@inlang/paraglide-js/dist/compiler/runtime/get-locale.test.js

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import { newProject } from "@inlang/sdk";
import { expect, test, vi } from "vitest";
import { createParaglide } from "../create-paraglide.js";
test("matching by strategy works", async () => {
    const baseLocale = "en";
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale,
                locales: ["en", "de"],
            },
        }),
        strategy: ["cookie", "baseLocale"],
        cookieName: "PARAGLIDE_LOCALE",
    });
    // @ts-expect-error - global variable definition
    globalThis.document = {};
    globalThis.document.cookie = "OTHER_COOKIE=blaba;";
    const locale = runtime.getLocale();
    expect(locale).toBe(baseLocale);
});
test("throws if variable is used without baseLocale as fallback strategy", async () => {
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "de"],
            },
        }),
        strategy: ["globalVariable"],
    });
    expect(() => runtime.getLocale()).toThrow();
    runtime.setLocale("de");
    expect(runtime.getLocale()).toBe("de");
});
test("retrieves the locale for a url pattern", async () => {
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "de"],
            },
        }),
        strategy: ["url"],
        isServer: "false",
        urlPatterns: [
            {
                pattern: "https://example.:tld/:path*",
                localized: [
                    ["en", "https://example.com/:path*"],
                    ["de", "https://example.de/:path*"],
                ],
            },
        ],
    });
    globalThis.window = { location: { href: "https://example.com/page" } };
    expect(runtime.getLocale()).toBe("en");
    globalThis.window = { location: { href: "https://example.de/page" } };
    expect(runtime.getLocale()).toBe("de");
});
test("url pattern strategy doesn't throw during SSR", async () => {
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "de"],
            },
        }),
        strategy: ["url", "baseLocale"],
        urlPatterns: [
            {
                pattern: "https://example.:tld/:path*",
                localized: [
                    ["en", "https://example.com/:path*"],
                    ["de", "https://example.de/:path*"],
                ],
            },
        ],
    });
    expect(() => runtime.getLocale()).not.toThrow();
});
test("doesn't throw for an old cookie locale", async () => {
    const baseLocale = "en";
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "de"],
            },
        }),
        strategy: ["cookie", "baseLocale"],
        cookieName: "PARAGLIDE_LOCALE",
    });
    // @ts-expect-error - global variable definition
    globalThis.document = {};
    globalThis.document.cookie = "PARAGLIDE_LOCALE=fr;";
    const locale = runtime.getLocale();
    expect(locale).toBe(baseLocale);
});
test("returns the preferred locale from navigator.languages", async () => {
    const originalNavigator = globalThis.navigator;
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "fr", "de"],
            },
        }),
        isServer: "false",
        strategy: ["preferredLanguage"],
    });
    // Mock navigator.languages
    Object.defineProperty(globalThis, "navigator", {
        value: {
            languages: ["fr-FR", "en-US", "de"],
        },
        configurable: true,
    });
    expect(runtime.getLocale()).toBe("fr");
    // Restore original navigator
    Object.defineProperty(globalThis, "navigator", {
        value: originalNavigator,
        configurable: true,
    });
});
test("returns the locale from local storage", async () => {
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "de"],
            },
        }),
        strategy: ["localStorage"],
        localStorageKey: "PARAGLIDE_LOCALE",
        isServer: "false",
    });
    // @ts-expect-error - global variable definition
    globalThis.localStorage = {
        setItem: vi.fn(),
        getItem: vi.fn(() => "de"),
    };
    expect(runtime.getLocale()).toBe("de");
});
test("initially sets the locale after resolving it for the first time", async () => {
    // Create runtime with multiple strategies
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "de", "fr"],
            },
        }),
        strategy: ["url", "cookie"],
        isServer: "false",
        cookieName: "PARAGLIDE_LOCALE",
        urlPatterns: [
            {
                pattern: "https://example.com/:path*",
                localized: [
                    ["en", "https://example.com/en/:path*"],
                    ["de", "https://example.com/de/:path*"],
                    ["fr", "https://example.com/fr/:path*"],
                ],
            },
        ],
    });
    // Setup global objects for URL strategy
    globalThis.window = {
        // @ts-expect-error - global variable definition
        location: {
            hostname: "example.com",
            href: "https://example.com/de/page",
        },
    };
    // Create a spy on the internal _locale variable to verify it was set
    // We can do this by checking if setLocale works without explicitly setting it first
    // @ts-expect-error - global variable definition
    globalThis.document = { cookie: "" };
    // First call to getLocale should resolve and set the locale
    expect(runtime.getLocale()).toBe("de");
    // Cookie should be set, proving that the locale was initially set
    expect(globalThis.document.cookie).toBe("PARAGLIDE_LOCALE=de; path=/; max-age=34560000; domain=example.com");
    expect(globalThis.window.location.href).toBe("https://example.com/de/page");
});
test("returns locale from custom strategy", async () => {
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "fr", "de"],
            },
        }),
        strategy: ["custom-client", "baseLocale"],
        isServer: "false",
    });
    runtime.defineCustomClientStrategy("custom-client", {
        getLocale: () => "fr",
        setLocale: () => { },
    });
    const locale = runtime.getLocale();
    expect(locale).toBe("fr");
});
test("falls back to next strategy when custom strategy returns undefined", async () => {
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "fr"],
            },
        }),
        strategy: ["custom-undefined", "baseLocale"],
        isServer: "false",
    });
    runtime.defineCustomClientStrategy("custom-undefined", {
        getLocale: () => undefined,
        setLocale: () => { },
    });
    const locale = runtime.getLocale();
    expect(locale).toBe("en"); // Should fall back to baseLocale
});
test("throws error if custom strategy returns invalid locale", async () => {
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "fr"],
            },
        }),
        strategy: ["custom-invalid", "baseLocale"],
        isServer: "false",
    });
    runtime.defineCustomClientStrategy("custom-invalid", {
        getLocale: () => "invalid-locale",
        setLocale: () => { },
    });
    expect(() => runtime.getLocale()).toThrow();
});
test("custom strategy takes precedence over built-in strategies in getLocale", async () => {
    // @ts-expect-error - global variable definition
    globalThis.document = { cookie: "PARAGLIDE_LOCALE=fr" };
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "fr", "de"],
            },
        }),
        strategy: ["custom-priority", "cookie", "baseLocale"],
        cookieName: "PARAGLIDE_LOCALE",
        isServer: "false",
    });
    runtime.defineCustomClientStrategy("custom-priority", {
        getLocale: () => "de",
        setLocale: () => { },
    });
    const locale = runtime.getLocale();
    expect(locale).toBe("de"); // Should use custom strategy, not cookie
});
test("multiple custom strategies work in order in getLocale", async () => {
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "fr", "de"],
            },
        }),
        strategy: ["custom-first", "custom-second", "baseLocale"],
        isServer: "false",
    });
    // Define two custom strategies
    runtime.defineCustomClientStrategy("custom-first", {
        getLocale: () => undefined, // This one returns undefined
        setLocale: () => { },
    });
    runtime.defineCustomClientStrategy("custom-second", {
        getLocale: () => "fr", // This one returns a locale
        setLocale: () => { },
    });
    const locale = runtime.getLocale();
    expect(locale).toBe("fr"); // Should use second custom strategy
});
test("custom strategy works with session storage simulation", async () => {
    // Simulate a custom strategy that reads from session storage
    let sessionData = "de";
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "fr", "de"],
            },
        }),
        strategy: ["custom-session", "baseLocale"],
        isServer: "false",
    });
    runtime.defineCustomClientStrategy("custom-session", {
        getLocale: () => sessionData,
        setLocale: (locale) => {
            sessionData = locale;
        },
    });
    const locale = runtime.getLocale();
    expect(locale).toBe("de");
});
test("custom strategy integrates with locale initialization", async () => {
    // @ts-expect-error - global variable definition
    globalThis.window = {};
    // Define a custom strategy that tracks if it was called
    let getLocaleCalled = false;
    let setLocaleCalled = false;
    const runtime = await createParaglide({
        blob: await newProject({
            settings: {
                baseLocale: "en",
                locales: ["en", "fr", "de"],
            },
        }),
        strategy: ["custom-tracking"],
        isServer: "false",
    });
    runtime.defineCustomClientStrategy("custom-tracking", {
        getLocale: () => {
            getLocaleCalled = true;
            return "fr";
        },
        setLocale: () => {
            setLocaleCalled = true;
        },
    });
    // First call should trigger the custom strategy
    const locale = runtime.getLocale();
    expect(locale).toBe("fr");
    expect(getLocaleCalled).toBe(true);
    // Setting the locale should also call the custom strategy
    runtime.setLocale("de");
    // The locale should be set internally after first resolution
    expect(setLocaleCalled).toBe(true);
});