builtin_testfilepathexists.go

// scriptish is a library to help you port bash scripts to Golang
//
// inspired by:
//
// - http://labix.org/pipe
// - https://github.com/bitfield/script
//
// Copyright 2019-present Ganbaro Digital Ltd
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
//   * Redistributions of source code must retain the above copyright
//     notice, this list of conditions and the following disclaimer.
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//     distribution.
//
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package scriptish

import (
	"os"
)

// TestFilepathExists checks to see if the given filepath exists. If it does,
// the filepath is written to the pipeline's Stdout.
//
// It does not care what the filepath points at (file, folder, named pipe,
// and so on).
//
// It ignores the contents of the pipeline.
// It follows symbolic links.
func TestFilepathExists(filepath string, opts ...*StepOption) *SequenceStep {
	// build our Scriptish command
	return NewSequenceStep(
		func(p *Pipe) (int, error) {
			// expand our input
			expFilepath := p.Env.Expand(filepath)

			// debugging support
			Tracef("TestFilepathExists(%#v)", filepath)
			Tracef("=> TestFilepathExists(%#v)", expFilepath)

			// does the file exist?
			_, err := os.Stat(expFilepath)
			if err != nil {
				return StatusNotOkay, err
			}

			// all done
			return StatusOkay, nil
		},
		opts...,
	)
}