completion: display descriptions next to choices

Use go-opt v2 new completion API which returns items descriptions along
with their text values.

Display the descriptions after the items separated by two spaces. Wrap
the descriptions in parentheses to better indicate that they are not
part of the completion choices. Limit the description length to 80
characters to avoid display issues.

Add a new style object completion_description in stylesets. By default,
the object will be rendered with a dimmed terminal attribute. Update all
stylesets and documentation accordingly.

Implements: https://todo.sr.ht/~rjarry/aerc/271
Link: https://git.sr.ht/~rjarry/go-opt/commit/ebeb82538395a
Changelog-added: Command completion now displays descriptions next
 to completion items.
Changelog-added: New `completion_description` style object in style
 sets used for rendering completion item descriptions.
Signed-off-by: Robin Jarry <robin@jarry.cc>
Tested-by: Bojan Gabric <bojan@bojangabric.com>
Tested-by: Jason Cox <me@jasoncarloscox.com>
Acked-by: Tim Culverhouse <tim@timculverhouse.com>

1 files changed, 10 insertions, 8 deletions

diff --git a/completer/completer.go b/completer/completer.go
index 5a5dea10..c5b61528 100644
--- a/completer/completer.go
+++ b/completer/completer.go
@@ -13,7 +13,7 @@ import (
 
 	"git.sr.ht/~rjarry/aerc/lib/format"
 	"git.sr.ht/~rjarry/aerc/lib/log"
-	"git.sr.ht/~rjarry/go-opt"
+	"git.sr.ht/~rjarry/go-opt/v2"
 )
 
 // A Completer is used to autocomplete text inputs based on the configured
@@ -31,7 +31,7 @@ type Completer struct {
 
 // A CompleteFunc accepts a string to be completed and returns a slice of
 // completions candidates with a prefix to prepend to the chosen candidate
-type CompleteFunc func(string) ([]string, string)
+type CompleteFunc func(string) ([]opt.Completion, string)
 
 // New creates a new Completer with the specified address book command.
 func New(addressBookCmd string, errHandler func(error)) *Completer {
@@ -51,11 +51,11 @@ func (c *Completer) ForHeader(h string) CompleteFunc {
 			return nil
 		}
 		// wrap completeAddress in an error handler
-		return func(s string) ([]string, string) {
+		return func(s string) ([]opt.Completion, string) {
 			completions, prefix, err := c.completeAddress(s)
 			if err != nil {
 				c.handleErr(err)
-				return []string{}, ""
+				return []opt.Completion{}, ""
 			}
 			return completions, prefix
 		}
@@ -80,7 +80,7 @@ var tooManyLines = fmt.Errorf("returned more than %d lines", maxCompletionLines)
 // completeAddress uses the configured address book completion command to fetch
 // completions for the specified string, returning a slice of completions and
 // a prefix to be prepended to the selected completion, or an error.
-func (c *Completer) completeAddress(s string) ([]string, string, error) {
+func (c *Completer) completeAddress(s string) ([]opt.Completion, string, error) {
 	prefix, candidate := c.parseAddress(s)
 	cmd, err := c.getAddressCmd(candidate)
 	if err != nil {
@@ -156,9 +156,9 @@ func (c *Completer) getAddressCmd(s string) (*exec.Cmd, error) {
 // must consist of tab-delimited fields. Only the first field (the email
 // address field) is required, the second field (the contact name) is optional,
 // and subsequent fields are ignored.
-func readCompletions(r io.Reader) ([]string, error) {
+func readCompletions(r io.Reader) ([]opt.Completion, error) {
 	buf := bufio.NewReader(r)
-	completions := []string{}
+	var completions []opt.Completion
 	for i := 0; i < maxCompletionLines; i++ {
 		line, err := buf.ReadString('\n')
 		if errors.Is(err, io.EOF) {
@@ -180,7 +180,9 @@ func readCompletions(r io.Reader) ([]string, error) {
 		if len(parts) > 1 {
 			addr.Name = strings.TrimSpace(parts[1])
 		}
-		completions = append(completions, format.AddressForHumans(addr))
+		completions = append(completions, opt.Completion{
+			Value: format.AddressForHumans(addr),
+		})
 	}
 	return completions, tooManyLines
 }