test(svg): add constants integrity and theme safety tests

Author: amna-sehgal

lib/svg/constants.theme-contrast.test.ts

@@ -0,0 +1,46 @@
+import {
+  SVG_WIDTH,
+  SVG_HEIGHT,
+  GHOST_HEIGHT_PX,
+  LOG_SCALE_MULTIPLIER,
+  LINEAR_SCALE_MULTIPLIER,
+  MAX_LOG_HEIGHT,
+  MAX_LINEAR_HEIGHT,
+  FONT_MAP,
+  CONTRIBUTION_MILESTONES,
+  STREAK_MILESTONES,
+} from './constants';
+
+import { describe, it, expect } from 'vitest';
+
+describe('SVG constants integrity', () => {
+  it('should have valid SVG dimensions', () => {
+    expect(SVG_WIDTH).toBe(600);
+    expect(SVG_HEIGHT).toBe(420);
+  });
+  it('should keep ghost height within safe rendering range', () => {
+    expect(GHOST_HEIGHT_PX).toBeGreaterThan(0);
+    expect(GHOST_HEIGHT_PX).toBeLessThan(10);
+  });
+  it('should ensure log scale multiplier is larger than linear scale multiplier', () => {
+    expect(LOG_SCALE_MULTIPLIER).toBeGreaterThan(LINEAR_SCALE_MULTIPLIER);
+    expect(LINEAR_SCALE_MULTIPLIER).toBeGreaterThan(0);
+  });
+  it('should contain valid font mappings', () => {
+    expect(FONT_MAP.jetbrains).toContain('monospace');
+    expect(FONT_MAP.fira).toContain('monospace');
+    expect(FONT_MAP.roboto).toContain('sans-serif');
+
+    expect(Object.keys(FONT_MAP).length).toBeGreaterThan(0);
+  });
+  it('should have correctly ordered contribution milestones', () => {
+    expect(CONTRIBUTION_MILESTONES).toEqual([...CONTRIBUTION_MILESTONES].sort((a, b) => a - b));
+
+    expect(CONTRIBUTION_MILESTONES[0]).toBe(1);
+  });
+  it('should have valid streak milestones in ascending order', () => {
+    expect(STREAK_MILESTONES).toEqual([...STREAK_MILESTONES].sort((a, b) => a - b));
+
+    expect(STREAK_MILESTONES[0]).toBe(3);
+  });
+});