When you rename a test file the snapshot name changes and the old snapshot is declared obsolete. Thankfully, as Jest snapshots are JS files exporting a bunch of strings, we can compare them with a simple script instead of going through them by hand.

compare-jest-snapshots-between-files.ts

function requireSnapshots(paths: string[]) {
  const map = new Map<string, string>()
  for (const path of paths) {
    const module = require(path)
    for (const name of Object.keys(module)) {
      if (map.has(name)) {
        throw new Error(`Conflict on snapshot "${name}" in ${paths}`)
      }

      map.set(name, module[name])
    }
  }

  return map
}

function findDifferences(
  oldMap: Map<string, string>,
  newMap: Map<string, string>
) {
  const removedSnapshots = Array.from(oldMap.keys()).filter(
    (name) => !newMap.has(name)
  )
  const addedSnapshots = Array.from(newMap.keys()).filter(
    (name) => !oldMap.has(name)
  )

  const commonKeys = new Set([
    ...Array.from(oldMap.keys()),
    ...Array.from(newMap.keys()),
  ])

  const results = Array.from(commonKeys).map((key) => {
    const oldValue = oldMap.get(key)
    const newValue = newMap.get(key)

    if (oldValue !== newValue) {
      return {
        status: 'difference',
        key,
        oldValue,
        newValue,
      }
    } else {
      return {
        status: 'same',
        key,
      }
    }
  })

  return {
    removedSnapshots,
    addedSnapshots,
    results,
  }
}

const newSnapshots = requireSnapshots([
  './Box.spec.tsx.snap',
  './Buttons.spec.tsx.snap',
  './Grid.spec.tsx.snap',
  './index.tsx.snap',
])

const oldSnapshots = requireSnapshots(['./index.js.snap'])

console.log(findDifferences(oldSnapshots, newSnapshots))