microsoft/typescript-go · error

failed to write trace file header: %w

Error message

failed to write trace file header: %w

What it means

Error "failed to write trace file header: %w" thrown in microsoft/typescript-go.

Source

Thrown at internal/tracing/tracing.go:182

	}
	tr.traceStarted.Store(true)

	// Write the trace file header with metadata events
	tr.traceContent.WriteString("[\n")

	// Write metadata events (matching TypeScript's format)
	metaTs := tr.timestamp()
	tr.metadataTS = metaTs
	tr.writeEvent(traceEvent{PID: 1, TID: mainThreadID, PH: "M", Cat: "__metadata", TS: metaTs, Name: "process_name", Args: map[string]any{"name": "tsgo"}})
	tr.traceContent.WriteString(",\n")
	tr.writeEvent(traceEvent{PID: 1, TID: mainThreadID, PH: "M", Cat: "__metadata", TS: metaTs, Name: "thread_name", Args: map[string]any{"name": "Main"}})
	tr.traceContent.WriteString(",\n")
	tr.writeEvent(traceEvent{PID: 1, TID: mainThreadID, PH: "M", Cat: "disabled-by-default-devtools.timeline", TS: metaTs, Name: "TracingStartedInBrowser"})

	// Truncate any existing trace file with the header so subsequent AppendFile
	// calls extend a clean file.
	if err := tr.fs.WriteFile(tr.tracePath, tr.traceContent.String()); err != nil {
		return nil, fmt.Errorf("failed to write trace file header: %w", err)
	}
	tr.traceContent.Reset()

	return tr, nil
}

// timestamp returns the current timestamp in microseconds.
// In deterministic mode it returns a monotonically increasing counter;
// otherwise it returns the real elapsed wall-clock time since tracing started,
// matching TypeScript's 1000 * timestamp() (microseconds).
func (tr *Tracing) timestamp() float64 {
	if tr.deterministic {
		tr.timestampCounter++
		return float64(tr.timestampCounter)
	}
	return float64(time.Since(tr.startTime).Nanoseconds()) / 1000.0
}

View on GitHub (pinned to 1bcfa18d79)

When it happens

Trigger: Thrown at internal/tracing/tracing.go:182 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of microsoft/typescript-go@1bcfa18d79 (2026-08-16). Data as JSON: /api/errors/3a558356eec2b8f8. Report an issue: GitHub.