Fixing "Invalid path" for go + cygwin git

git.go

package main

import (
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"syscall"
)

func resolve(executable, self string) (string, error) {
	path := os.Getenv("PATH")
	exts := strings.Split(os.Getenv("PATHEXT"), ";")

	for _, dir := range filepath.SplitList(path) {
		if dir != self {
			path := filepath.Join(dir, executable)
			for _, ext := range exts {
				d, err := os.Stat(path + ext)
				if err == nil && !d.IsDir() {
					return path + ext, nil
				}
			}
		}
	}
	return "", fmt.Errorf("Could not find %s in path", executable)
}

func main() {
	exe, err := resolve("git", filepath.Dir(os.Args[0]))
	if err != nil {
		fmt.Println(err.Error())
		os.Exit(127)
	}

	// Translate arguments
	args := make([]string, len(os.Args)-1)
	for i, arg := range os.Args[1:] {
		if strings.HasPrefix(strings.ToLower(arg), "c:") {
			args[i] = strings.Replace("/cygdrive/c"+arg[2:], "\\", "/", -1)
		} else {
			args[i] = arg
		}
	}

	// Setup command to pipe through
	cmd := exec.Command(exe, args...)
	cmd.Stdin = os.Stdin
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr

	// Run command
	if err := cmd.Start(); err != nil {
		fmt.Printf("Could not start %v: %v", cmd, err)
		os.Exit(127)
	}

	if err := cmd.Wait(); err != nil {
		if exiterr, ok := err.(*exec.ExitError); ok {
			if status, ok := exiterr.Sys().(syscall.WaitStatus); ok {
				os.Exit(status.ExitStatus())
			}
		}
	}
	os.Exit(0)
}

problem.md

When running go get from a Cygwin shell on Windows using git from Cygwin, you will see:

$ go get github.com/golang/example/hello
# cd .; git clone https://github.com/golang/example C:\tools\cygwin\home\friebe\devel\go\src\github.com\golang\example
Klone nach 'C:\tools\cygwin\home\friebe\devel\go\src\github.com\golang\example' ...
fatal: Invalid path '/home/friebe/C:\tools\cygwin\home\friebe\devel\go\src\github.com\golang\example': No such file or directory
package github.com/golang/example/hello: exit status 128

To fix this, place this file in ~/bin, run go build -o git.exe git.go and add $HOME/bin to the front of your $PATH environment variable.

Thank you... however when running with a -u flag I'm still getting errors:
$: go get -u github.com/AlekSi/gocoverutil

# cd c:\Users\me\go\src\github.com\AlekSi\gocoverutil; git pull --ff-only
exec: "c:\\Users\\me\\go\\src\\github.com\\AlekSi\\gocoverutil\\git.exe": file does not existpackage github.com/AlekSi/gocoverutil: exec: "c:\\Users\\me\\go\\src\\github.com\\AlekSi\\gocoverutil\\git.exe": file does not exist
$: go get github.com/AlekSi/gocoverutil
$:

Wonder if you had suggestions.

You are a legend for releasing this, spent hours trying to get this working without any luck until finding your program. Many thanks!