[patch] fix a case where [] type accessors crashed the plugin

Author: electrovir

src/printer/child-docs.ts

@@ -10,6 +10,7 @@ export function walkDoc(
     startDoc: Doc,
     /** Return something falsy to prevent walking of child docs */
     debug: boolean,
+    /** If this returns something falsy, none of the current node's children will be walked. */
     callback: (
         currentDoc: Doc,
         parents: Parents[],

src/printer/insert-new-lines.ts

@@ -50,7 +50,15 @@ function insertLinesIntoArray(
                 console.info(stringify(parentDoc));
             }
             if (childIndex !== 0) {
-                throw new Error(`${found} not at index 0 in its parent`);
+                /**
+                 * This happens in some situations which we don't want to format in this plugin,
+                 * like in type accessors:
+                 *
+                 * ```typescript
+                 * type mockType = exampleObject['property'];
+                 * ```
+                 */
+                return true;
             }
 
             const maybeBreak = parentDoc[childIndex + 2];

src/test/typescript-tests.mock.ts

@@ -34,6 +34,17 @@ export const typescriptTests: MultilineArrayTest[] = [
             multilineArraysWrapThreshold: 0,
         },
     },
+    {
+        it: 'works with type accessors',
+        code: `
+            export function doThing(
+                [
+                    data,
+                ]: Parameters<stuff['param']>,
+                thing: string,
+            ) {}
+        `,
+    },
     {
         it: 'works even if filepath is undefined GitHub Issue #18 (thank you farmerpaul)',
         code: `