issue-171 many-to-one replacement spec

Author: dhilt

tests/adapter.replace.spec.ts

@@ -29,24 +29,69 @@ const configList: TestBedConfig[] = [{
     indexToReplace: baseSettings.maxIndex,
     token: 'last'
   }
-}].map(config => ({ ...config, datasourceClass: getDatasourceReplacementsClass(config.datasourceSettings) }));
+}].map(config => ({
+  ...config,
+  datasourceClass: getDatasourceReplacementsClass(config.datasourceSettings)
+}));
+
+const someToOneConfigList: TestBedConfig[] = [{
+  datasourceSettings: { ...baseSettings },
+  custom: {
+    indexesToReplace: [
+      baseSettings.minIndex + 1,
+      baseSettings.minIndex + 2,
+      baseSettings.minIndex + 3
+    ],
+    token: 'middle'
+  }
+}, {
+  datasourceSettings: { ...baseSettings },
+  custom: {
+    indexesToReplace: [
+      baseSettings.minIndex,
+      baseSettings.minIndex + 1,
+      baseSettings.minIndex + 2
+    ],
+    token: 'first'
+  }
+}, {
+  datasourceSettings: { ...baseSettings, startIndex: baseSettings.maxIndex },
+  custom: {
+    indexesToReplace: [
+      baseSettings.maxIndex - 2,
+      baseSettings.maxIndex - 1,
+      baseSettings.maxIndex
+    ],
+    token: 'last'
+  }
+}].map(config => ({
+  ...config,
+  datasourceClass: getDatasourceReplacementsClass(config.datasourceSettings)
+}));
+
 
 const shouldReplace = (config: TestBedConfig) => (misc: Misc) => async (done: Function) => {
   await misc.relaxNext();
   const { adapter } = misc;
-  const { custom: { indexToReplace: index, token } } = config;
+  const { custom: { indexToReplace: index, indexesToReplace: indexes, token } } = config;
   const { datasourceSettings: { minIndex, itemSize } } = config;
-  const maxScrollPosition = misc.getMaxScrollPosition();
-  const position = token === 'last' ? maxScrollPosition : (index - 1 + minIndex - 1) * itemSize;
-  const newItem = generateItem(index);
+  const diff = indexes ? indexes.length : 1;
+  const maxScrollPosition = misc.getMaxScrollPosition() - (diff - 1) * misc.getItemSize();
+  const newIndex = indexes ? indexes[0] : index;
+  const position = token === 'last' ? maxScrollPosition : (newIndex - 1 + minIndex - 1) * itemSize;
+  const newItem = generateItem(newIndex);
   newItem.text += '*';
 
-  // replace at the Datasource level
-  (misc.datasource as any).replaceOne(index, newItem);
+  // replace at the Datasource level (component)
+  if (index) {
+    (misc.datasource as any).replaceOneToOne(index, newItem);
+  } else if (indexes) {
+    (misc.datasource as any).replaceManyToOne(indexes, newItem);
+  }
 
-  // replace at the Viewport level (Adapter)
+  // replace at the Viewport level (scroller)
   await adapter.replace({
-    predicate: ({ $index }) => [index].includes($index),
+    predicate: ({ $index }) => (indexes || [index]).includes($index),
     items: [newItem]
   });
 
@@ -58,12 +103,21 @@ const shouldReplace = (config: TestBedConfig) => (misc: Misc) => async (done: Fu
     await misc.relaxNext();
   }
 
+  // check replaced item
+  if (token === 'last') {
+    expect(adapter.lastVisible.$index).toEqual(newIndex);
+  } else {
+    expect(adapter.firstVisible.$index).toEqual(newIndex);
+  }
+  expect(misc.getElementText(newIndex)).toEqual(newIndex + ': ' + newItem.text);
+
+  // check the next item
   if (token === 'last') {
-    expect(adapter.lastVisible.$index).toEqual(index);
+    expect(misc.checkElementContent(newIndex - 1, newIndex - 1)).toEqual(true);
   } else {
-    expect(adapter.firstVisible.$index).toEqual(index);
+    expect(misc.checkElementContent(newIndex + 1, newIndex + diff)).toEqual(true);
   }
-  expect(misc.getElementText(index)).toEqual(index + ': ' + newItem.text);
+
   done();
 };
 
@@ -79,4 +133,14 @@ describe('Adapter Replace Spec', () => {
     )
   );
 
+  describe('some-to-one replacement', () =>
+    someToOneConfigList.forEach(config =>
+      makeTest({
+        title: `should work (${config.custom.token})`,
+        config,
+        it: shouldReplace(config)
+      })
+    )
+  );
+
 });

tests/scaffolding/datasources/class.ts

@@ -68,10 +68,30 @@ export const getDatasourceReplacementsClass = (settings: Settings) =>
       };
     }
 
-    replaceOne(idToReplace: number, item: Item) {
+    replaceOneToOne(idToReplace: number, item: Item) {
       const itemToReplace = this.data.find(({ id }) => id === idToReplace);
       if (itemToReplace) {
         Object.assign(itemToReplace, item);
       }
     }
+
+    replaceManyToOne(idsToReplace: number[], item: Item) {
+      idsToReplace.sort((a, b) => a - b);
+      const minId = idsToReplace[0];
+      const maxId = idsToReplace.slice(1).reduce((acc, id) =>
+        // only continuous series allowed
+        id === acc + 1 ? id : acc, minId
+      );
+      const diff = maxId - minId;
+      this.data = this.data.reduce((acc, _item: Item) => {
+        if (_item.id < minId) {
+          acc.push(_item);
+        } else if (_item.id === minId) {
+          acc.push(item);
+        } else if (_item.id > maxId) {
+          acc.push({ ..._item, id: _item.id - diff });
+        }
+        return acc;
+      }, [] as Item[]);
+    }
   };