@humanspeak/svelte-markdown/dist/utils/stream-benchmark.js

Markdown and HTML renderer for Svelte 5 — built for rendering streaming AI agent output from Claude Code, ChatGPT, and agentic workflows. XSS-safe defaults, streaming-aware sanitization, token caching, TypeScript types, and Svelte 5 runes.

import { IncrementalParser } from './incremental-parser.js';
/**
 * Calculates the p-th percentile of a numeric array.
 *
 * @param values - Array of numeric values
 * @param p - Percentile to calculate (0-1, e.g., 0.95 for 95th percentile)
 * @returns The value at the specified percentile, or 0 if array is empty
 */
const percentile = (values, p) => {
    if (values.length === 0)
        return 0;
    const sorted = [...values].sort((a, b) => a - b);
    const index = Math.min(sorted.length - 1, Math.max(0, Math.ceil(sorted.length * p) - 1));
    return sorted[index];
};
/**
 * Benchmarks incremental parsing performance by simulating streaming chunk appends.
 *
 * @param chunks - Array of string chunks to append sequentially
 * @param options - SvelteMarkdown parser options forwarded to IncrementalParser
 * @returns Benchmark results including per-chunk timing, peak, and p95 parse durations
 *
 * @example
 * ```ts
 * const chunks = ['# Hello ', 'world, ', 'this is a test.']
 * const result = benchmarkAppendStream(chunks, { gfm: true })
 * console.log(result.p95ParseMs, result.peakParseMs)
 * ```
 */
export const benchmarkAppendStream = (chunks, options) => {
    const parser = new IncrementalParser(options);
    const parseDurationsMs = [];
    let source = '';
    let finalTokens = [];
    for (const chunk of chunks) {
        source += chunk;
        const start = performance.now();
        const result = parser.update(source);
        const elapsed = performance.now() - start;
        parseDurationsMs.push(elapsed);
        finalTokens = result.tokens;
    }
    const totalParseMs = parseDurationsMs.reduce((sum, duration) => sum + duration, 0);
    return {
        totalChars: source.length,
        chunkCount: chunks.length,
        totalParseMs,
        peakParseMs: parseDurationsMs.length > 0 ? Math.max(...parseDurationsMs) : 0,
        p95ParseMs: percentile(parseDurationsMs, 0.95),
        finalTokens,
        parseDurationsMs
    };
};