imterah/element-portable
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

unit test + fixes + comments + simplication for diffDeletion

Browse source
This commit is contained in:
Bruno Windels 2019-07-18 18:09:31 +02:00
parent cef67d5784
commit 595dc82543
2 changed files with 51 additions and 21 deletions
Download patch file Download diff file Expand all files Collapse all files

24
src/editor/diff.js
View file

@ -25,16 +25,6 @@ function firstDiff(a, b) {
return compareLen;
}
function lastDiff(a, b) {
const compareLen = Math.min(a.length, b.length);
for (let i = 0; i < compareLen; ++i) {
if (a[a.length - i] !== b[b.length - i]) {
return i;
}
}
return compareLen;
}
function diffStringsAtEnd(oldStr, newStr) {
const len = Math.min(oldStr.length, newStr.length);
const startInCommon = oldStr.substr(0, len) === newStr.substr(0, len);
@ -52,22 +42,14 @@ function diffStringsAtEnd(oldStr, newStr) {
}
}
// assumes only characters have been deleted at one location in the string, and none added
export function diffDeletion(oldStr, newStr) {
if (oldStr === newStr) {
return {};
}
const firstDiffIdx = firstDiff(oldStr, newStr);
const lastDiffIdx = oldStr.length - lastDiff(oldStr, newStr) + 1;
return {at: firstDiffIdx, removed: oldStr.substring(firstDiffIdx, lastDiffIdx)};
}
export function diffInsertion(oldStr, newStr) {
const diff = diffDeletion(newStr, oldStr);
if (diff.removed) {
return {at: diff.at, added: diff.removed};
} else {
return diff;
}
const amount = oldStr.length - newStr.length;
return {at: firstDiffIdx, removed: oldStr.substr(firstDiffIdx, amount)};
}
export function diffAtCaret(oldValue, newValue, caretPosition) {