I’m trying to understand npm’s file discovery mechanism better. I noticed that when I run npm commands, it doesn’t just check my current folder for package.json. It seems like npm can also detect package.json files that are located in parent folders above where I’m currently working.
Can someone explain exactly how this search process works? Does npm automatically traverse up through the directory tree until it locates a package.json file?
Also wondering about the require() function - does it use similar logic when it’s trying to resolve module dependencies? And is this searching behavior something that comes from npm itself or is it actually part of the CommonJS specification?
also, those settings help avoid issues in monorepos, but if you really need to access a parent package.json, try using the --prefix flag to point to the right dir. makes things easier when managing scoped packages.
npm follows a pretty predictable pattern when searching directories. Run any npm command and it starts looking for package.json in your current directory. Can’t find one? It climbs up one level at a time until it finds package.json or hits the filesystem root. This is super handy for monorepos or complex projects where you’re buried several folders deep but still need the main package config. It stops at the first package.json it finds, so with nested projects, npm uses the closest one. require() works similarly but hunts for node_modules directories instead of package.json files. This traversal is baked right into Node.js - not tied to any spec, just how they designed module resolution to work efficiently.
Yes, npm searches for package.json files by starting in the current directory and then moving up the directory tree until it finds one or reaches the root. This behavior allows npm to locate the main package.json even when commands are run from subdirectories within larger projects.
Regarding the require() function, it follows a somewhat similar approach, as Node.js searches the node_modules directories starting from the current location and then ascends the hierarchy. This mechanism is part of Node.js and predates CommonJS, reflecting the hierarchical organization commonly used in projects.