Add git hooks

Summary

./godelw git-hooks installs a Git commit hook that ensures that all of the files in a project are formatted using ./godelw format before they are committed (requires the project to be a Git repository).

Tutorial start state

• ${GOPATH}/src/${PROJECT_PATH} exists, is the working directory and is initialized as a Git repository and Go module
• Project contains godel and godelw

Create Git commit hook

Install the Git hooks for gödel in the current project by running the following:

➜ ./godelw git-hooks

With the repository initialized and hooks installed, we start writing code. Run the following to generate the initial version of a main.go file echoes the arguments provided by the user:

➜ echo 'package main
import "fmt"
import "strings"
import "os"
func main() {
	fmt.Println(strings.Join(os.Args[1:], " "))
}' > main.go

This is valid Go that compiles and runs properly:

➜ go run main.go foo
foo

However, if we attempt to add and commit this file to the repository, it will fail:

➜ git add main.go
➜ git commit -m "Add main.go"
Unformatted files exist -- run ./godelw format to format these files:
  main.go

This is because the commit hook has determined that main.go is not formatted properly. We can run ./godelw format (this is covered in more detail in the Format section of the tutorial) to format the file and then verify that adding and committing the file works:

➜ ./godelw format
➜ git add main.go
➜ git commit -m "Add main.go"
[master d461fb7] Add main.go
 1 file changed, 11 insertions(+)
 create mode 100644 main.go

We now have a repository that contains the first version of our echgo2 program and have a commit hook that ensures that all of the code we check in for our program will be properly formatted.

Tutorial end state

• ${GOPATH}/src/${PROJECT_PATH} exists, is the working directory and is initialized as a Git repository and Go module
• Project contains godel and godelw
• Project contains main.go

Tutorial next step

Generate IDE project for GoLand

More

Hook installation

Running ./godelw git-hooks will overwrite the .git/hooks/pre-commit file (including any previous customizations).

Uninstalling the hook

The commit hook can be uninstalled by removing the generated commit hook file at .git/hooks/pre-commit.