grid: getNeighborViews

src/vs/base/browser/ui/grid/grid.ts

@@ -42,7 +42,7 @@ function getNode<T extends IView>(node: GridNode<T>, location: number[]): GridNo
 	return getNode(node.children[index], rest);
 }
 
-function getViews<T extends IView>(node: GridNode<T>): T[] {
+function getAllViews<T extends IView>(node: GridNode<T>): T[] {
 	const result: T[] = [];
 
 	function collectViews(node: GridNode<T>): void {
@@ -246,61 +246,57 @@ export class Grid<T extends IView> implements IDisposable {
 
 	getNeighborViews(view: T, direction: Direction, wrap: boolean = false): T[] {
 		const location = this.getViewLocation(view);
-		const locationOrientation = getLocationOrientation(this.orientation, location);
-		const directionOrientation = getDirectionOrientation(direction);
-		const diff = direction === Direction.Up || direction === Direction.Left ? -1 : 1;
-		const root = this.getViews();
-		const [parentLocation, index] = tail2(location);
-
-		if (locationOrientation === directionOrientation) {
-			const parent = getNode(root, parentLocation);
-
-			if (!isGridBranchNode(parent)) {
-				throw new Error('Invalid location');
-			}
+		const result = this._getNeighborViews(location, direction);
 
-			let neighborIndex = index + diff;
-
-			if (!wrap && (neighborIndex === -1 || neighborIndex >= parent.children.length)) {
-				return [];
-			}
+		if (result.length > 0 || !wrap) {
+			return result;
+		}
 
-			neighborIndex = neighborIndex % parent.children.length;
-			const neighbor = parent.children[neighborIndex];
+		const directionOrientation = getDirectionOrientation(direction);
+		const ancestorLocation = location.slice(0, directionOrientation === this.orientation ? 0 : 1);
+		const root = this.getViews();
+		const ancestorParent = getNode(root, ancestorLocation);
 
-			return getViews(neighbor);
+		if (!isGridBranchNode(ancestorParent)) {
+			return [ancestorParent.view];
+		}
 
+		if (direction === Direction.Up || direction === Direction.Left) {
+			return getAllViews(ancestorParent.children[ancestorParent.children.length - 1]);
 		} else {
-			if (parentLocation.length === 0) {
-				return [];
-			}
-
-			const [grandParentLocation, parentIndex] = tail2(parentLocation);
-			const grandParent = getNode(root, grandParentLocation);
+			return getAllViews(ancestorParent.children[0]);
+		}
+	}
 
-			if (!isGridBranchNode(grandParent)) {
-				throw new Error('Invalid location');
-			}
+	_getNeighborViews(location: number[], direction: Direction): T[] {
+		if (location.length === 0) {
+			return [];
+		}
 
-			let uncleIndex = parentIndex + diff;
+		const locationOrientation = getLocationOrientation(this.orientation, location);
+		const directionOrientation = getDirectionOrientation(direction);
+		const [parentLocation, index] = tail2(location);
 
-			if (!wrap && (uncleIndex === -1 || uncleIndex >= grandParent.children.length)) {
-				return [];
-			}
+		if (locationOrientation !== directionOrientation) {
+			return this._getNeighborViews(parentLocation, direction);
+		}
 
-			uncleIndex = uncleIndex % grandParent.children.length;
+		const root = this.getViews();
+		const parent = getNode(root, parentLocation);
 
-			const uncle = grandParent.children[uncleIndex];
+		if (!isGridBranchNode(parent)) {
+			throw new Error('Invalid location');
+		}
 
-			if (!isGridBranchNode(uncle)) {
-				return [uncle.view];
-			}
+		const diff = direction === Direction.Up || direction === Direction.Left ? -1 : 1;
+		let neighborIndex = index + diff;
 
-			const uncleLocation = [...grandParentLocation, uncleIndex];
-			const range = this.gridview.getViewRange(location);
-			const cousinIndexes = this.gridview.getChildrenInRange(uncleLocation, range);
-			return cousinIndexes.reduce((r, i) => [...r, ...getViews(uncle.children[i])], [] as T[]);
+		if (neighborIndex === -1 || neighborIndex >= parent.children.length) {
+			return this._getNeighborViews(parentLocation, direction);
 		}
+
+		const neighbor = parent.children[neighborIndex];
+		return getAllViews(neighbor);
 	}
 
 	private getViewLocation(view: T): number[] {

src/vs/base/test/browser/ui/grid/grid.test.ts

@@ -288,6 +288,103 @@ suite('Grid', function () {
 		assert.deepEqual(view2.size, [800, 200]);
 		assert.deepEqual(view4.size, [800, 200]);
 	});
+
+	test('getNeighborViews should work on single view layout', function () {
+		const view1 = new TestView(50, Number.MAX_VALUE, 50, Number.MAX_VALUE);
+		const grid = new Grid(container, view1);
+		grid.layout(800, 600);
+
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Up), []);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Right), []);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Down), []);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Left), []);
+
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Up, true), [view1]);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Right, true), [view1]);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Down, true), [view1]);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Left, true), [view1]);
+	});
+
+	test('getNeighborViews should work on simple layout', function () {
+		const view1 = new TestView(50, Number.MAX_VALUE, 50, Number.MAX_VALUE);
+		const grid = new Grid(container, view1);
+		grid.layout(800, 600);
+
+		const view2 = new TestView(50, Number.MAX_VALUE, 50, Number.MAX_VALUE);
+		grid.addView(view2, Sizing.Distribute, view1, Direction.Down);
+
+		const view3 = new TestView(50, Number.MAX_VALUE, 50, Number.MAX_VALUE);
+		grid.addView(view3, Sizing.Distribute, view2, Direction.Down);
+
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Up), []);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Right), []);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Down), [view2]);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Left), []);
+
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Up, true), [view3]);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Right, true), [view1]);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Down, true), [view2]);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Left, true), [view1]);
+
+		assert.deepEqual(grid.getNeighborViews(view2, Direction.Up), [view1]);
+		assert.deepEqual(grid.getNeighborViews(view2, Direction.Right), []);
+		assert.deepEqual(grid.getNeighborViews(view2, Direction.Down), [view3]);
+		assert.deepEqual(grid.getNeighborViews(view2, Direction.Left), []);
+
+		assert.deepEqual(grid.getNeighborViews(view2, Direction.Up, true), [view1]);
+		assert.deepEqual(grid.getNeighborViews(view2, Direction.Right, true), [view2]);
+		assert.deepEqual(grid.getNeighborViews(view2, Direction.Down, true), [view3]);
+		assert.deepEqual(grid.getNeighborViews(view2, Direction.Left, true), [view2]);
+
+		assert.deepEqual(grid.getNeighborViews(view3, Direction.Up), [view2]);
+		assert.deepEqual(grid.getNeighborViews(view3, Direction.Right), []);
+		assert.deepEqual(grid.getNeighborViews(view3, Direction.Down), []);
+		assert.deepEqual(grid.getNeighborViews(view3, Direction.Left), []);
+
+		assert.deepEqual(grid.getNeighborViews(view3, Direction.Up, true), [view2]);
+		assert.deepEqual(grid.getNeighborViews(view3, Direction.Right, true), [view3]);
+		assert.deepEqual(grid.getNeighborViews(view3, Direction.Down, true), [view1]);
+		assert.deepEqual(grid.getNeighborViews(view3, Direction.Left, true), [view3]);
+	});
+
+	test('getNeighborViews should work on a complex layout', function () {
+		const view1 = new TestView(50, Number.MAX_VALUE, 50, Number.MAX_VALUE);
+		const grid = new Grid(container, view1);
+		grid.layout(800, 600);
+
+		const view2 = new TestView(50, Number.MAX_VALUE, 50, Number.MAX_VALUE);
+		grid.addView(view2, Sizing.Distribute, view1, Direction.Down);
+
+		const view3 = new TestView(50, Number.MAX_VALUE, 50, Number.MAX_VALUE);
+		grid.addView(view3, Sizing.Distribute, view2, Direction.Down);
+
+		const view4 = new TestView(50, Number.MAX_VALUE, 50, Number.MAX_VALUE);
+		grid.addView(view4, Sizing.Distribute, view2, Direction.Right);
+
+		const view5 = new TestView(50, Number.MAX_VALUE, 50, Number.MAX_VALUE);
+		grid.addView(view5, Sizing.Distribute, view4, Direction.Down);
+
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Up), []);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Right), []);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Down), [view2, view4, view5]);
+		assert.deepEqual(grid.getNeighborViews(view1, Direction.Left), []);
+		assert.deepEqual(grid.getNeighborViews(view2, Direction.Up), [view1]);
+		assert.deepEqual(grid.getNeighborViews(view2, Direction.Right), [view4, view5]);
+		assert.deepEqual(grid.getNeighborViews(view2, Direction.Down), [view3]);
+		assert.deepEqual(grid.getNeighborViews(view2, Direction.Left), []);
+		assert.deepEqual(grid.getNeighborViews(view4, Direction.Up), [view1]);
+		assert.deepEqual(grid.getNeighborViews(view4, Direction.Right), []);
+		assert.deepEqual(grid.getNeighborViews(view4, Direction.Down), [view5]);
+		assert.deepEqual(grid.getNeighborViews(view4, Direction.Left), [view2]);
+		assert.deepEqual(grid.getNeighborViews(view5, Direction.Up), [view4]);
+		assert.deepEqual(grid.getNeighborViews(view5, Direction.Right), []);
+		assert.deepEqual(grid.getNeighborViews(view5, Direction.Down), [view3]);
+		assert.deepEqual(grid.getNeighborViews(view5, Direction.Left), [view2]);
+		assert.deepEqual(grid.getNeighborViews(view3, Direction.Up), [view2, view4, view5]);
+		assert.deepEqual(grid.getNeighborViews(view3, Direction.Right), []);
+		assert.deepEqual(grid.getNeighborViews(view3, Direction.Down), []);
+		assert.deepEqual(grid.getNeighborViews(view3, Direction.Left), []);
+	});
 });
 
 class TestSerializableView extends TestView implements ISerializableView {