nodegit get diff of all staged files

Question

NodeGit offers an easy way to get a diff of all current changes without the staged changes:

import NodeGit, { Diff } from 'nodegit';

function getUnstagedChanges(path) {
  const repo = await NodeGit.Repository.open(path);
  const diff = await Diff.indexToWorkdir(repo, null, {
    flags: Diff.OPTION.INCLUDE_UNTRACKED |
           Diff.OPTION.RECURSE_UNTRACKED_DIRS
    });
  console.log(await diff.patches());
}

getUnstagedChanges();

Is there a similar solution to get a diff of all staged changes?

Answer 1

Okay I found a way - however it will not work before the first commit was made:

import NodeGit, { Diff } from 'nodegit';

function getStagedChanges(path) {
  const repo = await NodeGit.Repository.open(path);
  const head = await repository.getHeadCommit();
  if (!head) {
    return [];
  }
  const diff = await Diff.treeToIndex(repo, await head.getTree(), null);
  const patches = await diff.patches();
  console.log(patches.map((patch) => patch.newFile().path()));
}

getStagedChanges();

Answer 2

That is strange that you doesn't see staged changes, because indexToWorkdir works exactly like git diff and show only staged changes. I wrote example, that works for me. It show both staged and unstaged files in diff, please try it. If skip options, only staged files showed.

Also take care about replacement of Diff.OPTION.INCLUDE_UNTRACKED to Diff.OPTION.SHOW_UNTRACKED_CONTENT

import path from 'path';
import Git from 'nodegit';

async function print() {
    const repo = await Git.Repository.open(path.resolve(__dirname, '.git'));
    const diff = await Git.Diff.indexToWorkdir(repo, null, {
        flags: Git.Diff.OPTION.SHOW_UNTRACKED_CONTENT | Git.Diff.OPTION.RECURSE_UNTRACKED_DIRS
    });

    // you can't simple log diff here, it logs as empty object
    // console.log(diff); // -> {}

    diff.patches().then((patches) => {
        patches.forEach((patch) => {
            patch.hunks().then((hunks) => {
                hunks.forEach((hunk) => {
                    hunk.lines().then((lines) => {
                        console.log("diff", patch.oldFile().path(), patch.newFile().path());
                        console.log(hunk.header().trim());
                        lines.forEach((line) => {
                            console.log(String.fromCharCode(line.origin()) + line.content().trim());
                        });
                    });
                });
            });
        });
    });

    return diff;
}

print().catch(err => console.error(err));

Answer 3

This way will work even if there's no existing commit, by using the empty tree (the hash for a tree which contains nothing).

import { Repository, Tree, Diff } from 'nodegit';

const emptyTree = '4b825dc642cb6eb9a060e54bf8d69288fbee4904';

function getStagedChanges(path) {
  const repo = await Repository.open(path);

  const head = await repository.getHeadCommit();
  const tree = await (head ? head.getTree() : Tree.lookup(repo, emptyTree));

  const diff = await Diff.treeToIndex(repo, await head.getTree(), null);
  const patches = await diff.patches();
  console.log(patches.map((patch) => patch.newFile().path()));
}

getStagedChanges('/path/to/repo');