Add tests for drawFoldlines

src/utils/drawing.test.js

@@ -0,0 +1,88 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+import { expect, describe, it } from 'vitest';
+
+import { drawFoldlines } from './drawing.js';
+
+describe('tests foldline drawing', () => {
+  const mockPaper = [50, 100];
+  const folioFoldsRotate = [
+    { start: { x: 0, y: 50 }, end: { x: 50, y: 50 }, dashArray: [10, 5], opacity: 0.4 },
+  ];
+  const quartoFoldsRotate = [
+    { start: { x: 25, y: 50 }, end: { x: 25, y: 0 }, dashArray: [5, 5], opacity: 0.4 },
+  ];
+  const octavoFoldsRotate = [
+    { start: { x: 25, y: 75 }, end: { x: 0, y: 75 }, dashArray: [3, 5], opacity: 0.4 },
+    ...quartoFoldsRotate,
+  ];
+  const sextidecimoFoldsRotate = [
+    { start: { x: 37.5, y: 50 }, end: { x: 37.5, y: 75 }, dashArray: [1, 5], opacity: 0.4 },
+    ...octavoFoldsRotate,
+  ];
+
+  const folioFolds = folioFoldsRotate;
+  const quartoFolds = [
+    { start: { x: 25, y: 50 }, end: { x: 25, y: 100 }, dashArray: [5, 5], opacity: 0.4 },
+  ];
+  const octavoFolds = [
+    { start: { x: 25, y: 25 }, end: { x: 100, y: 25 }, dashArray: [3, 5], opacity: 0.4 },
+    ...quartoFolds,
+  ];
+  const sextidecimoFolds = [
+    { start: { x: 12.5, y: 50 }, end: { x: 12.5, y: 25 }, dashArray: [1, 5], opacity: 0.4 },
+    ...octavoFolds,
+  ];
+
+  const results = {
+    4: {
+      frontRotate: folioFoldsRotate,
+      backRotate: [],
+      front: folioFolds,
+      back: [],
+    },
+    8: {
+      frontRotate: folioFoldsRotate,
+      backRotate: quartoFoldsRotate,
+      front: folioFolds,
+      back: quartoFolds,
+    },
+    16: {
+      frontRotate: folioFoldsRotate,
+      backRotate: octavoFoldsRotate,
+      front: folioFolds,
+      back: octavoFolds,
+    },
+    32: {
+      frontRotate: folioFoldsRotate,
+      backRotate: sextidecimoFoldsRotate,
+      front: folioFolds,
+      back: sextidecimoFolds,
+    },
+  };
+  Object.keys(results).forEach((key) => {
+    const { frontRotate, backRotate, front, back } = results[key];
+    const intKey = parseInt(key, 10);
+    it(`produces the correct foldlines for ${key}-per-sheet fronts`, () => {
+      let actual = drawFoldlines(false, false, mockPaper, intKey);
+      expect(actual).toEqual(front);
+    });
+
+    it(`produces the correct foldlines for ${key}-per-sheet backs`, () => {
+      let actual = drawFoldlines(true, false, mockPaper, intKey);
+      expect(actual).toEqual(back);
+    });
+
+    it(`produces the correct foldlines for ${key}-per-sheet fronts with duplex rotation`, () => {
+      let actual = drawFoldlines(false, true, mockPaper, intKey);
+      expect(actual).toEqual(frontRotate);
+    });
+
+    it(`produces the correct foldlines for ${key}-per-sheet backs with duplex rotation`, () => {
+      const actual = drawFoldlines(true, true, mockPaper, intKey);
+      expect(actual).toEqual(backRotate);
+    });
+  });
+});