pdf.js/test/unit/core_utils_spec.js

/* Copyright 2019 Mozilla Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import { Dict, Ref } from "../../src/core/primitives.js";
import {
  getInheritableProperty,
  isWhiteSpace,
  log2,
  toRomanNumerals,
} from "../../src/core/core_utils.js";
import { XRefMock } from "./test_utils.js";

describe("core_utils", function () {
  describe("getInheritableProperty", function () {
    it("handles non-dictionary arguments", function () {
      expect(getInheritableProperty({ dict: null, key: "foo" })).toEqual(
        undefined
      );
      expect(getInheritableProperty({ dict: undefined, key: "foo" })).toEqual(
        undefined
      );
    });

    it("handles dictionaries that do not contain the property", function () {
      // Empty dictionary.
      const emptyDict = new Dict();
      expect(getInheritableProperty({ dict: emptyDict, key: "foo" })).toEqual(
        undefined
      );

      // Filled dictionary with a different property.
      const filledDict = new Dict();
      filledDict.set("bar", "baz");
      expect(getInheritableProperty({ dict: filledDict, key: "foo" })).toEqual(
        undefined
      );
    });

    it("fetches the property if it is not inherited", function () {
      const ref = Ref.get(10, 0);
      const xref = new XRefMock([{ ref, data: "quux" }]);
      const dict = new Dict(xref);

      // Regular values should be fetched.
      dict.set("foo", "bar");
      expect(getInheritableProperty({ dict, key: "foo" })).toEqual("bar");

      // Array value should be fetched (with references resolved).
      dict.set("baz", ["qux", ref]);
      expect(
        getInheritableProperty({ dict, key: "baz", getArray: true })
      ).toEqual(["qux", "quux"]);
    });

    it("fetches the property if it is inherited and present on one level", function () {
      const ref = Ref.get(10, 0);
      const xref = new XRefMock([{ ref, data: "quux" }]);
      const firstDict = new Dict(xref);
      const secondDict = new Dict(xref);
      firstDict.set("Parent", secondDict);

      // Regular values should be fetched.
      secondDict.set("foo", "bar");
      expect(getInheritableProperty({ dict: firstDict, key: "foo" })).toEqual(
        "bar"
      );

      // Array value should be fetched (with references resolved).
      secondDict.set("baz", ["qux", ref]);
      expect(
        getInheritableProperty({ dict: firstDict, key: "baz", getArray: true })
      ).toEqual(["qux", "quux"]);
    });

    it("fetches the property if it is inherited and present on multiple levels", function () {
      const ref = Ref.get(10, 0);
      const xref = new XRefMock([{ ref, data: "quux" }]);
      const firstDict = new Dict(xref);
      const secondDict = new Dict(xref);
      firstDict.set("Parent", secondDict);

      // Regular values should be fetched.
      firstDict.set("foo", "bar1");
      secondDict.set("foo", "bar2");
      expect(getInheritableProperty({ dict: firstDict, key: "foo" })).toEqual(
        "bar1"
      );
      expect(
        getInheritableProperty({
          dict: firstDict,
          key: "foo",
          getArray: false,
          stopWhenFound: false,
        })
      ).toEqual(["bar1", "bar2"]);

      // Array value should be fetched (with references resolved).
      firstDict.set("baz", ["qux1", ref]);
      secondDict.set("baz", ["qux2", ref]);
      expect(
        getInheritableProperty({
          dict: firstDict,
          key: "baz",
          getArray: true,
          stopWhenFound: false,
        })
      ).toEqual([
        ["qux1", "quux"],
        ["qux2", "quux"],
      ]);
    });

    it("stops searching when the loop limit is reached", function () {
      const dict = new Dict();
      let currentDict = dict;
      let parentDict = null;
      // Exceed the loop limit of 100.
      for (let i = 0; i < 150; i++) {
        parentDict = new Dict();
        currentDict.set("Parent", parentDict);
        currentDict = parentDict;
      }
      parentDict.set("foo", "bar"); // Never found because of loop limit.
      expect(getInheritableProperty({ dict, key: "foo" })).toEqual(undefined);

      dict.set("foo", "baz");
      expect(
        getInheritableProperty({
          dict,
          key: "foo",
          getArray: false,
          stopWhenFound: false,
        })
      ).toEqual(["baz"]);
    });
  });

  describe("toRomanNumerals", function () {
    it("handles invalid arguments", function () {
      for (const input of ["foo", -1, 0]) {
        expect(function () {
          toRomanNumerals(input);
        }).toThrow(new Error("The number should be a positive integer."));
      }
    });

    it("converts numbers to uppercase Roman numerals", function () {
      expect(toRomanNumerals(1)).toEqual("I");
      expect(toRomanNumerals(6)).toEqual("VI");
      expect(toRomanNumerals(7)).toEqual("VII");
      expect(toRomanNumerals(8)).toEqual("VIII");
      expect(toRomanNumerals(10)).toEqual("X");
      expect(toRomanNumerals(40)).toEqual("XL");
      expect(toRomanNumerals(100)).toEqual("C");
      expect(toRomanNumerals(500)).toEqual("D");
      expect(toRomanNumerals(1000)).toEqual("M");
      expect(toRomanNumerals(2019)).toEqual("MMXIX");
    });

    it("converts numbers to lowercase Roman numerals", function () {
      expect(toRomanNumerals(1, /* lowercase = */ true)).toEqual("i");
      expect(toRomanNumerals(6, /* lowercase = */ true)).toEqual("vi");
      expect(toRomanNumerals(7, /* lowercase = */ true)).toEqual("vii");
      expect(toRomanNumerals(8, /* lowercase = */ true)).toEqual("viii");
      expect(toRomanNumerals(10, /* lowercase = */ true)).toEqual("x");
      expect(toRomanNumerals(40, /* lowercase = */ true)).toEqual("xl");
      expect(toRomanNumerals(100, /* lowercase = */ true)).toEqual("c");
      expect(toRomanNumerals(500, /* lowercase = */ true)).toEqual("d");
      expect(toRomanNumerals(1000, /* lowercase = */ true)).toEqual("m");
      expect(toRomanNumerals(2019, /* lowercase = */ true)).toEqual("mmxix");
    });
  });

  describe("log2", function () {
    it("handles values smaller than/equal to zero", function () {
      expect(log2(0)).toEqual(0);
      expect(log2(-1)).toEqual(0);
    });

    it("handles values larger than zero", function () {
      expect(log2(1)).toEqual(0);
      expect(log2(2)).toEqual(1);
      expect(log2(3)).toEqual(2);
      expect(log2(3.14)).toEqual(2);
    });
  });

  describe("isWhiteSpace", function () {
    it("handles space characters", function () {
      expect(isWhiteSpace(0x20)).toEqual(true);
      expect(isWhiteSpace(0x09)).toEqual(true);
      expect(isWhiteSpace(0x0d)).toEqual(true);
      expect(isWhiteSpace(0x0a)).toEqual(true);
    });

    it("handles non-space characters", function () {
      expect(isWhiteSpace(0x0b)).toEqual(false);
      expect(isWhiteSpace(null)).toEqual(false);
      expect(isWhiteSpace(undefined)).toEqual(false);
    });
  });
});