Rough sketch start of implementation for PackageJsonForCompilers concept. (Here, the name is esy instead of pjc).

esy seeks to support an "eject" feature, which makes PackageJsonForCompilers easy to deploy/build on hosts that don't even have node installed - they would only need make. Just copy the entire sandbox over to the host and run the makefile.

The esy command (without anything following the esy word), prints the environment for one package, taking into account variables exported by dependencies. The final goal of the esy build command is to walk the entire dependency graph, running their build commands, and running each dependency's build command in an environment computed from the esy command, for that one package.

The environments computed by esy are with respect to (sandbox root, cur package), where the sandbox root is the top level package we're building everything for, and cur package is one of the transitive dependencies. Running esy in a directory is like printing the environment as if pwd was both the sandbox root and the "currently building package".

The esy build command would walk the tree with sandbox root = topmost package, and at each node set cur package = <THIS_DEPENDENCY>, and run the build command in an environment computed based on that combination.

We'd want to generate a makefile that encodes the graph of packages, and can build everything with maximum parallelism.

Built In Commands

Run the test. The output shows the environment computed for a single package PackageA. Some errors are logged into the comments of the output.

cd tests/TestOne/PackageA
./test.sh

The output isn't actually verified yet. We should create many more similar tests, even if they don't work correctly yet.

• Populate all of the variables in pjc proposal.
• Should generate a build for all packages in makefile form.
• Implement "scope" concept as described in esy.js comments.
• Take buildTimeOnlyDependencies in order to "cut off" scope of environment variables.
• Automatically set up _build and _install directories, populate variables accordingly.

This is a fork of dependency-env which is more stable.