feat: build stats functionality with tests and CLI options

[KARANsinghBISHTT]

Problem

Vite's build command cannot output build statistics in a machine-readable format. Adding build stats feature with tests and CLI options

Expected Behavior

CLI:

• vite build --json - Output JSON to stdout, suppress normal logs
• vite build --json <filename> - Write JSON to file, create parent directories

Output Structure:

{
"version": "...",
"timestamp": ...,
"duration": ...,
"success": true,
"outputs": {
"": {
"outDir": "...",
"chunks": [
{
"name": "...",
"type": "chunk",
"size": ...,
"gzipSize": ...,
"isEntry": ...,
"isDynamicEntry": ...,
"modules": [...],
"imports": [...],
"dynamicImports": [...]
}
],
"assets": [
{
"name": "...",
"type": "asset",
"size": ...,
"gzipSize": ...
}
],
"totals": {
"chunkCount": ...,
"assetCount": ...,
"totalSize": ...,
"totalGzipSize": ...
}
}
},
"warnings": [{ "message": "..." }],
"errors": [{ "message": "..." }]
}

Requirements:

• 2-space indentation
• Exclude *.map files
• Sort chunks/assets by size descending
• gzipSize is null for non-compressible files or when build.reportCompressedSize is false
• totalSize is sum of all chunk and asset sizes
• totalGzipSize is sum of all non-null gzip sizes (null when build.reportCompressedSize is false)
• Output JSON even on build failure with success: false
• outDir must be absolute path

[bluwy]

Can you explain why you need this? Could you write a Vite plugin that extracts some of the information instead? Or use the manifest option?

[graphite-app]

Error handling logic is broken. If writeBuildStats() fails after a successful build, the catch block will create a new stats object with the write error message instead of the build stats, resulting in incorrect JSON output that reports build failure when the build actually succeeded. The try-catch should be restructured to separate build errors from stats writing errors.

try {
  const inlineConfig: InlineConfig = { /* ... */ }
  const builder = await createBuilder(inlineConfig, null)
  await builder.buildApp()

  // Output JSON stats if requested
  if (jsonOutput && builder._buildStats) {
    const { writeBuildStats } = await import('./buildStats')
    try {
      await writeBuildStats(
        builder._buildStats.getStats(true),
        jsonOutput === true ? true : jsonOutput,
      )
    } catch (writeError) {
      // Handle stats writing error separately
      if (!jsonOutput || jsonOutput !== true) {
        createLogger(options.logLevel).error(
          colors.red(`Failed to write stats: ${writeError.message}`),
        )
      }
      process.exit(1)
    }
  }
} catch (e) {
  // Build error handling
  if (jsonOutput) {
    const { BuildStatsCollector, writeBuildStats } = await import('./buildStats')
    const errorCollector = new BuildStatsCollector(false)
    errorCollector.start()
    errorCollector.addError(e.message || 'Build failed')
    await writeBuildStats(
      errorCollector.getStats(false),
      jsonOutput === true ? true : jsonOutput,
    )
  } else {
    createLogger(options.logLevel).error(
      colors.red(`error during build:\n${e.stack}`),
      { error: e },
    )
  }
  process.exit(1)
}

Suggested change

	if (jsonOutput && builder._buildStats) {
	const { writeBuildStats } = await import('./buildStats')
	await writeBuildStats(
	builder._buildStats.getStats(true),
	jsonOutput === true ? true : jsonOutput,
	)
	}
	} catch (e) {
	createLogger(options.logLevel).error(
	colors.red(`error during build:\n${e.stack}`),
	{ error: e },
	)
	// If JSON output is requested, output error as JSON
	if (jsonOutput) {
	const { BuildStatsCollector, writeBuildStats } =
	await import('./buildStats')
	const errorCollector = new BuildStatsCollector(false)
	errorCollector.start()
	errorCollector.addError(e.message || 'Build failed')
	await writeBuildStats(
	errorCollector.getStats(false),
	jsonOutput === true ? true : jsonOutput,
	)
	} else {
	createLogger(options.logLevel).error(
	colors.red(`error during build:\n${e.stack}`),
	{ error: e },
	)
	}
	if (jsonOutput && builder._buildStats) {
	const { writeBuildStats } = await import('./buildStats')
	try {
	await writeBuildStats(
	builder._buildStats.getStats(true),
	jsonOutput === true ? true : jsonOutput,
	)
	} catch (writeError) {
	// Handle stats writing error separately
	createLogger(options.logLevel).error(
	colors.red(`Failed to write stats: ${writeError.message}`),
	)
	process.exit(1)
	}
	}
	} catch (e) {
	// If JSON output is requested, output error as JSON
	if (jsonOutput) {
	const { BuildStatsCollector, writeBuildStats } =
	await import('./buildStats')
	const errorCollector = new BuildStatsCollector(false)
	errorCollector.start()
	errorCollector.addError(e.message || 'Build failed')
	await writeBuildStats(
	errorCollector.getStats(false),
	jsonOutput === true ? true : jsonOutput,
	)
	} else {
	createLogger(options.logLevel).error(
	colors.red(`error during build:\n${e.stack}`),
	{ error: e },
	)
	}
	process.exit(1)

Spotted by Graphite Agent



Is this helpful? React 👍 or 👎 to let us know.