Copyright	(c) 2026
License	MIT
Maintainer	@ocramz
Safe Haskell	None
Language	Haskell2010

Test.Hspec.BenchGolden.CSV

Contents

CSV Generation
File I/O

Description

This module provides CSV export functionality for parameter sweep benchmarks. CSV files are written alongside golden files for convenient analysis and plotting.

CSV Format

The CSV includes columns for:

timestamp - When the benchmark was run (ISO 8601 format)
param_name - The name of the sweep parameter
param_value - The value of the parameter for this row
mean_ms - Mean execution time in milliseconds
stddev_ms - Standard deviation in milliseconds
median_ms - Median execution time in milliseconds
min_ms - Minimum execution time in milliseconds
max_ms - Maximum execution time in milliseconds
trimmed_mean_ms - Trimmed mean (if robust statistics enabled)
mad_ms - Median absolute deviation (if robust statistics enabled)
iqr_ms - Interquartile range (if robust statistics enabled)

Usage

CSV files are automatically generated when using benchGoldenSweep or benchGoldenSweepWith. The file is written to:

<outputDir>/<sweep-name>-<arch-id>.csv

For example: .golden/sort-scaling-aarch64-darwin-Apple_M1.csv

Synopsis

csvHeader :: Text -> Builder
csvRow :: Text -> GoldenStats -> Builder
buildCSV :: Text -> [(Text, GoldenStats)] -> Builder
writeSweepCSV :: FilePath -> Text -> String -> Text -> [(Text, GoldenStats)] -> IO ()
getSweepCSVPath :: FilePath -> Text -> String -> FilePath

CSV Generation

csvHeader :: Text -> Builder Source #

Generate CSV header row.

The header includes all standard statistics columns plus a parameter column.

csvRow :: Text -> GoldenStats -> Builder Source #

Generate a single CSV data row from benchmark stats.

The timestamp is taken from the GoldenStats, and the parameter value is provided separately as a string representation.

buildCSV :: Text -> [(Text, GoldenStats)] -> Builder Source #

Build complete CSV content from a list of (param value, stats) pairs.

Example:

let results = [("1000", stats1), ("5000", stats2), ("10000", stats3)]
let csv = buildCSV "n" results

File I/O

writeSweepCSV :: FilePath -> Text -> String -> Text -> [(Text, GoldenStats)] -> IO () Source #

Write sweep results to a CSV file.

This creates the output directory if it doesn't exist and writes the complete CSV content atomically.

getSweepCSVPath :: FilePath -> Text -> String -> FilePath Source #

Get the path for a sweep CSV file.

The file is placed in the output directory with the architecture ID included in the filename (not as a subdirectory) for easy comparison across architectures.

Example: .golden/sort-scaling-aarch64-darwin-Apple_M1.csv