[vercel skip] chore (core) document and test Stack.home

packages/core/src/stack.mjs

@@ -52,30 +52,27 @@ Stack.prototype.home = function () {
   for (const part of this.getPartList()) {
     part.__boundary()
 
-    const transforms = part.attributes.get('transform')
+    // get all corners of the part's bounds
     let tl = part.topLeft || this.topLeft
     let br = part.bottomRight || this.bottomRight
     let tr = new Point(br.x, tl.y)
     let bl = new Point(tl.x, br.y)
 
+    // if there are transforms on the part, apply them to the corners so that we have the correct bounds
+    const transforms = part.attributes.getAsArray('transform')
     if (transforms) {
-      const combinedTransform =
-        typeof transforms === 'string' ? transforms : utils.combineTransforms(transforms)
+      const combinedTransform = utils.combineTransforms(transforms)
 
-      tl = utils.applyTransformToPoint(combinedTransform, part.topLeft.copy())
-      br = utils.applyTransformToPoint(combinedTransform, part.bottomRight.copy())
-      bl = utils.applyTransformToPoint(
-        combinedTransform,
-        new Point(part.topLeft.x, part.bottomRight.y)
-      )
-      tr = utils.applyTransformToPoint(
-        combinedTransform,
-        new Point(part.bottomRight.x, part.topLeft.y)
-      )
+      tl = utils.applyTransformToPoint(combinedTransform, tl.copy())
+      br = utils.applyTransformToPoint(combinedTransform, br.copy())
+      tr = utils.applyTransformToPoint(combinedTransform, tr.copy())
+      bl = utils.applyTransformToPoint(combinedTransform, bl.copy())
     }
 
+    // get the top left, the minimum x and y values of any corner
     this.topLeft.x = Math.min(this.topLeft.x, tl.x, br.x, bl.x, tr.x)
     this.topLeft.y = Math.min(this.topLeft.y, tl.y, br.y, bl.y, tr.y)
+    // get the bottom right, the maximum x and y values of any corner
     this.bottomRight.x = Math.max(this.bottomRight.x, tl.x, br.x, bl.x, tr.x)
     this.bottomRight.y = Math.max(this.bottomRight.y, tl.y, br.y, bl.y, tr.y)
   }

packages/core/tests/stacks.test.mjs

@@ -1,5 +1,6 @@
 import chai from 'chai'
-import { Design } from '../src/index.mjs'
+import { Design, Point, Attributes } from '../src/index.mjs'
+import { Stack } from '../src/stack.mjs'
 
 const expect = chai.expect
 
@@ -173,6 +174,52 @@ describe('Stacks', () => {
     })
   })
 
+  describe('Stack.prototype.home()', () => {
+    function dummyPart(tl, br) {
+      return {
+        __boundary: () => null,
+        topLeft: new Point(tl.x, tl.y),
+        bottomRight: new Point(br.x, br.y),
+        attributes: new Attributes(),
+      }
+    }
+
+    it('Should calculate the bounds using all part bounds', () => {
+      const stack = new Stack('test')
+      stack.context = { settings: [{ margin: 0 }] }
+      const expectedTlX = -1
+      const expectedTlY = -2
+      const expectedBrX = 20
+      const expectedBrY = 20
+
+      stack.addPart(dummyPart({ x: 0, y: expectedTlY }, { x: expectedBrX, y: 10 }))
+
+      stack.addPart(dummyPart({ x: expectedTlX, y: 0 }, { x: expectedBrX, y: expectedBrY }))
+
+      stack.home()
+      expect(stack.topLeft.x).to.equal(expectedTlX)
+      expect(stack.topLeft.y).to.equal(expectedTlY)
+      expect(stack.bottomRight.x).to.equal(expectedBrX)
+      expect(stack.bottomRight.y).to.equal(expectedBrY)
+    })
+
+    it('Should calculate the bounds using all transformed part bounds', () => {
+      const stack = new Stack('test')
+      stack.context = { settings: [{ margin: 0 }] }
+
+      const part1 = dummyPart({ x: 0, y: 0 }, { x: 10, y: 10 })
+      part1.attributes.add('transform', 'scale(1, -1)')
+      part1.attributes.add('transform', 'rotate(45)')
+      stack.addPart(part1)
+
+      stack.home()
+      expect(stack.topLeft.x).to.equal(-7.071067811865475)
+      expect(stack.topLeft.y).to.equal(-14.142135623730951)
+      expect(stack.bottomRight.x).to.equal(7.0710678118654755)
+      expect(stack.bottomRight.y).to.equal(0)
+    })
+  })
+
   it('Should get the anchor for the stack', () => {
     const part = {
       name: 'test',