refactor: Refactor KeyboardShortucts to simplify NavigationController (#61)

* refactor: Include key mappings in shortcuts

  By adding the key mappings directly to the shortcuts, they will
  be automatically mapped when the shortcuts are registered.

  This follows current practice in Blockly core/shortcut_items.ts.

* refactor: use Array.prototype.includes instead of .indexOf

* refactor: Save original Toolbox.prototype.onShortcut method

  … and restore it when removeShortcutHandlers is called.

* refactor: Put all KeyboardShortcuts in a dictionary object

  This obviates the need to have separate functions to register
  each of them, and makes it easy to ensure that we unregister
  all of them when disposing.

  This dictionary can be split into separate dictionaries for
  different modes / sub modes as needed in future.

Author: cpcallen

src/navigation.ts

@@ -380,7 +380,7 @@ export class Navigation {
 
     const curNode = cursor.getCurNode();
     const sourceBlock = curNode.getSourceBlock()!;
-    if (sourceBlock.id === deletedBlockId || ids.indexOf(sourceBlock.id) > -1) {
+    if (sourceBlock.id === deletedBlockId || ids.includes(sourceBlock.id)) {
       cursor.setCurNode(
         Blockly.ASTNode.createWorkspaceNode(
           workspace,
@@ -457,7 +457,7 @@ export class Navigation {
       // cursor to the workspace.
     } else if (
       block &&
-      deletedBlock.getChildren(false).indexOf(block as Blockly.BlockSvg) > -1
+      deletedBlock.getChildren(false).includes(block as Blockly.BlockSvg)
     ) {
       cursor.setCurNode(
         Blockly.ASTNode.createWorkspaceNode(
@@ -826,7 +826,7 @@ export class Navigation {
     let inferiorConnection;
 
     if (movingBlock.getRootBlock() === destBlock.getRootBlock()) {
-      if (movingBlock.getDescendants(false).indexOf(destBlock) > -1) {
+      if (movingBlock.getDescendants(false).includes(destBlock)) {
         inferiorConnection = this.getInferiorConnection(destConnection);
         if (inferiorConnection) {
           inferiorConnection.disconnect();
@@ -1119,7 +1119,7 @@ export class Navigation {
    */
   enableKeyboardAccessibility(workspace: Blockly.WorkspaceSvg) {
     if (
-      this.workspaces.indexOf(workspace) > -1 &&
+      this.workspaces.includes(workspace) &&
       !workspace.keyboardAccessibilityMode
     ) {
       workspace.keyboardAccessibilityMode = true;
@@ -1135,7 +1135,7 @@ export class Navigation {
    */
   disableKeyboardAccessibility(workspace: Blockly.WorkspaceSvg) {
     if (
-      this.workspaces.indexOf(workspace) > -1 &&
+      this.workspaces.includes(workspace) &&
       workspace.keyboardAccessibilityMode
     ) {
       workspace.keyboardAccessibilityMode = false;
@@ -1241,7 +1241,8 @@ export class Navigation {
   }
 
   /**
-   * Pastes the copied block to the marked location.
+   * Pastes the copied block to the marked location if possible or
+   * onto the workspace otherwise.
    *
    * @param copyData The data to paste into the workspace.
    * @param workspace The workspace to paste the data into.
@@ -1262,9 +1263,10 @@ export class Navigation {
   }
 
   /**
-   * Inserts the pasted block at the marked location if a compatible connection
-   * exists. If no connection has been marked, or there is not a compatible
-   * connection then the block is placed on the workspace.
+   * Inserts the pasted block at the marked location if a compatible
+   * connection exists. If no connection has been marked, or there is
+   * not a compatible connection then the block is placed on the
+   * workspace.
    *
    * @param workspace The workspace to paste the block on.
    * @param block The block to paste.