nonbash.go

package main

import (
	"fmt"
	"os"
	"os/exec"
	"strings"
	"unicode"

	"mvdan.cc/sh/v3/syntax"
)

func main() {
	src, err := os.ReadFile("your-bash-script.sh")
	if err != nil {
		panic(err)
	}

	r := strings.NewReader(string(src))
	s, err := syntax.NewParser().Parse(r, "")
	if err != nil {
		panic(err)
	}

	nonKeywords := make(map[string]struct{})

	syntax.Walk(s, func(node syntax.Node) bool {
		switch x := node.(type) {
		case *syntax.Word:
			s := x.Lit()
			if !syntax.IsKeyword(s) {
				nonKeywords[s] = struct{}{}
			}
		}
		return true
	})

	for k := range nonKeywords {
		if IsLetter(k) {
			p, err := exec.LookPath(k)
			if err == nil {
				fmt.Printf("%s: %s\n", k, p)
			}
		}
	}
}

func IsLetter(s string) bool {
	for _, r := range s {
		if !unicode.IsLetter(r) {
			return false
		}
	}
	return true
}