diffLines.js 5.74 KB
'use strict';

Object.defineProperty(exports, '__esModule', {
  value: true
});
exports.printDiffLines =
  exports.diffLinesUnified2 =
  exports.diffLinesUnified =
  exports.diffLinesRaw =
    void 0;

var _diffSequences = _interopRequireDefault(require('diff-sequences'));

var _cleanupSemantic = require('./cleanupSemantic');

var _joinAlignedDiffs = require('./joinAlignedDiffs');

var _normalizeDiffOptions = require('./normalizeDiffOptions');

function _interopRequireDefault(obj) {
  return obj && obj.__esModule ? obj : {default: obj};
}

/**
 * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */
const isEmptyString = lines => lines.length === 1 && lines[0].length === 0;

const countChanges = diffs => {
  let a = 0;
  let b = 0;
  diffs.forEach(diff => {
    switch (diff[0]) {
      case _cleanupSemantic.DIFF_DELETE:
        a += 1;
        break;

      case _cleanupSemantic.DIFF_INSERT:
        b += 1;
        break;
    }
  });
  return {
    a,
    b
  };
};

const printAnnotation = (
  {
    aAnnotation,
    aColor,
    aIndicator,
    bAnnotation,
    bColor,
    bIndicator,
    includeChangeCounts,
    omitAnnotationLines
  },
  changeCounts
) => {
  if (omitAnnotationLines) {
    return '';
  }

  let aRest = '';
  let bRest = '';

  if (includeChangeCounts) {
    const aCount = String(changeCounts.a);
    const bCount = String(changeCounts.b); // Padding right aligns the ends of the annotations.

    const baAnnotationLengthDiff = bAnnotation.length - aAnnotation.length;
    const aAnnotationPadding = ' '.repeat(Math.max(0, baAnnotationLengthDiff));
    const bAnnotationPadding = ' '.repeat(Math.max(0, -baAnnotationLengthDiff)); // Padding left aligns the ends of the counts.

    const baCountLengthDiff = bCount.length - aCount.length;
    const aCountPadding = ' '.repeat(Math.max(0, baCountLengthDiff));
    const bCountPadding = ' '.repeat(Math.max(0, -baCountLengthDiff));
    aRest =
      aAnnotationPadding + '  ' + aIndicator + ' ' + aCountPadding + aCount;
    bRest =
      bAnnotationPadding + '  ' + bIndicator + ' ' + bCountPadding + bCount;
  }

  return (
    aColor(aIndicator + ' ' + aAnnotation + aRest) +
    '\n' +
    bColor(bIndicator + ' ' + bAnnotation + bRest) +
    '\n\n'
  );
};

const printDiffLines = (diffs, options) =>
  printAnnotation(options, countChanges(diffs)) +
  (options.expand
    ? (0, _joinAlignedDiffs.joinAlignedDiffsExpand)(diffs, options)
    : (0, _joinAlignedDiffs.joinAlignedDiffsNoExpand)(diffs, options)); // Compare two arrays of strings line-by-line. Format as comparison lines.

exports.printDiffLines = printDiffLines;

const diffLinesUnified = (aLines, bLines, options) =>
  printDiffLines(
    diffLinesRaw(
      isEmptyString(aLines) ? [] : aLines,
      isEmptyString(bLines) ? [] : bLines
    ),
    (0, _normalizeDiffOptions.normalizeDiffOptions)(options)
  ); // Given two pairs of arrays of strings:
// Compare the pair of comparison arrays line-by-line.
// Format the corresponding lines in the pair of displayable arrays.

exports.diffLinesUnified = diffLinesUnified;

const diffLinesUnified2 = (
  aLinesDisplay,
  bLinesDisplay,
  aLinesCompare,
  bLinesCompare,
  options
) => {
  if (isEmptyString(aLinesDisplay) && isEmptyString(aLinesCompare)) {
    aLinesDisplay = [];
    aLinesCompare = [];
  }

  if (isEmptyString(bLinesDisplay) && isEmptyString(bLinesCompare)) {
    bLinesDisplay = [];
    bLinesCompare = [];
  }

  if (
    aLinesDisplay.length !== aLinesCompare.length ||
    bLinesDisplay.length !== bLinesCompare.length
  ) {
    // Fall back to diff of display lines.
    return diffLinesUnified(aLinesDisplay, bLinesDisplay, options);
  }

  const diffs = diffLinesRaw(aLinesCompare, bLinesCompare); // Replace comparison lines with displayable lines.

  let aIndex = 0;
  let bIndex = 0;
  diffs.forEach(diff => {
    switch (diff[0]) {
      case _cleanupSemantic.DIFF_DELETE:
        diff[1] = aLinesDisplay[aIndex];
        aIndex += 1;
        break;

      case _cleanupSemantic.DIFF_INSERT:
        diff[1] = bLinesDisplay[bIndex];
        bIndex += 1;
        break;

      default:
        diff[1] = bLinesDisplay[bIndex];
        aIndex += 1;
        bIndex += 1;
    }
  });
  return printDiffLines(
    diffs,
    (0, _normalizeDiffOptions.normalizeDiffOptions)(options)
  );
}; // Compare two arrays of strings line-by-line.

exports.diffLinesUnified2 = diffLinesUnified2;

const diffLinesRaw = (aLines, bLines) => {
  const aLength = aLines.length;
  const bLength = bLines.length;

  const isCommon = (aIndex, bIndex) => aLines[aIndex] === bLines[bIndex];

  const diffs = [];
  let aIndex = 0;
  let bIndex = 0;

  const foundSubsequence = (nCommon, aCommon, bCommon) => {
    for (; aIndex !== aCommon; aIndex += 1) {
      diffs.push(
        new _cleanupSemantic.Diff(_cleanupSemantic.DIFF_DELETE, aLines[aIndex])
      );
    }

    for (; bIndex !== bCommon; bIndex += 1) {
      diffs.push(
        new _cleanupSemantic.Diff(_cleanupSemantic.DIFF_INSERT, bLines[bIndex])
      );
    }

    for (; nCommon !== 0; nCommon -= 1, aIndex += 1, bIndex += 1) {
      diffs.push(
        new _cleanupSemantic.Diff(_cleanupSemantic.DIFF_EQUAL, bLines[bIndex])
      );
    }
  };

  (0, _diffSequences.default)(aLength, bLength, isCommon, foundSubsequence); // After the last common subsequence, push remaining change items.

  for (; aIndex !== aLength; aIndex += 1) {
    diffs.push(
      new _cleanupSemantic.Diff(_cleanupSemantic.DIFF_DELETE, aLines[aIndex])
    );
  }

  for (; bIndex !== bLength; bIndex += 1) {
    diffs.push(
      new _cleanupSemantic.Diff(_cleanupSemantic.DIFF_INSERT, bLines[bIndex])
    );
  }

  return diffs;
};

exports.diffLinesRaw = diffLinesRaw;