README.adoc

@@ -9,8 +9,6 @@ The project also contains reusable Go packages with a Brother QL-series USB
 printer driver and a simple BDF bitmap font renderer, as well as a few related
 utilities for previewing, printing and debugging.
 
-image::sklad.png[align="center"]
-
 Building and Running
 --------------------
 Build dependencies: Go +

cmd/sklad/container.tmpl

@@ -12,8 +12,6 @@
 <p>Chyba: Řadu u neprázdných obalů nelze měnit.
 {{ else if .ErrorCannotChangeNumber }}
 <p>Chyba: Číslo obalu v řadě nelze měnit.
-{{ else if .ErrorWouldContainItself }}
-<p>Chyba: Obal by obsahoval sám sebe.
 {{ else if .ErrorContainerInUse }}
 <p>Chyba: Obal se používá.
 {{ else if .Error }}
@@ -29,7 +27,7 @@
 	<small>&laquo; <a href="container?id={{ . }}">{{ . }}</a></small>
 {{ end }}
 	</h2>
-	<form method=post action="label?id={{ .Container.Id }}" target=_blank>
+	<form method=post action="label?id={{ .Container.Id }}">
 	<input type=submit value="Vytisknout štítek">
 	</form>
 	<form method=post action="container?id={{ .Container.Id }}&amp;remove">
@@ -101,7 +99,7 @@
 	<small>&laquo; <a href="container?id={{ . }}">{{ . }}</a></small>
 {{ end }}
 	</h3>
-	<form method=post action="label?id={{ .Id }}" target=_blank>
+	<form method=post action="label?id={{ .Id }}">
 	<input type=submit value="Vytisknout štítek">
 	</form>
 	<form method=post action="container?id={{ .Id }}&amp;remove">

cmd/sklad/db.go

@@ -163,7 +163,6 @@ var errNoSuchContainer = errors.New("no such container")
 var errCannotChangeSeriesNotEmpty = errors.New(
 	"cannot change the series of a non-empty container")
 var errCannotChangeNumber = errors.New("cannot change the number")
-var errWouldContainItself = errors.New("container would contain itself")
 var errContainerInUse = errors.New("container is in use")
 
 // Find and filter out the container in O(n).
@@ -205,27 +204,19 @@ func dbContainerCreate(c *Container) error {
 }
 
 func dbContainerUpdate(c *Container, updated Container) error {
-	newID := updated.Id()
+	newId := updated.Id()
 	if updated.Series != c.Series && len(c.Children()) > 0 {
 		return errCannotChangeSeriesNotEmpty
 	}
 	if updated.Number != c.Number {
 		return errCannotChangeNumber
 	}
-	if _, ok := indexContainer[newID]; ok && newID != c.Id() {
+	if _, ok := indexContainer[newId]; ok && newId != c.Id() {
 		return errContainerAlreadyExists
 	}
 	if updated.Parent != c.Parent {
-		// Relying on the invariant that we can't change the ID
-		// of a non-empty container.
-		for pv := &updated; pv.Parent != ""; pv = indexContainer[pv.Parent] {
-			if pv.Parent == updated.Id() {
-				return errWouldContainItself
-			}
-		}
-
 		indexChildren[c.Parent] = filterContainer(indexChildren[c.Parent], c)
-		indexChildren[newID] = append(indexChildren[newID], c)
+		indexChildren[newId] = append(indexChildren[newId], c)
 	}
 	*c = updated
 	return dbCommit()

cmd/sklad/main.go

@@ -130,7 +130,6 @@ func handleContainer(w http.ResponseWriter, r *http.Request) {
 		ErrorNoSuchContainer            bool
 		ErrorCannotChangeSeriesNotEmpty bool
 		ErrorCannotChangeNumber         bool
-		ErrorWouldContainItself         bool
 		ErrorContainerInUse             bool
 		Container                       *Container
 		Children                        []*Container
@@ -142,7 +141,6 @@ func handleContainer(w http.ResponseWriter, r *http.Request) {
 		ErrorNoSuchContainer:            err == errNoSuchContainer,
 		ErrorCannotChangeSeriesNotEmpty: err == errCannotChangeSeriesNotEmpty,
 		ErrorCannotChangeNumber:         err == errCannotChangeNumber,
-		ErrorWouldContainItself:         err == errWouldContainItself,
 		ErrorContainerInUse:             err == errContainerInUse,
 		Container:                       container,
 		Children:                        children,