fix(utils): ignore non-json lines in fromJsonLines utility

Author: matejchalk

packages/utils/src/lib/transform.ts

@@ -114,9 +114,19 @@ export function toUnixNewlines(text: string): string {
   return platform() === 'win32' ? text.replace(/\r\n/g, '\n') : text;
 }
 
-export function fromJsonLines<T = unknown>(jsonLines: string) {
+export function fromJsonLines<T extends unknown[]>(jsonLines: string) {
   const unifiedNewLines = toUnixNewlines(jsonLines).trim();
-  return JSON.parse(`[${unifiedNewLines.split('\n').join(',')}]`) as T;
+  const invalid = Symbol('invalid json');
+  return unifiedNewLines
+    .split('\n')
+    .map(line => {
+      try {
+        return JSON.parse(line);
+      } catch {
+        return invalid;
+      }
+    })
+    .filter(line => line !== invalid) as T;
 }
 
 export function toJsonLines<T>(json: T[]) {

packages/utils/src/lib/transform.unit.test.ts

@@ -258,6 +258,17 @@ describe('JSON lines format', () => {
 
       expect(fromJsonLines(jsonLines)).toEqual([head, body]);
     });
+
+    it('should ignore non-JSON lines', () => {
+      const jsonLines = [
+        '(node:346640) [DEP0040] DeprecationWarning: The `punycode` module is deprecated. Please use a userland alternative instead.',
+        '(Use `node --trace-deprecation ...` to show where the warning was created)',
+        JSON.stringify(head),
+        JSON.stringify(body),
+      ].join('\n');
+
+      expect(fromJsonLines(jsonLines)).toEqual([head, body]);
+    });
   });
 
   describe('toJsonLines', () => {