Function testDiffContextLines

packages/jest-diff/src/__tests__/diff.test.ts:706–731

(contextLines?: number)

describe('context', () => {
  const testDiffContextLines = (contextLines?: number) => {
    const validContextLines =
      typeof contextLines === 'number' &&
      Number.isSafeInteger(contextLines) &&
      contextLines >= 0;

    test(`number of lines: ${
      typeof contextLines === 'number' ? contextLines : 'undefined'
    } ${validContextLines ? '' : '(5 default)'}`, () => {
      const options = {
        ...optionsCounts,
        contextLines,
        expand: false,
      };
      if (!validContextLines) {
        options.patchColor = chalk.dim;
      }

      const result = diff(
        {test: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]},
        {test: [1, 2, 3, 4, 5, 6, 7, 8, 10, 9]},
        options,
      );
      expect(result).toMatchSnapshot();
    });
  };

  testDiffContextLines(-1); // (5 default)
  testDiffContextLines(0);