/
CSSTransformer.js
243 lines (212 loc) Β· 6.65 KB
/
CSSTransformer.js
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
// @flow strict-local
import path from 'path';
import SourceMap from '@parcel/source-map';
import {Transformer} from '@parcel/plugin';
import {
transform,
transformStyleAttribute,
browserslistToTargets,
} from '@parcel/css';
import {remapSourceLocation, relativePath} from '@parcel/utils';
import browserslist from 'browserslist';
import nullthrows from 'nullthrows';
import ThrowableDiagnostic, {errorToDiagnostic} from '@parcel/diagnostic';
export default (new Transformer({
async loadConfig({config, options}) {
let conf = await config.getConfigFrom(options.projectRoot + '/index', [], {
packageKey: '@parcel/transformer-css',
});
return conf?.contents;
},
async transform({asset, config, options}) {
// Normalize the asset's environment so that properties that only affect JS don't cause CSS to be duplicated.
// For example, with ESModule and CommonJS targets, only a single shared CSS bundle should be produced.
let env = asset.env;
asset.setEnvironment({
context: 'browser',
engines: {
browsers: asset.env.engines.browsers,
},
shouldOptimize: asset.env.shouldOptimize,
shouldScopeHoist: asset.env.shouldScopeHoist,
sourceMap: asset.env.sourceMap,
});
let [code, originalMap] = await Promise.all([
asset.getBuffer(),
asset.getMap(),
]);
let targets = getTargets(asset.env.engines.browsers);
let res;
try {
if (asset.meta.type === 'attr') {
res = transformStyleAttribute({
code,
analyzeDependencies: true,
targets,
});
} else {
res = transform({
filename: path.relative(options.projectRoot, asset.filePath),
code,
cssModules:
asset.meta.type !== 'tag' &&
(config?.cssModules ??
(asset.meta.cssModulesCompiled == null &&
/\.module\./.test(asset.filePath))),
analyzeDependencies: asset.meta.hasDependencies !== false,
sourceMap: !!asset.env.sourceMap,
drafts: config?.drafts,
pseudoClasses: config?.pseudoClasses,
targets,
});
}
} catch (err) {
err.filePath = asset.filePath;
let diagnostic = errorToDiagnostic(err, {
origin: '@parcel/transformer-css',
});
if (err.data?.type === 'AmbiguousUrlInCustomProperty' && err.data.url) {
let p =
'/' +
relativePath(
options.projectRoot,
path.resolve(path.dirname(asset.filePath), err.data.url),
false,
);
diagnostic[0].hints = [`Replace with: url(${p})`];
diagnostic[0].documentationURL =
'https://parceljs.org/languages/css/#url()';
}
throw new ThrowableDiagnostic({
diagnostic,
});
}
asset.setBuffer(res.code);
if (res.map != null) {
let vlqMap = JSON.parse(res.map.toString());
let map = new SourceMap(options.projectRoot);
map.addVLQMap(vlqMap);
if (originalMap) {
map.extends(originalMap);
}
asset.setMap(map);
}
if (res.dependencies) {
for (let dep of res.dependencies) {
let loc = dep.loc;
if (originalMap) {
loc = remapSourceLocation(loc, originalMap);
}
if (dep.type === 'import' && !res.exports) {
asset.addDependency({
specifier: dep.url,
specifierType: 'url',
loc,
meta: {
// For the glob resolver to distinguish between `@import` and other URL dependencies.
isCSSImport: true,
media: dep.media,
},
});
} else if (dep.type === 'url') {
asset.addURLDependency(dep.url, {
loc,
meta: {
placeholder: dep.placeholder,
},
});
}
}
}
let assets = [asset];
if (res.exports != null) {
let exports = res.exports;
asset.symbols.ensure();
asset.symbols.set('default', 'default');
let dependencies = new Map();
let locals = new Map();
let c = 0;
let depjs = '';
let js = '';
let jsDeps = [];
for (let key in exports) {
locals.set(exports[key].name, key);
}
let seen = new Set();
let add = key => {
if (seen.has(key)) {
return;
}
seen.add(key);
let e = exports[key];
let s = `module.exports[${JSON.stringify(key)}] = \`${e.name}`;
for (let ref of e.composes) {
s += ' ';
if (ref.type === 'local') {
add(nullthrows(locals.get(ref.name)));
s +=
'${' +
`module.exports[${JSON.stringify(
nullthrows(locals.get(ref.name)),
)}]` +
'}';
} else if (ref.type === 'global') {
s += ref.name;
} else if (ref.type === 'dependency') {
let d = dependencies.get(ref.specifier);
if (d == null) {
d = `dep_${c++}`;
depjs += `import * as ${d} from ${JSON.stringify(
ref.specifier,
)};\n`;
dependencies.set(ref.specifier, d);
}
s += '${' + `${d}[${JSON.stringify(ref.name)}]` + '}';
}
}
s += '`;\n';
// If the export is referenced internally (e.g. used @keyframes), add a self-reference
// to the JS so the symbol is retained during tree-shaking.
if (e.isReferenced) {
s += `module.exports[${JSON.stringify(key)}];\n`;
}
js += s;
};
for (let key in exports) {
asset.symbols.set(key, exports[key].name);
add(key);
}
if (res.dependencies) {
for (let dep of res.dependencies) {
if (dep.type === 'import') {
// TODO: Figure out how to treeshake this
let d = `dep_$${c++}`;
depjs += `import * as ${d} from ${JSON.stringify(dep.url)};\n`;
js += `for (let key in ${d}) { if (key in module.exports) module.exports[key] += ' ' + ${d}[key]; else module.exports[key] = ${d}[key]; }\n`;
asset.symbols.set('*', '*');
}
}
}
assets.push({
type: 'js',
content: depjs + js,
dependencies: jsDeps,
env,
});
}
return assets;
},
}): Transformer);
let cache = new Map();
function getTargets(browsers) {
if (browsers == null) {
return undefined;
}
let cached = cache.get(browsers);
if (cached != null) {
return cached;
}
let targets = browserslistToTargets(browserslist(browsers));
cache.set(browsers, targets);
return targets;
}