When initially I started working on stevedore the goal was to support .dockerignore, however since ignore files follow a common implementation pattern, stevedore can be used on other types of ignore files - if they follow the common format.

Recently I was cleaning up some repositories adding canonical ignore files, copied from: github/gitignore, which is a repository holding all of the ignore files offered from GitHub, these are well maintained and very useful.

Anyway in the process of doing so, I wanted to make sure how things looked, so I the question arose, can I see what is and version control and what is not, after I had updated the .gitignore file to the version from the GitHub repository.

The challenge here was actually from my #48in28 Exercism participation, where I am pretty familiar the standard layout for some repositories since I am familiar with tooling and language, working with new languages does not come with the same familiarity, so I found it made sense to use canonical definitions, hence the use of github/gitignore.

For example for Clojure

I copied the file from github/gitignore/Clojure.gitignore to local: .gitignore. I actually made a fork (perhaps not necessary) and a clone so I could work on the local filesystem

cp /Users/jonasbn/develop/github-forks/gitignore/Clojure.gitignore .gitignore

After this I would run stevedore.

stevedore --ignorefile .gitignore --included --invertcolors

And it would inform me of the result.

.clj-kondo
.exercism
.exercism/config.json
.exercism/metadata.json
.git
.gitignore
.stevedoreignore
HELP.md
README.md
deps.edn
project.clj
src
src/leap.clj
test
test/leap_test.clj

And then the invert operation, to see what is excluded:

stevedore --ignorefile .gitignore --excluded --invertcolors
.cpcache
.cpcache/2823628308.basis
.cpcache/2823628308.cp
.cpcache/2823628308.main
.cpcache/2823628308.manifest

And I am pretty satisfied with the result.

A minor note on the above examples. The repository has a .stevedoreignore file with the following contents:

.git/

So the .git directory is excluded from the analysis.

Actually if I ask stevedore what is exluced using it's own ignore file:

stevedore --ignorefile .stevedoreignore --excluded --invertcolors

I get the following:

.git

As for the actual implementation. stevedore is written in Go and is one of the tools I am in the process of learning and stevedore became one of the exercises I assigned myself to get a proper example for learning Go.

stevedore uses github.com/sabhiram/go-gitignore.

It traverses the directory and makes string comparisons of the path against an instance of the above component.

If the path being inspected was a directory I would copy it and append a slash (/) and then check both.

var aliasedPath = path

if info.IsDir() {
    aliasedPath += "/"
}

if ignoreObject.MatchesPath(path) ||  ignoreObject.MatchesPath(aliasedPath) {

And this worked.

Suggestions for better implementations, feedback, PRs etc. most welcome, since this was applied swiftly and it worked.

stevedore can be found on GitHub.