MOBILE-4234 mod_data: Correctly handle 0 in number fields

src/addons/mod/data/fields/number/services/handler.ts

@@ -45,17 +45,17 @@ export class AddonModDataFieldNumberHandlerService extends AddonModDataFieldText
         originalFieldData: AddonModDataEntryField,
     ): boolean {
         const fieldName = 'f_' + field.id;
-        const input = inputData[fieldName] || '';
-        const content = originalFieldData?.content || '';
+        const input = inputData[fieldName] ?? '';
+        const content = originalFieldData?.content ?? '';
 
-        return input != content;
+        return input !== content;
     }
 
     /**
      * @inheritdoc
      */
     getFieldsNotifications(field: AddonModDataField, inputData: AddonModDataSubfieldData[]): string | undefined {
-        if (field.required && (!inputData || !inputData.length || inputData[0].value == '')) {
+        if (field.required && (!inputData || !inputData.length || inputData[0].value === '')) {
             return Translate.instant('addon.mod_data.errormustsupplyvalue');
         }
     }

src/addons/mod/data/fields/text/services/handler.ts

@@ -70,7 +70,7 @@ export class AddonModDataFieldTextHandlerService implements AddonModDataFieldHan
 
         return [{
             fieldid: field.id,
-            value: inputData[fieldName] || '',
+            value: inputData[fieldName] ?? '',
         }];
     }
 
@@ -83,10 +83,10 @@ export class AddonModDataFieldTextHandlerService implements AddonModDataFieldHan
         originalFieldData: AddonModDataEntryField,
     ): boolean {
         const fieldName = 'f_' + field.id;
-        const input = inputData[fieldName] || '';
-        const content = originalFieldData?.content || '';
+        const input = inputData[fieldName] ?? '';
+        const content = originalFieldData?.content ?? '';
 
-        return input != content;
+        return input !== content;
     }
 
     /**
@@ -102,7 +102,7 @@ export class AddonModDataFieldTextHandlerService implements AddonModDataFieldHan
      * @inheritdoc
      */
     overrideData(originalContent: AddonModDataEntryField, offlineContent: CoreFormFields<string>): AddonModDataEntryField {
-        originalContent.content = offlineContent[''] || '';
+        originalContent.content = offlineContent[''] ?? '';
 
         return originalContent;
     }

src/addons/mod/data/pages/edit/edit.ts

@@ -42,6 +42,7 @@ import {
 import { AddonModDataHelper } from '../../services/data-helper';
 import { CoreDom } from '@singletons/dom';
 import { AddonModDataEntryFieldInitialized } from '../../classes/base-field-plugin-component';
+import { CoreTextUtils } from '@services/utils/text';
 
 /**
  * Page that displays the view edit page.
@@ -368,9 +369,18 @@ export class AddonModDataEditPage implements OnInit {
                             }
                         });
                     }
+
                     this.jsData!.errors = this.errors;
 
                     this.scrollToFirstError();
+
+                    if (updateEntryResult.generalnotifications?.length) {
+                        CoreDomUtils.showAlertWithOptions({
+                            header: Translate.instant('core.notice'),
+                            message: CoreTextUtils.buildMessage(updateEntryResult.generalnotifications),
+                            buttons: [Translate.instant('core.ok')],
+                        });
+                    }
                 }
             } finally {
                 modal.dismiss();

src/addons/mod/data/services/data-helper.ts

@@ -590,8 +590,8 @@ export class AddonModDataHelperProvider {
                 // WS wants values in JSON format.
                 entryFieldDataToSend.push({
                     fieldid: fieldSubdata.fieldid,
-                    subfield: fieldSubdata.subfield || '',
-                    value: value ? JSON.stringify(value) : '',
+                    subfield: fieldSubdata.subfield ?? '',
+                    value: (value || value === 0) ? JSON.stringify(value) : '',
                 });
 
                 return;

src/addons/mod/data/tests/behat/entries.feature

@@ -206,3 +206,22 @@ Feature: Users can manage entries in database activities
     Then I should find "Are you sure you want to delete this entry?" in the app
     And I press "Delete" in the app
     And I should not find "Moodle Cloud" in the app
+
+  Scenario: Handle number 0 correctly when creating entries
+    Given the following "activities" exist:
+      | activity | name      | intro     | course | idnumber |
+      | data     | Number DB | Number DB | C1     | data2    |
+    And the following "mod_data > fields" exist:
+      | database | type   | name   | description  |
+      | data2    | number | Number | Number value |
+    And I entered the data activity "Number DB" on course "Course 1" as "student1" in the app
+    When I press "Add entries" in the app
+    And I press "Save" near "Number DB" in the app
+    Then I should find "You did not fill out any fields!" in the app
+
+    When I press "OK" in the app
+    And I set the following fields to these values in the app:
+      | Number | 0 |
+    And I press "Save" near "Number DB" in the app
+    Then I should find "0" near "Number:" in the app
+    But I should not find "Save" in the app