codekingpro/portable-devtools

1import Diff from './base.js';
2import { generateOptions } from '../util/params.js';
3class LineDiff extends Diff {
4    constructor() {
5        super(...arguments);
6        this.tokenize = tokenize;
7    }
8    equals(left, right, options) {
9        // If we're ignoring whitespace, we need to normalise lines by stripping
10        // whitespace before checking equality. (This has an annoying interaction
11        // with newlineIsToken that requires special handling: if newlines get their
12        // own token, then we DON'T want to trim the *newline* tokens down to empty
13        // strings, since this would cause us to treat whitespace-only line content
14        // as equal to a separator between lines, which would be weird and
15        // inconsistent with the documented behavior of the options.)
16        if (options.ignoreWhitespace) {
17            if (!options.newlineIsToken || !left.includes('\n')) {
18                left = left.trim();
19            }
20            if (!options.newlineIsToken || !right.includes('\n')) {
21                right = right.trim();
22            }
23        }
24        else if (options.ignoreNewlineAtEof && !options.newlineIsToken) {
25            if (left.endsWith('\n')) {
26                left = left.slice(0, -1);
27            }
28            if (right.endsWith('\n')) {
29                right = right.slice(0, -1);
30            }
31        }
32        return super.equals(left, right, options);
33    }
34}
35export const lineDiff = new LineDiff();
36export function diffLines(oldStr, newStr, options) {
37    return lineDiff.diff(oldStr, newStr, options);
38}
39export function diffTrimmedLines(oldStr, newStr, options) {
40    options = generateOptions(options, { ignoreWhitespace: true });
41    return lineDiff.diff(oldStr, newStr, options);
42}
43// Exported standalone so it can be used from jsonDiff too.
44export function tokenize(value, options) {
45    if (options.stripTrailingCr) {
46        // remove one \r before \n to match GNU diff's --strip-trailing-cr behavior
47        value = value.replace(/\r\n/g, '\n');
48    }
49    const retLines = [], linesAndNewlines = value.split(/(\n|\r\n)/);
50    // Ignore the final empty token that occurs if the string ends with a new line
51    if (!linesAndNewlines[linesAndNewlines.length - 1]) {
52        linesAndNewlines.pop();
53    }
54    // Merge the content and line separators into single tokens
55    for (let i = 0; i < linesAndNewlines.length; i++) {
56        const line = linesAndNewlines[i];
57        if (i % 2 && !options.newlineIsToken) {
58            retLines[retLines.length - 1] += line;
59        }
60        else {
61            retLines.push(line);
62        }
63    }
64    return retLines;
65}
66