babel/experimental/babel-preset-env/test/index.js

"use strict";

const babelPresetEnv = require("../lib/index.js");
const assert = require("assert");

const {
  validateModulesOption,
  validateLooseOption
} = babelPresetEnv;

describe("babel-preset-env", () => {
  describe("isPluginRequired", () => {
    it("returns true if no targets are specified", () => {
      const isRequired = babelPresetEnv.isPluginRequired({}, {});
      assert(isRequired);
    });

    it("returns true if plugin feature is not implemented in one or more targets", () => {
      let targets;
      const plugin = {
        edge: false,
        firefox: 45,
        chrome: 49,
      };

      targets = {
        "chrome": Number.MAX_SAFE_INTEGER,
        "firefox": Number.MAX_SAFE_INTEGER
      };
      assert(babelPresetEnv.isPluginRequired(targets, plugin) === false);

      targets = {
        "edge": 12,
      };
      assert(babelPresetEnv.isPluginRequired(plugin, plugin) === true);
    });

    it("returns false if plugin feature is implemented by lower than target", () => {
      const plugin = {
        chrome: 49,
      };
      const targets = {
        "chrome": Number.MAX_SAFE_INTEGER,
      };
      assert(babelPresetEnv.isPluginRequired(targets, plugin) === false);
    });

    it("returns false if plugin feature is implemented is equal to target", () => {
      const plugin = {
        chrome: 49,
      };
      const targets = {
        "chrome": 49,
      };
      assert(babelPresetEnv.isPluginRequired(targets, plugin) === false);
    });

    it("returns true if plugin feature is implemented is greater than target", () => {
      const plugin = {
        chrome: 50,
      };
      const targets = {
        "chrome": 49,
      };
      assert(babelPresetEnv.isPluginRequired(targets, plugin) === true);
    });

    it("returns false if plugin feature is implemented by lower than target defined in browsers query", () => {
      const plugin = {
        chrome: 49,
      };
      const targets = {
        "browsers": "chrome > 50"
      };
      assert(babelPresetEnv.isPluginRequired(targets, plugin) === false);
    });

    it("returns true if plugin feature is implemented is greater than target defined in browsers query", () => {
      const plugin = {
        chrome: 52,
      };
      const targets = {
        "browsers": "chrome > 50"
      };
      assert(babelPresetEnv.isPluginRequired(targets, plugin) === true);
    });

    it("returns true if target's root items overrides versions defined in browsers query", () => {
      const plugin = {
        chrome: 45,
      };
      const targets = {
        browsers: "last 2 Chrome versions",
        chrome: 44
      };

      assert(babelPresetEnv.isPluginRequired(targets, plugin) === true);
    });

    it("doesn't throw when specifiying a decimal for node", () => {
      let targets;
      const plugin = {
        node: 6
      };

      targets = {
        "node": 6.5
      };

      assert.doesNotThrow(() => {
        babelPresetEnv.isPluginRequired(targets, plugin);
      }, Error);
    });
  });

  describe("validateLooseOption", () => {
    it("`undefined` option returns false", () => {
      assert(validateLooseOption() === false);
    });

    it("`false` option returns false", () => {
      assert(validateLooseOption(false) === false);
    });

    it("`true` option returns true", () => {
      assert(validateLooseOption(true) === true);
    });

    it("array option is invalid", () => {
      assert.throws(() => {
        validateModulesOption([]);
      }, Error);
    });
  });

  describe("validateModulesOption", () => {
    it("`undefined` option returns commonjs", () => {
      assert(validateModulesOption() === "commonjs");
    });

    it("`false` option returns commonjs", () => {
      assert(validateModulesOption(false) === false);
    });

    it("commonjs option is valid", () => {
      assert(validateModulesOption("commonjs") === "commonjs");
    });

    it("systemjs option is valid", () => {
      assert(validateModulesOption("systemjs") === "systemjs");
    });

    it("amd option is valid", () => {
      assert(validateModulesOption("amd") === "amd");
    });

    it("umd option is valid", () => {
      assert(validateModulesOption("umd") === "umd");
    });

    it("`true` option is invalid", () => {
      assert.throws(() => {
        validateModulesOption(true);
      }, Error);
    });

    it("array option is invalid", () => {
      assert.throws(() => {
        assert(validateModulesOption([]));
      }, Error);
    });
  });
});