import { describe, expect, it } from "vitest";
import { languageIdFor } from "./language.js";

describe("languageIdFor", () => {
  it("maps Kotlin extensions", () => {
    expect(languageIdFor("src/Main.kt")).toBe("kotlin");
    expect(languageIdFor("script.kts")).toBe("kotlin");
  });

  it("maps TypeScript, Rust, Python and Go", () => {
    expect(languageIdFor("a.ts")).toBe("typescript");
    expect(languageIdFor("a.tsx")).toBe("typescriptreact");
    expect(languageIdFor("lib.rs")).toBe("rust");
    expect(languageIdFor("main.py")).toBe("python");
    expect(languageIdFor("main.go")).toBe("go");
  });

  it("falls back to plaintext for unknown extensions", () => {
    expect(languageIdFor("a.xyz")).toBe("plaintext");
  });

  it("falls back to plaintext for files without an extension", () => {
    expect(languageIdFor("Makefile")).toBe("plaintext");
  });

  it("uses the last extension for dotted paths", () => {
    expect(languageIdFor("component.test.ts")).toBe("typescript");
  });
});