refactor: circular deps part 14

packages/core/css-value/reworkcss-value.ts

@@ -0,0 +1,131 @@
+export interface CSSValue {
+	type: string;
+	string: string;
+	unit?: string;
+	value?: number;
+}
+
+export interface CommaToken {
+	type: 'comma';
+	string: ',';
+}
+
+export interface IdentToken {
+	type: 'ident';
+	string: string;
+}
+
+export interface NumberToken {
+	type: 'number';
+	string: string;
+	unit: string;
+	value: number;
+}
+
+export interface StringToken {
+	type: 'string';
+	quote: '"' | "'";
+	string: string;
+	value: string;
+}
+
+export type Token = CommaToken | IdentToken | NumberToken | StringToken;
+
+/**
+ * Parse a string into an array of tokens.
+ */
+export function parse(str: string): Token[] {
+	return new Parser(str).parse();
+}
+
+class Parser {
+	private str: string;
+
+	constructor(str: string) {
+		this.str = str;
+	}
+
+	private skip(match: RegExpExecArray): void {
+		this.str = this.str.slice(match[0].length);
+	}
+
+	/** Comma tokens: "," */
+	private comma(): CommaToken | undefined {
+		const m = /^, */.exec(this.str);
+		if (!m) return;
+		this.skip(m);
+		return { type: 'comma', string: ',' };
+	}
+
+	/** Identifier tokens: word or dash sequences */
+	private ident(): IdentToken | undefined {
+		const m = /^([\w-]+) */.exec(this.str);
+		if (!m) return;
+		this.skip(m);
+		return { type: 'ident', string: m[1] };
+	}
+
+	/** Integer tokens, possibly with unit */
+	private int(): NumberToken | undefined {
+		const m = /^(([-+]?\d+)(\S+)?) */.exec(this.str);
+		if (!m) return;
+		this.skip(m);
+		const n = parseInt(m[2], 10);
+		const u = m[3] || '';
+		return { type: 'number', string: m[1], unit: u, value: n };
+	}
+
+	/** Float tokens, possibly with unit */
+	private float(): NumberToken | undefined {
+		const m = /^(((?:[-+]?\d+)?\.\d+)(\S+)?) */.exec(this.str);
+		if (!m) return;
+		this.skip(m);
+		const n = parseFloat(m[2]);
+		const u = m[3] || '';
+		return { type: 'number', string: m[1], unit: u, value: n };
+	}
+
+	/** Number tokens, either float or int */
+	private number(): NumberToken | undefined {
+		return this.float() || this.int();
+	}
+
+	/** Double-quoted strings */
+	private double(): StringToken | undefined {
+		const m = /^"([^"]*)" */.exec(this.str);
+		if (!m) return;
+		this.skip(m);
+		return { type: 'string', quote: '"', string: `"${m[1]}"`, value: m[1] };
+	}
+
+	/** Single-quoted strings */
+	private single(): StringToken | undefined {
+		const m = /^'([^']*)' */.exec(this.str);
+		if (!m) return;
+		this.skip(m);
+		return { type: 'string', quote: "'", string: `'${m[1]}'`, value: m[1] };
+	}
+
+	/** String tokens: single or double quoted */
+	private string(): StringToken | undefined {
+		return this.single() || this.double();
+	}
+
+	/** Attempt to parse any token */
+	private value(): Token | undefined {
+		return this.number() || this.ident() || this.string() || this.comma();
+	}
+
+	/** Run the full parse loop */
+	public parse(): Token[] {
+		const vals: Token[] = [];
+		while (this.str.length > 0) {
+			const obj = this.value();
+			if (!obj) {
+				throw new Error(`failed to parse near \`${this.str.slice(0, 10)}...\``);
+			}
+			vals.push(obj);
+		}
+		return vals;
+	}
+}