ActionPathExecutables: added man descriptions

pkg/actions/os/executable.go

@@ -2,10 +2,12 @@ package os
 
 import (
 	"os"
+	"regexp"
 	"strings"
 
 	"github.com/rsteube/carapace"
 	"github.com/rsteube/carapace-bin/cmd/carapace/cmd/completers"
+	"github.com/rsteube/carapace-bin/pkg/util"
 	"github.com/rsteube/carapace/pkg/style"
 )
 
@@ -16,22 +18,27 @@ import (
 func ActionPathExecutables() carapace.Action {
 	return carapace.ActionCallback(func(c carapace.Context) carapace.Action {
 		batch := carapace.Batch()
+		manDescriptions := manDescriptions(c)
 		dirs := strings.Split(os.Getenv("PATH"), string(os.PathListSeparator))
 		for i := len(dirs) - 1; i >= 0; i-- {
-			batch = append(batch, actionDirectoryExecutables(dirs[i], c.CallbackValue))
+			batch = append(batch, actionDirectoryExecutables(dirs[i], c.CallbackValue, manDescriptions))
 		}
 		return batch.ToA()
 	})
 }
 
-func actionDirectoryExecutables(dir string, prefix string) carapace.Action {
+func actionDirectoryExecutables(dir string, prefix string, manDescriptions map[string]string) carapace.Action {
 	return carapace.ActionCallback(func(c carapace.Context) carapace.Action {
 		if files, err := os.ReadDir(dir); err == nil {
 			vals := make([]string, 0)
 			for _, f := range files {
 				if strings.HasPrefix(f.Name(), prefix) {
 					if info, err := f.Info(); err == nil && !f.IsDir() && isExecAny(info.Mode()) {
-						vals = append(vals, f.Name(), completers.Description(f.Name()), style.ForPath(dir+"/"+f.Name()))
+						description := completers.Description(f.Name())
+						if description == "" {
+							description = manDescriptions[f.Name()]
+						}
+						vals = append(vals, f.Name(), description, style.ForPath(dir+"/"+f.Name()))
 					}
 				}
 			}
@@ -44,3 +51,19 @@ func actionDirectoryExecutables(dir string, prefix string) carapace.Action {
 func isExecAny(mode os.FileMode) bool {
 	return mode&0111 != 0
 }
+
+func manDescriptions(c carapace.Context) (descriptions map[string]string) {
+	descriptions = make(map[string]string)
+	if !util.HasPathPrefix(c.CallbackValue) {
+		if output, err := c.Command("man", "--names-only", "-k", "^"+c.CallbackValue).Output(); err == nil {
+			lines := strings.Split(string(output), "\n")
+			r := regexp.MustCompile(`^(?P<name>[^ ]+) [^-]+- (?P<description>.*)$`)
+			for _, line := range lines {
+				if matches := r.FindStringSubmatch(line); len(matches) > 2 {
+					descriptions[matches[1]] = matches[2]
+				}
+			}
+		}
+	}
+	return
+}