Implement list reverse block

This commit introduces a new block to list operations that reverses the
order of input list and outputs the result as new list.

Change-Id: If22a6641a2586ecc6586ead9ea046cc119a2a9fc

appinventor/blocklyeditor/src/blocks/lists.js

@@ -349,6 +349,22 @@ Blockly.Blocks['lists_is_list'] = {
   typeblock: [{ translatedName: Blockly.Msg.LANG_LISTS_IS_LIST_TITLE_IS_LIST }]
 };
 
+Blockly.Blocks['lists_reverse'] = {
+  // Reverse the list.
+  category : 'Lists',
+  helpUrl : Blockly.Msg.LANG_LISTS_REVERSE_HELPURL,
+  init : function() {
+    this.setColour(Blockly.LIST_CATEGORY_HUE);
+    this.setOutput(true, Blockly.Blocks.Utilities.YailTypeToBlocklyType("list",Blockly.Blocks.Utilities.OUTPUT));
+    this.appendValueInput('LIST')
+      .setCheck(Blockly.Blocks.Utilities.YailTypeToBlocklyType("list",Blockly.Blocks.Utilities.INPUT))
+      .appendField(Blockly.Msg.LANG_LISTS_REVERSE_TITLE_REVERSE)
+      .appendField(Blockly.Msg.LANG_LISTS_REVERSE_INPUT_LIST);
+    this.setTooltip(Blockly.Msg.LANG_LISTS_REVERSE_TOOLTIP);
+  },
+  typeblock: [{ translatedName: Blockly.LANG_LISTS_REVERSE_TITLE_REVERSE }]
+}
+
 Blockly.Blocks['lists_to_csv_row'] = {
   // Make a csv row from list.
   category : 'Lists',

appinventor/blocklyeditor/src/generators/yail/lists.js

@@ -235,6 +235,19 @@ Blockly.Yail['lists_is_list'] = function() {
   return [ code, Blockly.Yail.ORDER_ATOMIC ];
 };
 
+Blockly.Yail['lists_reverse'] = function() {
+  // Reverse the list.
+  var argument0 = Blockly.Yail.valueToCode(this, 'LIST', Blockly.Yail.ORDER_NONE) || Blockly.Yail.emptyListCode;
+  var code = Blockly.Yail.YAIL_CALL_YAIL_PRIMITIVE + "yail-list-reverse" + Blockly.Yail.YAIL_SPACER;
+  code = code + Blockly.Yail.YAIL_OPEN_COMBINATION + Blockly.Yail.YAIL_LIST_CONSTRUCTOR + Blockly.Yail.YAIL_SPACER;
+  code = code + argument0;
+  code = code + Blockly.Yail.YAIL_SPACER + Blockly.Yail.YAIL_CLOSE_COMBINATION;
+  code = code + Blockly.Yail.YAIL_SPACER + Blockly.Yail.YAIL_QUOTE + Blockly.Yail.YAIL_OPEN_COMBINATION;
+  code = code + "list" + Blockly.Yail.YAIL_CLOSE_COMBINATION + Blockly.Yail.YAIL_SPACER;
+  code = code + Blockly.Yail.YAIL_DOUBLE_QUOTE + "reverse list" + Blockly.Yail.YAIL_DOUBLE_QUOTE + Blockly.Yail.YAIL_CLOSE_COMBINATION;
+  return [ code, Blockly.Yail.ORDER_ATOMIC ];
+};
+
 Blockly.Yail['lists_to_csv_row'] = function() {
   // Make a csv row from list.
   var argument0 = Blockly.Yail.valueToCode(this, 'LIST', Blockly.Yail.ORDER_NONE) || Blockly.Yail.emptyListCode;

appinventor/blocklyeditor/src/msg/en/_messages.js

@@ -841,6 +841,11 @@ Blockly.Msg.en.switch_language_to_english = {
     Blockly.Msg.LANG_LISTS_IS_LIST_INPUT_THING = 'thing';
     Blockly.Msg.LANG_LISTS_IS_LIST_TOOLTIP = 'Tests if something is a list.';
 
+    Blockly.Msg.LANG_LISTS_REVERSE_HELPURL = '/reference/blocks/lists.html#reverse';
+    Blockly.Msg.LANG_LISTS_REVERSE_TITLE_REVERSE = 'reverse list';
+    Blockly.Msg.LANG_LISTS_REVERSE_INPUT_LIST = 'list';
+    Blockly.Msg.LANG_LISTS_REVERSE_TOOLTIP = 'Reverses the order of input list and returns it as a new list.';
+
     Blockly.Msg.LANG_LISTS_TO_CSV_ROW_HELPURL = '/reference/blocks/lists.html#listtocsvrow';
     Blockly.Msg.LANG_LISTS_TO_CSV_ROW_TITLE_TO_CSV = 'list to csv row';
     Blockly.Msg.LANG_LISTS_TO_CSV_ROW_INPUT_LIST = 'list';

appinventor/blocklyeditor/src/versioning.js

@@ -1774,7 +1774,10 @@ Blockly.Versioning.AllUpgradeMaps =
     22: "noUpgrade",
 
     // AI2: Added Bitwise Blocks
-    23: "noUpgrade"
+    23: "noUpgrade",
+
+    // AI2: In BLOCKS_LANGUAGE_VERSION 24, added List Reverse Block
+    24: "noUpgrade"
 
 
   }, // End Language upgraders

appinventor/buildserver/src/com/google/appinventor/buildserver/resources/runtime.scm

@@ -1886,6 +1886,7 @@ Block name               Kawa implementation
 - remove list item        (yail-list-remove-item! yail-list index)
 - length of list          (yail-list-length yail-list)
 - copy list               (yail-list-copy list)
+- reverse list            (yail-list-reverse list)
 - list to csv row         (yail-list-to-csv-row list)
 - list to csv table       (yail-list-to-csv-table list)
 - list from csv row       (yail-list-from-csv-row text)
@@ -1980,6 +1981,13 @@ list, use the make-yail-list constructor with no arguments.
         ((not (pair? yl)) yl)
         (else (YailList:makeList (map yail-list-copy (yail-list-contents yl))))))
 
+;;; does a shallow copy of the yail list yl with its order reversed.
+;;; yl should be a YailList
+(define (yail-list-reverse yl)
+  (if (not (yail-list? yl))
+    (signal-runtime-error "Argument value to \"reverse list\" must be a list" "Expecting list")
+    (insert-yail-list-header (reverse (yail-list-contents yl)))))
+
 ;;; converts a yail list to a CSV-formatted table and returns the text.
 ;;; yl should be a YailList, each element of which is a YailList as well.
 ;;; inner list elements are sanitized

appinventor/components/src/com/google/appinventor/components/common/YaVersion.java

@@ -444,8 +444,10 @@ public class YaVersion {
   // - NOTIFIER_COMPONENT_VERSION was incremented to 6
   // For YOUNG_ANDROID_VERSION 178:
   // - CLOCK_COMPONENT_VERSION was incremented to 4
+  // For YOUNG_ANDROID_VERISON 179:
+  // - BLOCKS_LANGUAGE_VERSION was incremented to 24
 
-  public static final int YOUNG_ANDROID_VERSION = 177;
+  public static final int YOUNG_ANDROID_VERSION = 179;
 
   // ............................... Blocks Language Version Number ...............................
 
@@ -511,8 +513,10 @@ public class YaVersion {
   // - Break block was added.
   // For BLOCKS_LANGUAGE_VERSION 23:
   // - Bitwise and, ior, and xor blocks were added.
+  // For BLOCKS_LANGUAGE_VERSION 24:
+  // - List reverse block was added.
 
-  public static final int BLOCKS_LANGUAGE_VERSION = 23;
+  public static final int BLOCKS_LANGUAGE_VERSION = 24;
 
   // ................................. Component Version Numbers ..................................
 

appinventor/docs/reference/blocks/lists.html

@@ -220,6 +220,7 @@ jQuery.extend(Drupal.settings, {"basePath":"\/","pathPrefix":"","ajaxPageState":
 <li><a href="#append">append to list</a></li>
 <li><a href="#copy">copy list</a></li>
 <li><a href="#isalist">is a list?</a></li>
+<li><a href="#reverse">reverse list</a></li>
 <li><a href="#listtocsvrow">list to csv row</a></li>
 <li><a href="#listtocsvtable">list to csv table</a></li>
 <li><a href="#listfromcsvrow">list from csv row</a></li>
@@ -274,6 +275,9 @@ the members of the sublists are not themselves members of the list. For example,
 <h3 id="isalist">is a list?</h3>
 <p><img src="images/lists/isalist.png" /></p>
 <p>If <em>thing</em> is a list, returns true; otherwise, returns false.</p>
+<h3 id="reverse">reverse list</h3>
+<p><img src="images/lists/reverse.png" /></p>
+<p>Reverses the order of input list and returns it as a new list.</p>
 <h3 id="listtocsvrow">list to csv row</h3>
 <p><img src="images/lists/listtocsvrow.png" /></p>
 <p>Interprets the list as a row of a table and returns a CSV (comma-separated value) text representing the row.<br />