When the Unified Agent identifies a package.json file, it tries to determine whether it is an NPM or a yarn project based on the relevant lock file.
If yarn.lock is identified, the yarn resolution is performed. In addition, if the npm.runPreStep is set, theyarn installis executed.
If package-lock.json is identified, the NPM resolution is performed. In addition, if the npm.runPreStep is set, then npm installis executed.
Only if both lock files are found or missing, the Unified Agent will use the npm.yarnProject parameter to determine which pre-step and/or resolution to perform.
For more information, see the Unified Agent Configuration Parameters page.