source: trip-planner-front/node_modules/postcss-merge-rules/dist/index.js@ b738035

Last change on this file since b738035 was 6a3a178, checked in by Ema <ema_spirova@…>, 3 years ago

initial commit

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File size: 9.9 KB
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[6a3a178]1"use strict";
2
3Object.defineProperty(exports, "__esModule", {
4 value: true
5});
6exports.default = void 0;
7
8var _browserslist = _interopRequireDefault(require("browserslist"));
9
10var _cssnanoUtils = require("cssnano-utils");
11
12var _ensureCompatibility = require("./lib/ensureCompatibility");
13
14function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
15
16/**
17 * @param {postcss.Declaration} a
18 * @param {postcss.Declaration} b
19 * @return {boolean}
20 */
21function declarationIsEqual(a, b) {
22 return a.important === b.important && a.prop === b.prop && a.value === b.value;
23}
24/**
25 * @param {postcss.Declaration[]} array
26 * @param {postcss.Declaration} decl
27 * @return {number}
28 */
29
30
31function indexOfDeclaration(array, decl) {
32 return array.findIndex(d => declarationIsEqual(d, decl));
33}
34/**
35 * Returns filtered array of matched or unmatched declarations
36 * @param {postcss.Declaration[]} a
37 * @param {postcss.Declaration[]} b
38 * @param {boolean} [not=false]
39 * @return {postcss.Declaration[]}
40 */
41
42
43function intersect(a, b, not) {
44 return a.filter(c => {
45 const index = ~indexOfDeclaration(b, c);
46 return not ? !index : index;
47 });
48}
49/**
50 * @param {postcss.Declaration[]} a
51 * @param {postcss.Declaration[]} b
52 * @return {boolean}
53 */
54
55
56function sameDeclarationsAndOrder(a, b) {
57 if (a.length !== b.length) {
58 return false;
59 }
60
61 return a.every((d, index) => declarationIsEqual(d, b[index]));
62}
63/**
64 * @param {postcss.Rule} ruleA
65 * @param {postcss.Rule} ruleB
66 * @param {string[]=} browsers
67 * @param {Object.<string, boolean>=} compatibilityCache
68 * @return {boolean}
69 */
70
71
72function canMerge(ruleA, ruleB, browsers, compatibilityCache) {
73 const a = ruleA.selectors;
74 const b = ruleB.selectors;
75 const selectors = a.concat(b);
76
77 if (!(0, _ensureCompatibility.ensureCompatibility)(selectors, browsers, compatibilityCache)) {
78 return false;
79 }
80
81 const parent = (0, _cssnanoUtils.sameParent)(ruleA, ruleB);
82 const {
83 name
84 } = ruleA.parent;
85
86 if (parent && name && ~name.indexOf('keyframes')) {
87 return false;
88 }
89
90 return parent && (selectors.every(_ensureCompatibility.noVendor) || (0, _ensureCompatibility.sameVendor)(a, b));
91}
92/**
93 * @param {postcss.Rule} rule
94 * @return {postcss.Declaration[]}
95 */
96
97
98function getDecls(rule) {
99 return rule.nodes.filter(node => node.type === 'decl');
100}
101
102const joinSelectors = (...rules) => rules.map(s => s.selector).join();
103
104function ruleLength(...rules) {
105 return rules.map(r => r.nodes.length ? String(r) : '').join('').length;
106}
107/**
108 * @param {string} prop
109 * @return {{prefix: string, base:string, rest:string[]}}
110 */
111
112
113function splitProp(prop) {
114 // Treat vendor prefixed properties as if they were unprefixed;
115 // moving them when combined with non-prefixed properties can
116 // cause issues. e.g. moving -webkit-background-clip when there
117 // is a background shorthand definition.
118 const parts = prop.split('-');
119
120 if (prop[0] !== '-') {
121 return {
122 prefix: '',
123 base: parts[0],
124 rest: parts.slice(1)
125 };
126 } // Don't split css variables
127
128
129 if (prop[1] === '-') {
130 return {
131 prefix: null,
132 base: null,
133 rest: [prop]
134 };
135 } // Found prefix
136
137
138 return {
139 prefix: parts[1],
140 base: parts[2],
141 rest: parts.slice(3)
142 };
143}
144/**
145 * @param {string} propA
146 * @param {string} propB
147 */
148
149
150function isConflictingProp(propA, propB) {
151 if (propA === propB) {
152 // Same specificity
153 return true;
154 }
155
156 const a = splitProp(propA);
157 const b = splitProp(propB); // Don't resort css variables
158
159 if (!a.base && !b.base) {
160 return true;
161 } // Different base;
162
163
164 if (a.base !== b.base) {
165 return false;
166 } // Conflict if rest-count mismatches
167
168
169 if (a.rest.length !== b.rest.length) {
170 return true;
171 } // Conflict if rest parameters are equal (same but unprefixed)
172
173
174 return a.rest.every((s, index) => b.rest[index] === s);
175}
176/**
177 * @param {postcss.Rule} first
178 * @param {postcss.Rule} second
179 * @return {boolean} merged
180 */
181
182
183function mergeParents(first, second) {
184 // Null check for detached rules
185 if (!first.parent || !second.parent) {
186 return false;
187 } // Check if parents share node
188
189
190 if (first.parent === second.parent) {
191 return false;
192 } // sameParent() already called by canMerge()
193
194
195 second.remove();
196 first.parent.append(second);
197 return true;
198}
199/**
200 * @param {postcss.Rule} first
201 * @param {postcss.Rule} second
202 * @return {postcss.Rule} mergedRule
203 */
204
205
206function partialMerge(first, second) {
207 let intersection = intersect(getDecls(first), getDecls(second));
208
209 if (!intersection.length) {
210 return second;
211 }
212
213 let nextRule = second.next();
214
215 if (!nextRule) {
216 // Grab next cousin
217 const parentSibling = second.parent.next();
218 nextRule = parentSibling && parentSibling.nodes && parentSibling.nodes[0];
219 }
220
221 if (nextRule && nextRule.type === 'rule' && canMerge(second, nextRule)) {
222 let nextIntersection = intersect(getDecls(second), getDecls(nextRule));
223
224 if (nextIntersection.length > intersection.length) {
225 mergeParents(second, nextRule);
226 first = second;
227 second = nextRule;
228 intersection = nextIntersection;
229 }
230 }
231
232 const firstDecls = getDecls(first); // Filter out intersections with later conflicts in First
233
234 intersection = intersection.filter((decl, intersectIndex) => {
235 const indexOfDecl = indexOfDeclaration(firstDecls, decl);
236 const nextConflictInFirst = firstDecls.slice(indexOfDecl + 1).filter(d => isConflictingProp(d.prop, decl.prop));
237
238 if (!nextConflictInFirst.length) {
239 return true;
240 }
241
242 const nextConflictInIntersection = intersection.slice(intersectIndex + 1).filter(d => isConflictingProp(d.prop, decl.prop));
243
244 if (!nextConflictInIntersection.length) {
245 return false;
246 }
247
248 if (nextConflictInFirst.length !== nextConflictInIntersection.length) {
249 return false;
250 }
251
252 return nextConflictInFirst.every((d, index) => declarationIsEqual(d, nextConflictInIntersection[index]));
253 }); // Filter out intersections with previous conflicts in Second
254
255 const secondDecls = getDecls(second);
256 intersection = intersection.filter(decl => {
257 const nextConflictIndex = secondDecls.findIndex(d => isConflictingProp(d.prop, decl.prop));
258
259 if (nextConflictIndex === -1) {
260 return false;
261 }
262
263 if (!declarationIsEqual(secondDecls[nextConflictIndex], decl)) {
264 return false;
265 }
266
267 if (decl.prop.toLowerCase() !== 'direction' && decl.prop.toLowerCase() !== 'unicode-bidi' && secondDecls.some(declaration => declaration.prop.toLowerCase() === 'all')) {
268 return false;
269 }
270
271 secondDecls.splice(nextConflictIndex, 1);
272 return true;
273 });
274
275 if (!intersection.length) {
276 // Nothing to merge
277 return second;
278 }
279
280 const receivingBlock = second.clone();
281 receivingBlock.selector = joinSelectors(first, second);
282 receivingBlock.nodes = [];
283 second.parent.insertBefore(second, receivingBlock);
284 const firstClone = first.clone();
285 const secondClone = second.clone();
286 /**
287 * @param {function(postcss.Declaration):void} callback
288 * @return {function(postcss.Declaration)}
289 */
290
291 function moveDecl(callback) {
292 return decl => {
293 if (~indexOfDeclaration(intersection, decl)) {
294 callback.call(this, decl);
295 }
296 };
297 }
298
299 firstClone.walkDecls(moveDecl(decl => {
300 decl.remove();
301 receivingBlock.append(decl);
302 }));
303 secondClone.walkDecls(moveDecl(decl => decl.remove()));
304 const merged = ruleLength(firstClone, receivingBlock, secondClone);
305 const original = ruleLength(first, second);
306
307 if (merged < original) {
308 first.replaceWith(firstClone);
309 second.replaceWith(secondClone);
310 [firstClone, receivingBlock, secondClone].forEach(r => {
311 if (!r.nodes.length) {
312 r.remove();
313 }
314 });
315
316 if (!secondClone.parent) {
317 return receivingBlock;
318 }
319
320 return secondClone;
321 } else {
322 receivingBlock.remove();
323 return second;
324 }
325}
326/**
327 * @param {string[]} browsers
328 * @param {Object.<string, boolean>} compatibilityCache
329 * @return {function(postcss.Rule)}
330 */
331
332
333function selectorMerger(browsers, compatibilityCache) {
334 /** @type {postcss.Rule} */
335 let cache = null;
336 return function (rule) {
337 // Prime the cache with the first rule, or alternately ensure that it is
338 // safe to merge both declarations before continuing
339 if (!cache || !canMerge(rule, cache, browsers, compatibilityCache)) {
340 cache = rule;
341 return;
342 } // Ensure that we don't deduplicate the same rule; this is sometimes
343 // caused by a partial merge
344
345
346 if (cache === rule) {
347 cache = rule;
348 return;
349 } // Parents merge: check if the rules have same parents, but not same parent nodes
350
351
352 mergeParents(cache, rule); // Merge when declarations are exactly equal
353 // e.g. h1 { color: red } h2 { color: red }
354
355 if (sameDeclarationsAndOrder(getDecls(rule), getDecls(cache))) {
356 rule.selector = joinSelectors(cache, rule);
357 cache.remove();
358 cache = rule;
359 return;
360 } // Merge when both selectors are exactly equal
361 // e.g. a { color: blue } a { font-weight: bold }
362
363
364 if (cache.selector === rule.selector) {
365 const cached = getDecls(cache);
366 rule.walk(decl => {
367 if (~indexOfDeclaration(cached, decl)) {
368 return decl.remove();
369 }
370
371 cache.append(decl);
372 });
373 rule.remove();
374 return;
375 } // Partial merge: check if the rule contains a subset of the last; if
376 // so create a joined selector with the subset, if smaller.
377
378
379 cache = partialMerge(cache, rule);
380 };
381}
382
383function pluginCreator() {
384 return {
385 postcssPlugin: 'postcss-merge-rules',
386
387 prepare(result) {
388 const resultOpts = result.opts || {};
389 const browsers = (0, _browserslist.default)(null, {
390 stats: resultOpts.stats,
391 path: __dirname,
392 env: resultOpts.env
393 });
394 const compatibilityCache = {};
395 return {
396 OnceExit(css) {
397 css.walkRules(selectorMerger(browsers, compatibilityCache));
398 }
399
400 };
401 }
402
403 };
404}
405
406pluginCreator.postcss = true;
407var _default = pluginCreator;
408exports.default = _default;
409module.exports = exports.default;
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