Cover shared debug binding composition

docs/roadmap/implementation.md

@@ -1,6 +1,6 @@
 # Shared debug binding implementation plan
 
-Status: in progress; Stages 1–3 complete.
+Status: in progress; Stages 1–4 complete.
 Baseline: `6727d22ce6e1ac668b56a3e6d8fa5f7a06e54d88`.
 Execution audience: Luna coding agent.
 
@@ -185,6 +185,12 @@ parse, without changing unrelated input indexes, grammar, or failure handling.
 
 ## Stage 4 — Preserve composition, defaults, and alias behavior
 
+**Complete.** Existing capture and rename machinery retains the boolean
+identity and requiredness without production changes. Focused public tests
+cover true defaults, explicit false, direct and captured requiredness, both
+application methods, renaming in both directions, and an alias to the local
+short spelling; capture and alias tests pass offline with Go 1.27.0.
+
 Primary files: [flag_values.go](../../flag_values.go),
 [binding.go](../../binding.go), [flag_aliases.go](../../flag_aliases.go).
 

shared_debug_external_test.go

@@ -2,6 +2,7 @@ package commandkit_test
 
 import (
 	"context"
+	"errors"
 	"io"
 	"sync"
 	"testing"
@@ -122,3 +123,83 @@ func TestSharedDebugBindingAndReportingMode(t *testing.T) {
 		t.Fatalf("operand after terminator: %#v %#v mode=%v", got, received, mode)
 	}
 }
+
+func TestSharedDebugCapturedDefaultsAndRequiredness(t *testing.T) {
+	type inner struct{ debug commandkit.Supplied[bool] }
+	type outer struct{ flags commandkit.FlagValues[inner] }
+	for _, required := range []bool{false, true} {
+		flag := commandkit.BoolFlag(commandkit.FlagMeta{Name: "debug", Short: "d", Required: required}, true, func(i *inner, v commandkit.Supplied[bool]) { i.debug = v })
+		captured := commandkit.CaptureFlags([]commandkit.Flag[inner]{flag}, func(i *outer) *commandkit.FlagValues[inner] { return &i.flags })
+		var applied, supplied inner
+		var applyErr error
+		var mode commandkit.ReportingMode
+		cmd := commandkit.NewCommand(commandkit.CommandSpec[outer]{Name: "run", Flags: captured, Run: func(inv commandkit.Invocation, i outer) commandkit.Outcome {
+			mode = inv.ReportingMode()
+			applied = inner{}
+			supplied = inner{debug: commandkit.Supplied[bool]{Value: true, Set: true}}
+			applyErr = i.flags.ApplyTo(&applied, flag)
+			if err := i.flags.ApplySuppliedTo(&supplied, flag); err != nil && applyErr == nil {
+				applyErr = err
+			}
+			return commandkit.Success()
+		}})
+		app, err := commandkit.New(commandkit.Identity{Name: "example"}, cmd, commandkit.FlagAliasFor("run", "-x", "-d"))
+		if err != nil {
+			t.Fatal(err)
+		}
+		result := app.Execute(context.Background(), []string{"run"}, commandkit.Streams{})
+		if result.Kind != commandkit.OutcomeSuccess || mode != commandkit.ReportingModeOrdinary {
+			t.Fatalf("omission=%#v mode=%v", result, mode)
+		}
+		if required {
+			if !errors.Is(applyErr, commandkit.ErrFlagInput) {
+				t.Fatalf("missing required: %v", applyErr)
+			}
+		} else if applyErr != nil || !applied.debug.Value || applied.debug.Set || !supplied.debug.Value || !supplied.debug.Set {
+			t.Fatalf("defaults=%#v %#v %v", applied, supplied, applyErr)
+		}
+		result = app.Execute(context.Background(), []string{"run", "-x=false"}, commandkit.Streams{})
+		if result.Kind != commandkit.OutcomeSuccess || applyErr != nil || applied.debug.Value || !applied.debug.Set || supplied.debug.Value || !supplied.debug.Set || mode != commandkit.ReportingModeOrdinary {
+			t.Fatalf("false=%#v %#v %#v mode=%v err=%v", result, applied, supplied, mode, applyErr)
+		}
+	}
+}
+
+func TestSharedDebugDirectRequiredAndRenamedBinding(t *testing.T) {
+	type input struct{ debug commandkit.Supplied[bool] }
+	var got input
+	var mode commandkit.ReportingMode
+	original := commandkit.BoolFlag(commandkit.FlagMeta{Name: "debug", Required: true}, true, func(i *input, v commandkit.Supplied[bool]) { i.debug = v })
+	required := commandkit.NewCommand(commandkit.CommandSpec[input]{Name: "required", Flags: []commandkit.Flag[input]{original}, Run: func(inv commandkit.Invocation, i input) commandkit.Outcome {
+		got = i
+		mode = inv.ReportingMode()
+		return commandkit.Success()
+	}})
+	renamed := commandkit.NewCommand(commandkit.CommandSpec[input]{Name: "renamed", Flags: []commandkit.Flag[input]{commandkit.RenameFlag(original, "trace")}, Run: func(inv commandkit.Invocation, i input) commandkit.Outcome {
+		got = i
+		mode = inv.ReportingMode()
+		return commandkit.Success()
+	}})
+	ordinary := commandkit.BoolFlag(commandkit.FlagMeta{Name: "local"}, false, func(i *input, v commandkit.Supplied[bool]) { i.debug = v })
+	attached := commandkit.NewCommand(commandkit.CommandSpec[input]{Name: "attached", Flags: []commandkit.Flag[input]{commandkit.RenameFlag(ordinary, "debug")}, Run: func(inv commandkit.Invocation, i input) commandkit.Outcome {
+		got = i
+		mode = inv.ReportingMode()
+		return commandkit.Success()
+	}})
+	app, err := commandkit.New(commandkit.Identity{Name: "example"}, required, renamed, attached)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if r := app.Execute(context.Background(), []string{"required"}, commandkit.Streams{}); r.Kind != commandkit.OutcomeUsage {
+		t.Fatalf("required omission=%#v", r)
+	}
+	if r := app.Execute(context.Background(), []string{"required", "--debug=false"}, commandkit.Streams{}); r.Kind != commandkit.OutcomeSuccess || got.debug.Value || !got.debug.Set || mode != commandkit.ReportingModeOrdinary {
+		t.Fatalf("explicit false=%#v %#v", r, got)
+	}
+	if r := app.Execute(context.Background(), []string{"renamed", "--trace=false", "--debug"}, commandkit.Streams{}); r.Kind != commandkit.OutcomeSuccess || got.debug.Value || !got.debug.Set || mode != commandkit.ReportingModeDebug {
+		t.Fatalf("renamed=%#v %#v mode=%v", r, got, mode)
+	}
+	if r := app.Execute(context.Background(), []string{"attached", "--debug"}, commandkit.Streams{}); r.Kind != commandkit.OutcomeSuccess || !got.debug.Value || !got.debug.Set || mode != commandkit.ReportingModeDebug {
+		t.Fatalf("renamed to debug=%#v %#v mode=%v", r, got, mode)
+	}
+}