feat: replace next-themes with a custom ThemeProvider

To be honest, next-themes was working fine. However since I use a theme
provider for Prism code blocks, some code is duplicated between this
app and the library. So I prefer to use a custom Provider without the
options I don't need.

1 files changed, 82 insertions, 0 deletions

diff --git a/src/utils/hooks/use-theme/use-theme.test.tsx b/src/utils/hooks/use-theme/use-theme.test.tsx
new file mode 100644
index 0000000..feaabfa
--- /dev/null
+++ b/src/utils/hooks/use-theme/use-theme.test.tsx
@@ -0,0 +1,82 @@
+import { describe, expect, it } from '@jest/globals';
+import { act, renderHook } from '@testing-library/react';
+import type { FC, ReactNode } from 'react';
+import { ThemeProvider, type ThemeProviderProps } from '../../providers';
+import { useTheme } from './use-theme';
+
+const createWrapper = (
+  Wrapper: FC<ThemeProviderProps>,
+  config: ThemeProviderProps
+) =>
+  function CreatedWrapper({ children }: { children: ReactNode }) {
+    return <Wrapper {...config}>{children}</Wrapper>;
+  };
+
+describe('useTheme', () => {
+  it('should return the default value without provider and prevent update', () => {
+    const defaultTheme = 'system';
+    const { result } = renderHook(() => useTheme());
+
+    expect(result.current.theme).toBe(defaultTheme);
+
+    act(() => result.current.setTheme('dark'));
+
+    expect(result.current.theme).toBe(defaultTheme);
+  });
+
+  it('can update the value', () => {
+    const defaultTheme = 'dark';
+
+    const { result } = renderHook(() => useTheme(), {
+      wrapper: createWrapper(ThemeProvider, {
+        attribute: 'magnam',
+        defaultTheme,
+        storageKey: 'repellat',
+      }),
+    });
+
+    expect(result.current.theme).toBe(defaultTheme);
+
+    const newTheme = 'light';
+
+    act(() => result.current.setTheme(newTheme));
+
+    expect(result.current.theme).toBe(newTheme);
+  });
+
+  it('can toggle the theme from dark to light', () => {
+    const defaultTheme = 'dark';
+
+    const { result } = renderHook(() => useTheme(), {
+      wrapper: createWrapper(ThemeProvider, {
+        attribute: 'voluptatibus',
+        defaultTheme,
+        storageKey: 'qui',
+      }),
+    });
+
+    expect(result.current.theme).toBe(defaultTheme);
+
+    act(() => result.current.toggleTheme());
+
+    expect(result.current.theme).toBe('light');
+  });
+
+  it('can toggle the theme from light to dark', () => {
+    const defaultTheme = 'light';
+
+    const { result } = renderHook(() => useTheme(), {
+      wrapper: createWrapper(ThemeProvider, {
+        attribute: 'sed',
+        defaultTheme,
+        storageKey: 'ut',
+      }),
+    });
+
+    expect(result.current.theme).toBe(defaultTheme);
+
+    act(() => result.current.toggleTheme());
+
+    expect(result.current.theme).toBe('dark');
+  });
+});