compose-highlight/dev.hossain.highlight.engine/HighlightTimings

HighlightTimings

data class HighlightTimings(val jsBridge: Duration, val jsonUnescape: Duration, val htmlParse: Duration, val themeParse: Duration, val total: Duration)

Per-layer timing breakdown for a single highlight call.

Each field is a Duration measured via measureTimedValue at each pipeline stage. All fields are always populated - themeParse is non-zero only on the first call for a given HighlightTheme (the CSS parse is lazy and cached; subsequent calls report Duration.ZERO).

Pipeline stages

Stage	Description
jsBridge	`evaluateJavascript()` round-trip into WebView running highlight.js
jsonUnescape	`unescapeJsString()` pass over the returned JSON string
htmlParse	HTML parsing into a node tree and building the AnnotatedString
themeParse	Theme CSS parsing - first-use only; Duration.ZERO on cache hits
total	End-to-end time for the full highlight call

Usage

engine.highlight(code, "kotlin", theme).onSuccess { result ->
    val t = result.timings
    println("JS bridge:    ${t.jsBridge}")        // e.g. "45ms"
    println("JSON unescape:${t.jsonUnescape}")     // e.g. "1ms"
    println("HTML parse:   ${t.htmlParse}")        // e.g. "3ms"
    println("Theme parse:  ${t.themeParse}")       // non-zero on first call only
    println("Total:        ${t.total}")            // full elapsed wall-clock time
    // Or get raw numbers:
    val jsBridgeMs = t.jsBridge.inWholeMilliseconds
    val htmlParseNs = t.htmlParse.inWholeNanoseconds
}

Constructors

HighlightTimings

constructor(jsBridge: Duration, jsonUnescape: Duration, htmlParse: Duration, themeParse: Duration, total: Duration)

Properties

htmlParse

val htmlParse: Duration

Time for parsing the highlight.js HTML output and building the androidx.compose.ui.text.AnnotatedString in a single SAX-style pass.

jsBridge

val jsBridge: Duration

Time for the evaluateJavascript() round-trip - from immediately before the call to when the JS result callback fires. Excludes WebView warm-up and mutex-wait time.

jsonUnescape

val jsonUnescape: Duration

Time for unescapeJsString - the character-by-character pass that strips JSON encoding from the string returned by the JS engine.

themeParse

val themeParse: Duration

Time for theme CSS parsing on first use of a HighlightTheme. Duration.ZERO on all subsequent calls for the same theme instance because the color map is lazily computed and cached.

total

val total: Duration

Full elapsed wall-clock time for the HighlightEngine.highlight call. Measured end-to-end and includes overhead not captured by the individual stage fields (WebView initialization wait, mutex queuing, dispatcher hops). Use this for overall latency; use the individual stage fields to identify which layer is the bottleneck. Equals HighlightResult.durationMs converted to Duration.