1 files changed, 182 insertions, 0 deletions
diff --git a/vanilla/node_modules/css-tree/lib/generator/token-before.js b/vanilla/node_modules/css-tree/lib/generator/token-before.js
new file mode 100644
index 0000000..da3fed0
--- /dev/null
+++ b/vanilla/node_modules/css-tree/lib/generator/token-before.js
@@ -0,0 +1,182 @@
+import {
+    WhiteSpace,
+    Delim,
+    Ident,
+    Function as FunctionToken,
+    Url,
+    BadUrl,
+    AtKeyword,
+    Hash,
+    Percentage,
+    Dimension,
+    Number as NumberToken,
+    String as StringToken,
+    Colon,
+    LeftParenthesis,
+    RightParenthesis,
+    CDC
+} from '../tokenizer/index.js';
+
+const PLUSSIGN = 0x002B;    // U+002B PLUS SIGN (+)
+const HYPHENMINUS = 0x002D; // U+002D HYPHEN-MINUS (-)
+
+const code = (type, value) => {
+    if (type === Delim) {
+        type = value;
+    }
+
+    if (typeof type === 'string') {
+        const charCode = type.charCodeAt(0);
+        return charCode > 0x7F ? 0x8000 : charCode << 8;
+    }
+
+    return type;
+};
+
+// https://www.w3.org/TR/css-syntax-3/#serialization
+// The only requirement for serialization is that it must "round-trip" with parsing,
+// that is, parsing the stylesheet must produce the same data structures as parsing,
+// serializing, and parsing again, except for consecutive <whitespace-token>s,
+// which may be collapsed into a single token.
+
+const specPairs = [
+    [Ident, Ident],
+    [Ident, FunctionToken],
+    [Ident, Url],
+    [Ident, BadUrl],
+    [Ident, '-'],
+    [Ident, NumberToken],
+    [Ident, Percentage],
+    [Ident, Dimension],
+    [Ident, CDC],
+    [Ident, LeftParenthesis],
+
+    [AtKeyword, Ident],
+    [AtKeyword, FunctionToken],
+    [AtKeyword, Url],
+    [AtKeyword, BadUrl],
+    [AtKeyword, '-'],
+    [AtKeyword, NumberToken],
+    [AtKeyword, Percentage],
+    [AtKeyword, Dimension],
+    [AtKeyword, CDC],
+
+    [Hash, Ident],
+    [Hash, FunctionToken],
+    [Hash, Url],
+    [Hash, BadUrl],
+    [Hash, '-'],
+    [Hash, NumberToken],
+    [Hash, Percentage],
+    [Hash, Dimension],
+    [Hash, CDC],
+
+    [Dimension, Ident],
+    [Dimension, FunctionToken],
+    [Dimension, Url],
+    [Dimension, BadUrl],
+    [Dimension, '-'],
+    [Dimension, NumberToken],
+    [Dimension, Percentage],
+    [Dimension, Dimension],
+    [Dimension, CDC],
+
+    ['#', Ident],
+    ['#', FunctionToken],
+    ['#', Url],
+    ['#', BadUrl],
+    ['#', '-'],
+    ['#', NumberToken],
+    ['#', Percentage],
+    ['#', Dimension],
+    ['#', CDC], // https://github.com/w3c/csswg-drafts/pull/6874
+
+    ['-', Ident],
+    ['-', FunctionToken],
+    ['-', Url],
+    ['-', BadUrl],
+    ['-', '-'],
+    ['-', NumberToken],
+    ['-', Percentage],
+    ['-', Dimension],
+    ['-', CDC], // https://github.com/w3c/csswg-drafts/pull/6874
+
+    [NumberToken, Ident],
+    [NumberToken, FunctionToken],
+    [NumberToken, Url],
+    [NumberToken, BadUrl],
+    [NumberToken, NumberToken],
+    [NumberToken, Percentage],
+    [NumberToken, Dimension],
+    [NumberToken, '%'],
+    [NumberToken, CDC], // https://github.com/w3c/csswg-drafts/pull/6874
+
+    ['@', Ident],
+    ['@', FunctionToken],
+    ['@', Url],
+    ['@', BadUrl],
+    ['@', '-'],
+    ['@', CDC], // https://github.com/w3c/csswg-drafts/pull/6874
+
+    ['.', NumberToken],
+    ['.', Percentage],
+    ['.', Dimension],
+
+    ['+', NumberToken],
+    ['+', Percentage],
+    ['+', Dimension],
+
+    ['/', '*']
+];
+// validate with scripts/generate-safe
+const safePairs = specPairs.concat([
+    [Ident, Hash],
+
+    [Dimension, Hash],
+
+    [Hash, Hash],
+
+    [AtKeyword, LeftParenthesis],
+    [AtKeyword, StringToken],
+    [AtKeyword, Colon],
+
+    [Percentage, Percentage],
+    [Percentage, Dimension],
+    [Percentage, FunctionToken],
+    [Percentage, '-'],
+
+    [RightParenthesis, Ident],
+    [RightParenthesis, FunctionToken],
+    [RightParenthesis, Percentage],
+    [RightParenthesis, Dimension],
+    [RightParenthesis, Hash],
+    [RightParenthesis, '-']
+]);
+
+function createMap(pairs) {
+    const isWhiteSpaceRequired = new Set(
+        pairs.map(([prev, next]) => (code(prev) << 16 | code(next)))
+    );
+
+    return function(prevCode, type, value) {
+        const nextCode = code(type, value);
+        const nextCharCode = value.charCodeAt(0);
+        const emitWs =
+            (nextCharCode === HYPHENMINUS &&
+                type !== Ident &&
+                type !== FunctionToken &&
+                type !== CDC) ||
+            (nextCharCode === PLUSSIGN)
+                ? isWhiteSpaceRequired.has(prevCode << 16 | nextCharCode << 8)
+                : isWhiteSpaceRequired.has(prevCode << 16 | nextCode);
+
+        if (emitWs) {
+            this.emit(' ', WhiteSpace, true);
+        }
+
+        return nextCode;
+    };
+}
+
+export const spec = createMap(specPairs);
+export const safe = createMap(safePairs);