Make Flycheck use proper dependencies in Eldev projects.

For a project to be detected, it must contain file Eldev or Eldev-local in its root directory, even if Eldev doesn’t strictly require that.

• No additional steps to be performed from the command line, not even eldev prepare. However, you might need to mark the project as trusted, use M-x customize-group flycheck-eldev RET.

• Project dependencies are seen by Flycheck in Emacs. Similarly, if a package is not declared as a dependency of your project, Flycheck will complain about unimportable features or undeclared functions.

• Everything is done on-the-fly. As you edit your project’s dependency list in its main .el file, added, removed or mistyped dependency names immediately become available to Flycheck (there might be some delays due to network, as Eldev needs to fetch them first).

• Additional test dependencies (see eldev-add-extra-dependencies) are seen from the test files, but not from the main files.

• Also checks files Eldev and Eldev-local (as long as they are byte-compilable, but this is a common Flycheck requirement). Detect wrong (eldev-…​) function calls as you type!

Download and install the package from MELPA Stable or MELPA. No further steps necessary: once the package is installed, it is active and Flycheck will detect any Eldev projects on-the-fly.

For the extension to have any effect, you need to install Eldev. If Flycheck doesn’t seem to recognize dependencies declared in a project, verify its setup (C-c ! v). Normally, you should see something like this at the top:

If the project is not trusted, customize some variables in flycheck-eldev group. This is a security feature to avoid running potentially harmful code from unknown projects. If you don’t need this precaution, set flycheck-eldev-unknown-projects to trust (it is still possible to actively blacklist individual projects after that).

If you want to deactivate the package for some reason, set variable flycheck-eldev-active to nil.