With the latest CLI (sfdx-cli/6.52.2-c6cdc99881 (darwin-x64) node-v8.9.4) i have observed that the mdapi:source convert fails when the package has the lwc bundle .
The salesforcedx plugin version is salesforcedx 45.1.2
Steps to reproduce
Create an unmanaged package in Developer Edition org with lwc bundle and retrieve src by package name or clone the git repo here https://github.com/msrivastav13/mdapi-convert-lwc-bug.git
Source convert it using below
sfdx force:mdapi:convert -r ./mdapiout -d force-app
The error in the console is as below
An error was encountered processing path: /Users/mohith/Desktop/Projects/DemoApplication/mdapio ut/src/lwc//.html.
Here is the complete log for more info.
Anybody else facing this or it's just me ?