overleaf/services/document-updater/app/js/DiffCodec.js
Eric Mc Sween 3217870c04 Merge pull request #17678 from overleaf/em-diff-as-share-js-ops
Make diffAsShareJsOps() synchronous

GitOrigin-RevId: 5a3f96cc2f4b81e27a4ee971667f52c48c07e938
2024-04-03 08:04:09 +00:00

40 lines
906 B
JavaScript

const DMP = require('diff-match-patch')
const dmp = new DMP()
// Do not attempt to produce a diff for more than 100ms
dmp.Diff_Timeout = 0.1
module.exports = {
ADDED: 1,
REMOVED: -1,
UNCHANGED: 0,
diffAsShareJsOp(before, after) {
const diffs = dmp.diff_main(before.join('\n'), after.join('\n'))
dmp.diff_cleanupSemantic(diffs)
const ops = []
let position = 0
for (const diff of diffs) {
const type = diff[0]
const content = diff[1]
if (type === this.ADDED) {
ops.push({
i: content,
p: position,
})
position += content.length
} else if (type === this.REMOVED) {
ops.push({
d: content,
p: position,
})
} else if (type === this.UNCHANGED) {
position += content.length
} else {
throw new Error('Unknown type')
}
}
return ops
},
}