complete/doc.go

135 lines
3.8 KiB
Go

/*
Package complete is everything for bash completion and Go.
Writing bash completion scripts is a hard work, usually done in the bash scripting language.
This package provides:
* A library for bash completion for Go programs.
* A tool for writing bash completion script in the Go language. For any Go or non Go program.
* Bash completion for the `go` command line (See ./gocomplete).
* Library for bash-completion enabled flags (See ./compflag).
* Enables an easy way to install/uninstall the completion of the command.
The library and tools are extensible such that any program can add its one logic, completion types
or methologies.
Go Command Bash Completion
./gocomplete is the script for bash completion for the `go` command line. This is an example
that uses the `complete` package on the `go` command - the `complete` package can also be used to
implement any completions, see #usage.
Install:
1. Type in your shell:
go get -u github.com/posener/complete/v2/gocomplete
COMP_INSTALL=1 gocomplete
2. Restart your shell
Uninstall by `COMP_UNINSTALL=1 gocomplete`
Features:
- Complete `go` command, including sub commands and flags.
- Complete packages names or `.go` files when necessary.
- Complete test names after `-run` flag.
Complete Package
Supported shells:
- [x] bash
- [x] zsh
- [x] fish
The installation of completion for a command line tool is done automatically by this library by
running the command line tool with the `COMP_INSTALL` environment variable set. Uninstalling the
completion is similarly done by the `COMP_UNINSTALL` environment variable.
For example, if a tool called `my-cli` uses this library, the completion can install by running
`COMP_INSTALL=1 my-cli`.
Usage
Add bash completion capabilities to any Go program. See ./example/command.
import (
"flag"
"github.com/posener/complete/v2"
"github.com/posener/complete/v2/predict"
)
var (
// Add variables to the program.
name = flag.String("name", "", "")
something = flag.String("something", "", "")
nothing = flag.String("nothing", "", "")
)
func main() {
// Create the complete command.
// Here we define completion values for each flag.
cmd := &complete.Command{
Flags: map[string]complete.Predictor{
"name": predict.Set{"foo", "bar", "foo bar"},
"something": predict.Something,
"nothing": predict.Nothing,
},
}
// Run the completion - provide it with the binary name.
cmd.Complete("my-program")
// Parse the flags.
flag.Parse()
// Program logic...
}
This package also enables to complete flags defined by the standard library `flag` package.
To use this feature, simply call `complete.CommandLine` before `flag.Parse`. (See ./example/stdlib).
import (
"flag"
+ "github.com/posener/complete/v2"
)
var (
// Define flags here...
foo = flag.Bool("foo", false, "")
)
func main() {
// Call command line completion before parsing the flags - provide it with the binary name.
+ complete.CommandLine("my-program")
flag.Parse()
}
If flag value completion is desired, it can be done by providing the standard library `flag.Var`
function a `flag.Value` that also implements the `complete.Predictor` interface. For standard
flag with values, it is possible to use the `github.com/posener/complete/v2/compflag` package.
(See ./example/compflag).
import (
"flag"
+ "github.com/posener/complete/v2"
+ "github.com/posener/complete/v2/compflag"
)
var (
// Define flags here...
- foo = flag.Bool("foo", false, "")
+ foo = compflag.Bool("foo", false, "")
)
func main() {
// Call command line completion before parsing the flags.
+ complete.CommandLine("my-program")
flag.Parse()
}
Instead of calling both `complete.CommandLine` and `flag.Parse`, one can call just `compflag.Parse`
which does them both.
Testing
For command line bash completion testing use the `complete.Test` function.
*/
package complete