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-rw-r--r--vanilla/node_modules/css-tree/lib/syntax/node/UnicodeRange.js156
1 files changed, 156 insertions, 0 deletions
diff --git a/vanilla/node_modules/css-tree/lib/syntax/node/UnicodeRange.js b/vanilla/node_modules/css-tree/lib/syntax/node/UnicodeRange.js
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index 0000000..95ee8b9
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+++ b/vanilla/node_modules/css-tree/lib/syntax/node/UnicodeRange.js
@@ -0,0 +1,156 @@
+import {
+ isHexDigit,
+ Ident,
+ Number,
+ Dimension
+} from '../../tokenizer/index.js';
+
+const PLUSSIGN = 0x002B; // U+002B PLUS SIGN (+)
+const HYPHENMINUS = 0x002D; // U+002D HYPHEN-MINUS (-)
+const QUESTIONMARK = 0x003F; // U+003F QUESTION MARK (?)
+
+function eatHexSequence(offset, allowDash) {
+ let len = 0;
+
+ for (let pos = this.tokenStart + offset; pos < this.tokenEnd; pos++) {
+ const code = this.charCodeAt(pos);
+
+ if (code === HYPHENMINUS && allowDash && len !== 0) {
+ eatHexSequence.call(this, offset + len + 1, false);
+ return -1;
+ }
+
+ if (!isHexDigit(code)) {
+ this.error(
+ allowDash && len !== 0
+ ? 'Hyphen minus' + (len < 6 ? ' or hex digit' : '') + ' is expected'
+ : (len < 6 ? 'Hex digit is expected' : 'Unexpected input'),
+ pos
+ );
+ }
+
+ if (++len > 6) {
+ this.error('Too many hex digits', pos);
+ };
+ }
+
+ this.next();
+ return len;
+}
+
+function eatQuestionMarkSequence(max) {
+ let count = 0;
+
+ while (this.isDelim(QUESTIONMARK)) {
+ if (++count > max) {
+ this.error('Too many question marks');
+ }
+
+ this.next();
+ }
+}
+
+function startsWith(code) {
+ if (this.charCodeAt(this.tokenStart) !== code) {
+ this.error((code === PLUSSIGN ? 'Plus sign' : 'Hyphen minus') + ' is expected');
+ }
+}
+
+// https://drafts.csswg.org/css-syntax/#urange
+// Informally, the <urange> production has three forms:
+// U+0001
+// Defines a range consisting of a single code point, in this case the code point "1".
+// U+0001-00ff
+// Defines a range of codepoints between the first and the second value, in this case
+// the range between "1" and "ff" (255 in decimal) inclusive.
+// U+00??
+// Defines a range of codepoints where the "?" characters range over all hex digits,
+// in this case defining the same as the value U+0000-00ff.
+// In each form, a maximum of 6 digits is allowed for each hexadecimal number (if you treat "?" as a hexadecimal digit).
+//
+// <urange> =
+// u '+' <ident-token> '?'* |
+// u <dimension-token> '?'* |
+// u <number-token> '?'* |
+// u <number-token> <dimension-token> |
+// u <number-token> <number-token> |
+// u '+' '?'+
+function scanUnicodeRange() {
+ let hexLength = 0;
+
+ switch (this.tokenType) {
+ case Number:
+ // u <number-token> '?'*
+ // u <number-token> <dimension-token>
+ // u <number-token> <number-token>
+ hexLength = eatHexSequence.call(this, 1, true);
+
+ if (this.isDelim(QUESTIONMARK)) {
+ eatQuestionMarkSequence.call(this, 6 - hexLength);
+ break;
+ }
+
+ if (this.tokenType === Dimension ||
+ this.tokenType === Number) {
+ startsWith.call(this, HYPHENMINUS);
+ eatHexSequence.call(this, 1, false);
+ break;
+ }
+
+ break;
+
+ case Dimension:
+ // u <dimension-token> '?'*
+ hexLength = eatHexSequence.call(this, 1, true);
+
+ if (hexLength > 0) {
+ eatQuestionMarkSequence.call(this, 6 - hexLength);
+ }
+
+ break;
+
+ default:
+ // u '+' <ident-token> '?'*
+ // u '+' '?'+
+ this.eatDelim(PLUSSIGN);
+
+ if (this.tokenType === Ident) {
+ hexLength = eatHexSequence.call(this, 0, true);
+ if (hexLength > 0) {
+ eatQuestionMarkSequence.call(this, 6 - hexLength);
+ }
+ break;
+ }
+
+ if (this.isDelim(QUESTIONMARK)) {
+ this.next();
+ eatQuestionMarkSequence.call(this, 5);
+ break;
+ }
+
+ this.error('Hex digit or question mark is expected');
+ }
+}
+
+export const name = 'UnicodeRange';
+export const structure = {
+ value: String
+};
+
+export function parse() {
+ const start = this.tokenStart;
+
+ // U or u
+ this.eatIdent('u');
+ scanUnicodeRange.call(this);
+
+ return {
+ type: 'UnicodeRange',
+ loc: this.getLocation(start, this.tokenStart),
+ value: this.substrToCursor(start)
+ };
+}
+
+export function generate(node) {
+ this.tokenize(node.value);
+}