omit<CreateLineFnCallArgs, 'from'>): { modifiedAst: Program } {
   const node = JSON.parse(JSON.stringify(_node))
-  const { add, updateArgs } = sketchLineHelperMap[fnName]
+  const { add, updateArgs } = sketchLineHelperMap?.[fnName] || {}
+  if (!add || !updateArgs) throw new Error('not a sketch line helper')
   const { node: varDec } = getNodeFromPath<VariableDeclarator>(
     node,
     pathToNode,