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461import { describe, it, expect } from "vitest";
import vinext from "../packages/vinext/src/index.js";
import localFont, { getSSRFontStyles } from "../packages/vinext/src/shims/font-local.js";
import type { Plugin } from "vite";
// โโ Helpers โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ
/** Unwrap a Vite plugin hook that may use the object-with-filter format */
function unwrapHook(hook: any): Function {
return typeof hook === "function" ? hook : hook?.handler;
}
/** Extract the vinext:local-fonts plugin from the plugin array */
function getLocalFontsPlugin(): Plugin {
const plugins = vinext() as Plugin[];
const plugin = plugins.find((p) => p.name === "vinext:local-fonts");
if (!plugin) throw new Error("vinext:local-fonts plugin not found");
return plugin;
}
// โโ Plugin existence โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ
describe("vinext:local-fonts plugin", () => {
it("exists in the plugin array", () => {
const plugin = getLocalFontsPlugin();
expect(plugin.name).toBe("vinext:local-fonts");
expect(plugin.enforce).toBe("pre");
});
// โโ Guard clauses โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ
it("returns null for files without next/font/local", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = `import React from 'react';\nconst x = 1;`;
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).toBeNull();
});
it("returns null for node_modules files", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = `import localFont from 'next/font/local';\nconst f = localFont({ src: './font.woff2' });`;
const result = transform.call(plugin, code, "node_modules/some-pkg/index.ts");
expect(result).toBeNull();
});
it("returns null for virtual modules", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = `import localFont from 'next/font/local';\nconst f = localFont({ src: './font.woff2' });`;
const result = transform.call(plugin, code, "\0virtual:something");
expect(result).toBeNull();
});
it("returns null for non-script files", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = `import localFont from 'next/font/local';\nconst f = localFont({ src: './font.woff2' });`;
const result = transform.call(plugin, code, "/app/styles.css");
expect(result).toBeNull();
});
it("returns null when code mentions next/font/local but has no import", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = `// This file mentions next/font/local in a comment\nconst x = 1;`;
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).toBeNull();
});
it("returns null when import exists but no font file paths", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = `import localFont from 'next/font/local';\n// no call with font paths`;
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).toBeNull();
});
// โโ Simple string src โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ
it("transforms a simple string src path", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const myFont = localFont({ src: "./my-font.woff2" });`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
// Should add an import for the font file
expect(result.code).toContain(`import __vinext_local_font_0 from "./my-font.woff2";`);
// Should replace the path string with the import variable
expect(result.code).toContain("src: __vinext_local_font_0");
// Should NOT contain the original quoted path in the src property
expect(result.code).not.toMatch(/src:\s*["']\.\/my-font\.woff2["']/);
expect(result.map).toBeDefined();
});
// โโ Object src with path property โโโโโโโโโโโโโโโโโโโโโโโโโโโโ
it("transforms a single source object with path property", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const myFont = localFont({ src: { path: "./font.woff2", weight: "400" } });`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
expect(result.code).toContain(`import __vinext_local_font_0 from "./font.woff2";`);
expect(result.code).toContain("path: __vinext_local_font_0");
expect(result.code).not.toMatch(/path:\s*["']\.\/font\.woff2["']/);
});
// โโ Array of source objects โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ
it("transforms multiple font sources in an array", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const inter = localFont({`,
` src: [`,
` { path: "./fonts/InterVariable.woff2", weight: "100 900", style: "normal" },`,
` { path: "./fonts/InterVariable-Italic.woff2", weight: "100 900", style: "italic" },`,
` ],`,
` variable: "--font-inter",`,
`});`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
// Two imports should be added
expect(result.code).toContain(`import __vinext_local_font_0 from "./fonts/InterVariable.woff2";`);
expect(result.code).toContain(`import __vinext_local_font_1 from "./fonts/InterVariable-Italic.woff2";`);
// Both paths should be replaced
expect(result.code).toContain("path: __vinext_local_font_0");
expect(result.code).toContain("path: __vinext_local_font_1");
// Original paths should be gone
expect(result.code).not.toMatch(/path:\s*["']\.\/fonts\/InterVariable\.woff2["']/);
expect(result.code).not.toMatch(/path:\s*["']\.\/fonts\/InterVariable-Italic\.woff2["']/);
});
// โโ Font file extensions โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ
it("handles .woff files", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const f = localFont({ src: "./font.woff" });`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
expect(result.code).toContain(`import __vinext_local_font_0 from "./font.woff";`);
});
it("handles .ttf files", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const f = localFont({ src: "./font.ttf" });`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
expect(result.code).toContain(`import __vinext_local_font_0 from "./font.ttf";`);
});
it("handles .otf files", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const f = localFont({ src: "./font.otf" });`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
expect(result.code).toContain(`import __vinext_local_font_0 from "./font.otf";`);
});
it("handles .eot files", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const f = localFont({ src: "./font.eot" });`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
expect(result.code).toContain(`import __vinext_local_font_0 from "./font.eot";`);
});
// โโ Quote styles โ๏ฟฝ๏ฟฝโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ
it("handles single-quoted paths", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const f = localFont({ src: './font.woff2' });`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
expect(result.code).toContain(`import __vinext_local_font_0 from "./font.woff2";`);
expect(result.code).toContain("src: __vinext_local_font_0");
});
it("handles double-quoted paths", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const f = localFont({ src: "./font.woff2" });`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
expect(result.code).toContain("src: __vinext_local_font_0");
});
// โโ Preserves other code โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ
it("preserves non-font code alongside transforms", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import React from 'react';`,
`import localFont from 'next/font/local';`,
`import { useState } from 'react';`,
``,
`const myFont = localFont({ src: "./font.woff2" });`,
``,
`export default function Layout() { return null; }`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
// Non-font imports should be preserved
expect(result.code).toContain(`import React from 'react'`);
expect(result.code).toContain(`import { useState } from 'react'`);
expect(result.code).toContain(`import localFont from 'next/font/local'`);
// Font path should be transformed
expect(result.code).toContain("src: __vinext_local_font_0");
// Export should be preserved
expect(result.code).toContain("export default function Layout");
});
it("preserves variable and display options", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const f = localFont({`,
` src: "./font.woff2",`,
` variable: "--font-custom",`,
` display: "swap",`,
`});`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
expect(result.code).toContain('variable: "--font-custom"');
expect(result.code).toContain('display: "swap"');
});
// โโ Path styles โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ
it("handles relative paths with subdirectories", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const f = localFont({ src: "./assets/fonts/my-font.woff2" });`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
expect(result.code).toContain(`import __vinext_local_font_0 from "./assets/fonts/my-font.woff2";`);
});
it("handles parent-relative paths", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const f = localFont({ src: "../fonts/my-font.woff2" });`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
expect(result.code).toContain(`import __vinext_local_font_0 from "../fonts/my-font.woff2";`);
});
// โโ Security: CSS injection via font file paths โโโโโโโโโโโโ
it("escapes single quotes in font file paths to prevent CSS injection", () => {
const beforeCount = getSSRFontStyles().length;
// A crafted font path with a single quote could break out of url('...')
const result = localFont({
src: "./font'); } body { color: red; } .x { src: url('.woff2",
});
// The font should still load (it's escaped, not rejected)
expect(result.className).toBeDefined();
expect(result.style.fontFamily).toBeDefined();
// Check that the generated CSS has the quote escaped
const styles = getSSRFontStyles();
const newStyles = styles.slice(beforeCount);
const fontFaceCSS = newStyles.find((s: string) => s.includes("@font-face"));
if (fontFaceCSS) {
// Should contain escaped quote, not raw breakout
expect(fontFaceCSS).not.toContain("url('./font');");
expect(fontFaceCSS).toContain("\\'");
}
});
it("escapes backslashes in font file paths", () => {
const result = localFont({
src: "./fonts\\evil.woff2",
});
expect(result.className).toBeDefined();
expect(result.style.fontFamily).toBeDefined();
});
it("sanitizes fallback font names with CSS injection attempts", () => {
const result = localFont({
src: "./font.woff2",
fallback: ["sans-serif", "'); } body { color: red; } .x { font-family: ('"],
});
expect(result.className).toBeDefined();
// The malicious single quotes in the fallback should be escaped with \'
// so they can't break out of the CSS string context
expect(result.style.fontFamily).toContain("\\'");
// Should still have sans-serif as a safe generic
expect(result.style.fontFamily).toContain("sans-serif");
// The malicious fallback should be wrapped in quotes (not used as a bare identifier)
// so it's treated as a CSS string value. The sanitizeFallback function
// wraps non-generic names in quotes and escapes internal quotes.
expect(result.style.fontFamily).toMatch(/'\\'.*\\'/);
});
it("rejects invalid CSS variable names", () => {
const beforeCount = getSSRFontStyles().length;
const result = localFont({
src: "./font.woff2",
variable: "--x; } body { color: red; } .y { --z",
});
expect(result.className).toBeDefined();
// The malicious variable should be rejected โ no variable class should be injected
const styles = getSSRFontStyles();
const newStyles = styles.slice(beforeCount);
// Should NOT contain the injection payload in any generated CSS
for (const css of newStyles) {
expect(css).not.toContain("color: red");
expect(css).not.toContain("color:red");
}
});
it("accepts valid CSS variable names", () => {
const result = localFont({
src: "./font.woff2",
variable: "--font-custom",
});
expect(result.className).toBeDefined();
// variable returns a class name, not the variable name
expect(result.variable).toMatch(/^__variable_local_\d+$/);
});
it("sanitizes declaration props to prevent injection", () => {
const beforeCount = getSSRFontStyles().length;
const result = localFont({
src: "./font.woff2",
declarations: [
{ prop: "font-weight", value: "400" }, // valid
{ prop: "} body { color: red; } .x { font-weight", value: "400" }, // malicious prop
],
});
expect(result.className).toBeDefined();
const styles = getSSRFontStyles();
const newStyles = styles.slice(beforeCount);
// Valid declaration should be present
const hasFontWeight = newStyles.some((s: string) => s.includes("font-weight: 400"));
expect(hasFontWeight).toBe(true);
// Malicious declaration should be rejected entirely
for (const css of newStyles) {
expect(css).not.toContain("color: red");
expect(css).not.toContain("color:red");
}
});
it("sanitizes declaration values to prevent injection", () => {
const beforeCount = getSSRFontStyles().length;
const result = localFont({
src: "./font.woff2",
declarations: [
{ prop: "font-weight", value: "400; } body { color: red; } .x { font-weight: 400" },
],
});
expect(result.className).toBeDefined();
const styles = getSSRFontStyles();
const newStyles = styles.slice(beforeCount);
// The value with } should be rejected โ no rule should contain the injection
for (const css of newStyles) {
expect(css).not.toContain("color: red");
expect(css).not.toContain("color:red");
}
});
// โโ Sourcemap โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ
it("generates a sourcemap", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from 'next/font/local';`,
`const f = localFont({ src: "./font.woff2" });`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
expect(result.map).toBeDefined();
expect(result.map.mappings).toBeDefined();
});
// โโ Realistic layout example โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ
it("transforms a realistic Next.js layout file", () => {
const plugin = getLocalFontsPlugin();
const transform = unwrapHook(plugin.transform);
const code = [
`import localFont from "next/font/local";`,
``,
`const inter = localFont({`,
` src: [`,
` { path: "./fonts/InterVariable.woff2", weight: "100 900", style: "normal" },`,
` { path: "./fonts/InterVariable-Italic.woff2", weight: "100 900", style: "italic" },`,
` ],`,
` variable: "--font-inter",`,
` display: "swap",`,
`});`,
``,
`export default function RootLayout({ children }: { children: React.ReactNode }) {`,
` return (`,
` <html lang="en" className={inter.variable}>`,
` <body>{children}</body>`,
` </html>`,
` );`,
`}`,
].join("\n");
const result = transform.call(plugin, code, "/app/layout.tsx");
expect(result).not.toBeNull();
// Should add two font imports
expect(result.code).toContain(`import __vinext_local_font_0 from "./fonts/InterVariable.woff2";`);
expect(result.code).toContain(`import __vinext_local_font_1 from "./fonts/InterVariable-Italic.woff2";`);
// Paths should be replaced
expect(result.code).toContain("path: __vinext_local_font_0");
expect(result.code).toContain("path: __vinext_local_font_1");
// Other options and JSX should be preserved
expect(result.code).toContain('variable: "--font-inter"');
expect(result.code).toContain('display: "swap"');
expect(result.code).toContain("className={inter.variable}");
expect(result.code).toContain("export default function RootLayout");
});
});