feat: warn about vars.tsv rows that can never apply

A fixed-value row whose name column matches no slot of the template,
or whose command is not template-derived, failed without a trace:
the value stopped applying and the slot went back to prompting at
run time. Both cases now surface in the startup warnings and baton
check, closing the last silent failure mode of hand-edited names.

Author: Taka-S-dev

README.md

@@ -352,7 +352,7 @@ Unlike command renames, name changes inside `vars.tsv` are not auto-repaired —
 
 - **Renaming a global** (`*` row): every `{$oldname}` reference stays literal, and the startup warning names each command and list still using it. Update the references yourself, or create the new name via **Manage vars** and let the rebase offer rewrite the values.
 - **Changing the command column** of a fixed-value row detaches the value: that slot is prompted at run time again, the row is flagged as belonging to an unknown command, and the next TUI save removes it.
-- **Changing the name column** of a fixed-value row to something that isn't a slot of the template: the value silently stops applying and the slot is prompted at run time.
+- **Changing the name column** of a fixed-value row to something that isn't a slot of the template: the value stops applying, the slot is prompted at run time again, and the startup warning flags the row.
 
 In short: rename commands in `commands.tsv`, rename variables through their references, and treat the first two columns of `vars.tsv` as addresses rather than free text.
 

internal/config/loader_test.go

@@ -240,6 +240,40 @@ func TestExampleProjectsLoad(t *testing.T) {
 
 // TestLoadProject_Warnings checks the diagnostics behind `baton check`:
 // a project wired with known mistakes reports each of them.
+// TestDiagnose_DeadVarRows checks fixed-value rows that can never apply
+// are warned about: a name column matching no slot of the template, and
+// a command column naming a command that is not template-derived. Valid
+// rows and globals stay quiet.
+func TestDiagnose_DeadVarRows(t *testing.T) {
+	cfg := model.Config{
+		Base: []model.Command{
+			{Name: "build", Cmd: "make {mode}", Dir: "{workdir}"},
+			{Name: "plain", Cmd: "echo hi"},
+		},
+		Commands: []model.Command{{Name: "as", Template: "build"}},
+	}
+	vars := map[string]string{
+		"as.workdir":  "./src",  // applies — must stay quiet
+		"as.workdirx": "./typo", // matches no slot
+		"plain.x":     "v",      // command is not template-derived
+		"root":        `C:\x`,   // global — never scoped
+	}
+
+	warnings := Diagnose(cfg, nil, nil, vars)
+	joined := strings.Join(warnings, "; ")
+	for _, want := range []string{
+		`"as.workdirx" is not a slot of template "build"`,
+		`"plain.x" has no effect`,
+	} {
+		if !strings.Contains(joined, want) {
+			t.Errorf("warnings missing %q, got %q", want, joined)
+		}
+	}
+	if len(warnings) != 2 {
+		t.Fatalf("warnings = %q, want exactly the two dead rows flagged", warnings)
+	}
+}
+
 func TestLoadProject_Warnings(t *testing.T) {
 	dir := t.TempDir()
 	tsv := "name\tgroup\tworkdir\tcmd\tshell\tslots\n" +

internal/config/project.go

@@ -147,5 +147,42 @@ func Diagnose(cfg model.Config, workflows []model.Workflow, lists map[string][]m
 	for _, name := range orphans {
 		warnings = append(warnings, "vars.tsv: values for unknown command \""+name+"\" (removed on next save)")
 	}
+	// Fixed-value rows whose command exists but that can never apply —
+	// the command is not template-derived, or the name column matches no
+	// slot of the template. Without a warning these fail silently: the
+	// value stops applying and the slot is prompted at run time.
+	var scoped []string
+	for k := range vars {
+		if strings.Contains(k, ".") {
+			scoped = append(scoped, k)
+		}
+	}
+	sort.Strings(scoped)
+	for _, k := range scoped {
+		i := strings.LastIndex(k, ".")
+		cmdName, slotName := k[:i], k[i+1:]
+		cmd, ok := cfg.FindCommand(cmdName)
+		if !ok {
+			continue // already reported as an orphan
+		}
+		if cmd.Template == "" {
+			warnings = append(warnings, "vars.tsv: \""+k+"\" has no effect (\""+cmdName+"\" is not template-derived)")
+			continue
+		}
+		tpl, ok := cfg.FindCommand(cmd.Template)
+		if !ok || tpl.Template != "" {
+			continue // the missing-template warning covers this command
+		}
+		found := false
+		for _, def := range slot.GetSlots(tpl) {
+			if def.Name == slotName {
+				found = true
+				break
+			}
+		}
+		if !found {
+			warnings = append(warnings, "vars.tsv: \""+k+"\" is not a slot of template \""+tpl.Name+"\"")
+		}
+	}
 	return warnings
 }