fix: diff-sequences export not playing nice with Vite

package.json

@@ -23,7 +23,7 @@
     "lint": "prettier --check --plugin-search-dir=. .",
     "__lint": "prettier --check --plugin-search-dir=. . && eslint --cache --ignore-path .gitignore .",
     "format": "prettier --write --plugin-search-dir=. .",
-    "prepare": "husky install && cd tools && node generateEmbeddedAceJsonWorker.js && cd ..",
+    "prepare": "husky install && cd tools && node generateEmbeddedAceJsonWorker.js && node generateDiffSequenceEsm.js && cd ..",
     "release": "npm run lint && npm test && standard-version && npm run package && git push && git push --tag && npm publish package/"
   },
   "dependencies": {

src/lib/logic/sort.js

@@ -1,11 +1,9 @@
-import diffSequencesExport from 'diff-sequences'
+import diffSequence from '../generated/diffSequence.js'
 import { compileJSONPointer, getIn, setIn } from 'immutable-json-patch'
 import { first, initial, isEmpty, isEqual, last } from 'lodash-es'
 import naturalCompare from 'natural-compare-lite'
 import { parseJSONPointerWithArrayIndices } from '../utils/jsonPointer.js'
 
-const diffSequences = diffSequencesExport.default || diffSequencesExport
-
 export function caseInsensitiveNaturalCompare(a, b) {
   const aLower = typeof a === 'string' ? a.toLowerCase() : a
   const bLower = typeof b === 'string' ? b.toLowerCase() : b
@@ -166,7 +164,7 @@ export function sortOperationsMoveAdvanced(array, comparator) {
     return aIndex === sortedIndices[bIndex]
   }
 
-  diffSequences(size, size, isCommon, foundSubsequence)
+  diffSequence(size, size, isCommon, foundSubsequence)
   foundSubsequence(0, size, size)
 
   // every move will change the actual indices, so we've to adjust for that

tools/generateDiffSequenceEsm.js

@@ -0,0 +1,30 @@
+import { readFileSync, writeFileSync } from 'fs'
+
+// The original file contains an export that doesn't play nice with Vite
+// This script copies the source code and turns it into regular a ES module
+// The original export looks like:
+//
+//     Object.defineProperty(exports, '__esModule', {
+//       value: true
+//     });
+//     exports.default = diffSequence;
+//
+// The ESM export looks like:
+//
+//     export default diffSequence;
+
+const commonjsFile = '../node_modules/diff-sequences/build/index.js'
+const esmFile = '../src/lib/generated/diffSequence.js'
+const commonjsCode = String(readFileSync(commonjsFile))
+
+const commentsStart = commonjsCode.indexOf('/**')
+
+const esmHeader = `// esm version of diff-sequences
+// generated by ./tools/generateDiffSequenceEsm.js
+export default diffSequence;
+
+`
+
+const esmCode = esmHeader + commonjsCode.slice(commentsStart)
+
+writeFileSync(esmFile, esmCode)