Name several To-dos tools without a doubled s, and make every container spell its plural

A cross-project to-do list move into a project with two To-dos tools
refused with "Dest has 2 To-doss that match": the To-dos container set
no plural, so the message appended "s" to "To-dos". The container came
in with todo-moves (#976); it is fixed here, at the top of the stack,
rather than on that branch.

The container now says "To-dos tools". The fallback that appended "s"
is gone: every filingContainer spells its plural out, and a test reads
the package's source and fails on any filingContainer literal without
one, so the next container cannot fall into the same message.

Author: robzolkos

internal/commands/cards.go

@@ -2712,6 +2712,7 @@ and On hold. The command waits for Basecamp to make the copy and shows it.`,
 var cardTableContainer = filingContainer{
 	dockName: "kanban_board",
 	noun:     "card table",
+	plural:   "card tables",
 	flag:     "--to-card-table",
 	urlKind:  "card_tables",
 	urlShape: "…/card_tables/<id>",

internal/commands/filing_family.go

@@ -26,7 +26,8 @@ type filingContainer struct {
 	// dockName is the tool's name in a project's dock: "message_board".
 	dockName string
 	noun     string
-	// plural is the noun's plural when appending "s" is wrong.
+	// plural names several of them in messages: "message boards", or
+	// "To-dos tools" where appending "s" reads wrong. Every container sets it.
 	plural   string
 	flag     string
 	urlKind  string
@@ -35,13 +36,6 @@ type filingContainer struct {
 	get func(ctx context.Context, app *appctx.App, id int64) (filingTarget, error)
 }
 
-func (c filingContainer) plurals() string {
-	if c.plural != "" {
-		return c.plural
-	}
-	return output.PluralNoun(c.noun)
-}
-
 // filingTarget is the container a recording is moved or copied into.
 type filingTarget struct {
 	id    int64
@@ -148,7 +142,7 @@ func resolveFilingTarget(cmd *cobra.Command, app *appctx.App, c filingContainer,
 	}
 	if url != "" {
 		return filingTarget{}, filingURLNotFound(c.flag, c.noun, url, projectName,
-			fmt.Sprintf("Its %s: %s", c.plurals(), formatDockTools(enabled)))
+			fmt.Sprintf("Its %s: %s", c.plural, formatDockTools(enabled)))
 	}
 	switch len(named) {
 	case 0:
@@ -162,7 +156,7 @@ func resolveFilingTarget(cmd *cobra.Command, app *appctx.App, c filingContainer,
 	}
 	return filingTarget{}, output.ErrUsageHint(
 		fmt.Sprintf("%s %q is not a %s in %s", c.flag, toContainer, c.noun, projectName),
-		fmt.Sprintf("Its %s: %s", c.plurals(), formatDockTools(enabled)),
+		fmt.Sprintf("Its %s: %s", c.plural, formatDockTools(enabled)),
 	)
 }
 
@@ -214,7 +208,7 @@ func ambiguousFilingContainerError(c filingContainer, projectName string, tools
 	}
 	return &output.Error{
 		Code:    output.CodeAmbiguous,
-		Message: fmt.Sprintf("%s has %d %s that match", projectName, len(tools), c.plurals()),
+		Message: fmt.Sprintf("%s has %d %s that match", projectName, len(tools), c.plural),
 		Hint:    fmt.Sprintf("Specify one with %s <id>:\n%s", c.flag, strings.Join(lines, "\n")),
 	}
 }

internal/commands/filing_family_test.go

@@ -4,8 +4,13 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/token"
 	"io"
 	"net/http"
+	"os"
+	"path/filepath"
 	"regexp"
 	"slices"
 	"strconv"
@@ -142,6 +147,7 @@ func boardsContainer() filingContainer {
 	return filingContainer{
 		dockName: "message_board",
 		noun:     "message board",
+		plural:   "message boards",
 		flag:     "--to-board",
 		urlKind:  "message_boards",
 		urlShape: "…/message_boards/<id>",
@@ -164,6 +170,44 @@ func resolveTestTarget(t *testing.T, transport *familyTransport, toProject, toCo
 	return target, err
 }
 
+// Appending "s" to a container's noun once named a project's To-dos tools
+// "To-doss", so every filingContainer literal spells its plural out. The test
+// reads the package's source, so it covers containers no test resolves.
+func TestEveryFilingContainerNamesItsPlural(t *testing.T) {
+	files, err := filepath.Glob("*.go")
+	require.NoError(t, err)
+	fset := token.NewFileSet()
+	var containers int
+	for _, name := range files {
+		src, err := os.ReadFile(name)
+		require.NoError(t, err)
+		file, err := parser.ParseFile(fset, name, src, 0)
+		require.NoError(t, err)
+		ast.Inspect(file, func(n ast.Node) bool {
+			lit, ok := n.(*ast.CompositeLit)
+			if !ok {
+				return true
+			}
+			if typ, ok := lit.Type.(*ast.Ident); !ok || typ.Name != "filingContainer" {
+				return true
+			}
+			containers++
+			named := slices.ContainsFunc(lit.Elts, func(e ast.Expr) bool {
+				kv, ok := e.(*ast.KeyValueExpr)
+				if !ok {
+					return false
+				}
+				key, ok := kv.Key.(*ast.Ident)
+				value, isString := kv.Value.(*ast.BasicLit)
+				return ok && key.Name == "plural" && isString && value.Value != `""`
+			})
+			assert.True(t, named, "%s: a filingContainer sets plural", fset.Position(lit.Pos()))
+			return true
+		})
+	}
+	assert.GreaterOrEqual(t, containers, 7, "the scan finds every family's container")
+}
+
 func dockTransport(dock string) *familyTransport {
 	return &familyTransport{gets: map[string]string{
 		"/projects":     filingProjects,

internal/commands/messages.go

@@ -1121,6 +1121,7 @@ func messageFamily() filingFamily {
 		into: filingContainer{
 			dockName: "message_board",
 			noun:     "message board",
+			plural:   "message boards",
 			flag:     "--to-board",
 			urlKind:  "message_boards",
 			urlShape: "…/message_boards/<id>",

internal/commands/schedule.go

@@ -987,6 +987,7 @@ func scheduleEntryFamily() filingFamily {
 		into: filingContainer{
 			dockName: "schedule",
 			noun:     "schedule",
+			plural:   "schedules",
 			flag:     "--to-schedule",
 			urlKind:  "schedules",
 			urlShape: "…/schedules/<id>",

internal/commands/todolists.go

@@ -1183,6 +1183,7 @@ func readFiledTodolist(app *appctx.App, sourceID int64) func(context.Context, in
 var todosetContainer = filingContainer{
 	dockName: "todoset",
 	noun:     "To-dos",
+	plural:   "To-dos tools",
 	flag:     "--to-todoset",
 	urlKind:  "todosets",
 	urlShape: "…/todosets/<id>",

internal/commands/todolists_filing_test.go

@@ -32,6 +32,7 @@ func TestTodolistsMoveToAProjectWithSeveralTodosetsIsAmbiguous(t *testing.T) {
 	e := requireUsageRefusal(t, run, transport)
 
 	assert.Equal(t, output.CodeAmbiguous, e.Code)
+	assert.Equal(t, "Dest has 2 To-dos tools that match", e.Message)
 	assert.Contains(t, e.Hint, "--to-todoset")
 	assert.Contains(t, e.Hint, "900  To-dos")
 	assert.Contains(t, e.Hint, "950  To-dos")