test: increase coverage

Signed-off-by: Andres Correa Casablanca <castarco@coderspirit.xyz>

Author: castarco

src/layouts.ts

@@ -119,11 +119,9 @@ const _inPlaceEvenSpacingUpdate = (
 ): void => {
 	if (numChildren === 0) {
 		tree.meta.pos.x += shift
-		tree.meta.m = 0
 	} else if (numChildren === 1) {
 		// eslint-disable-next-line @typescript-eslint/no-non-null-assertion
 		tree.meta.pos.x = tree.children![0]!.node.meta.pos.x
-		tree.meta.m = 0
 	} else {
 		const c = // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
 			(tree.children![0]!.node.meta.pos.x +
@@ -132,6 +130,7 @@ const _inPlaceEvenSpacingUpdate = (
 			0.5
 		tree.meta.pos.x = Math.max(offsets[depth] ?? 0, c)
 	}
+	delete tree.meta.m
 	tracer.maxX = Math.max(tracer.maxX, tree.meta.pos.x)
 	offsets[depth] = 1 + tree.meta.pos.x
 }

src/tests/layouts.test.ts

@@ -1,5 +1,5 @@
+import { computeCenter3Layout, computeLeftShiftLayout } from '../layouts'
 import { describe, expect, it } from 'vitest'
-import { computeLeftShiftLayout } from '../layouts'
 
 describe('computeLeftShiftLayout', () => {
 	it('sets x=0,y=0 for a single-node tree, and data is preserved', () => {
@@ -349,3 +349,79 @@ describe('computeLeftShiftLayout', () => {
 		})
 	})
 })
+
+describe('computeCenter3Layout', () => {
+	it('sets x=0,y=0 for a single-node tree, and data is preserved', () => {
+		const resultWithoutChildren = computeCenter3Layout({
+			data: { v: 42 },
+		})
+		expect(resultWithoutChildren).toEqual({
+			maxX: 0,
+			maxY: 0,
+			tree: {
+				data: { v: 42 },
+				meta: {
+					isRoot: true,
+					isLeaf: true,
+					pos: { x: 0, y: 0 },
+				},
+			},
+		})
+
+		const resultWithEmptyChildren = computeCenter3Layout({
+			data: { v: 42 },
+			children: [],
+		})
+		expect(resultWithEmptyChildren).toEqual({
+			maxX: 0,
+			maxY: 0,
+			tree: {
+				data: { v: 42 },
+				children: [],
+				meta: {
+					isRoot: true,
+					isLeaf: true,
+					pos: { x: 0, y: 0 },
+				},
+			},
+		})
+	})
+
+	it('sets x=0,y=0 & x=0,y=1 for tree with single child', () => {
+		const result = computeCenter3Layout({
+			data: { v: 42 },
+			children: [
+				{
+					edgeData: {},
+					node: { data: { v: 43 } },
+				},
+			],
+		})
+
+		expect(result).toEqual({
+			maxX: 0,
+			maxY: 1,
+			tree: {
+				data: { v: 42 },
+				children: [
+					{
+						edgeData: {},
+						node: {
+							data: { v: 43 },
+							meta: {
+								isRoot: false,
+								isLeaf: true,
+								pos: { x: 0, y: 1 },
+							},
+						},
+					},
+				],
+				meta: {
+					isRoot: true,
+					isLeaf: false,
+					pos: { x: 0, y: 0 },
+				},
+			},
+		})
+	})
+})