stacked-pr-sync/src/services/conflict-detector.js

A Node.js tool for syncing stacked pull requests with advanced conflict detection and resolution

const { performDryRunMerge } = require('../utils/git')
const { logStep, logSuccess, logError, logWarning, logInfo } = require('../utils/logger')

// Check all potential merge conflicts before starting sync
async function checkAllPotentialConflicts(branches) {
  logStep('Conflict Check', 'Checking for potential merge conflicts across all branches...')

  const conflicts = []

  for (let i = 0; i < branches.length - 1; i++) {
    const sourceBranch = branches[i]
    const targetBranch = branches[i + 1]

    logInfo(`Checking: ${sourceBranch} → ${targetBranch}`)
    const result = performDryRunMerge(sourceBranch, targetBranch)

    if (result.hasConflicts) {
      conflicts.push({
        sourceBranch,
        targetBranch,
        error: result.error,
      })
      logError(`⚠ Potential conflicts detected: ${sourceBranch} → ${targetBranch}`)
    } else {
      logSuccess(`✓ No conflicts: ${sourceBranch} → ${targetBranch}`)
    }
  }

  return conflicts
}

// Handle detected conflicts before starting sync
async function handlePreDetectedConflicts(conflicts) {
  if (conflicts.length === 0) {
    logSuccess('No potential conflicts detected! Safe to proceed with sync.')
    return true
  }

  logError(`\n⚠️  ${conflicts.length} potential merge conflict(s) detected:`)
  conflicts.forEach((conflict, index) => {
    logError(`  ${index + 1}. ${conflict.sourceBranch} → ${conflict.targetBranch}`)
  })

  logWarning('\nPlease resolve these conflicts before proceeding with the sync.')
  logInfo('Resolve conflicts in the following order:')

  conflicts.forEach((conflict, index) => {
    logInfo(`  ${index + 1}. Switch to ${conflict.targetBranch} and merge ${conflict.sourceBranch}`)
    logInfo(`     git checkout ${conflict.targetBranch}`)
    logInfo(`     git merge ${conflict.sourceBranch}`)
    logInfo(`     # Resolve conflicts, then: git add . && git commit`)
  })

  logInfo('\nAfter resolving conflicts, run the sync command again.')
  process.exit(1)
}

module.exports = {
  checkAllPotentialConflicts,
  handlePreDetectedConflicts,
}