[BUG] `npm search module_does_not_exist --json` returns invalid JSON

[dionjwa]

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

npm search module_does_not_exist --json

returns invalid JSON

Expected Behavior

npm search module_does_not_exist --json

should valid JSON: []

Steps To Reproduce

npm i -g npm@7.23.0
npm search lodash --json

Outputs valid JSON

npm i -g npm@7.23.0
npm search lodash_does_not_exist --json

Outputs just ]
which is not valid json so e.g. npm search lodash_does_not_exist --json | jq fails.

Environment

• OS: Linux 5.10.47-linuxkit archive: committable offline dependency archive #1 SMP x86_64 Linux
• Node: v14.17.5
• npm: 7.23.0