A workaround to get diffs between commits, related to: https://github.com/MicrosoftDocs/vsts-rest-api-specs/issues/20

vsts_fetch_diffs_workaround.js

/*
The url and approach was reverse engineered from the deploy view of VSTS
The important part here is the `start_commit`-id and the `stop_commit`-id.
*/
const postBody = {
  context: {
    properties: {
      repositoryName: <repository>,
      projectName: <project_name>,
      searchCriteria: {
        gitCommitLookupArguments: null,
        gitHistoryQueryArguments: {
          startFromVersion: {
            versionOptions: 0,
            versionType: 2,
            version: <start_commit>
          },
          notInVersion: { versionOptions: 0, versionType: 2, version: <stop_commit> },
          order: 0,
          path: '',
          historyMode: 0,
          stopAtAdds: false,
          author: null,
          committer: null
        },
        gitArtifactsQueryArguments: null,
        gitGraphQueryArguments: {
          fetchGraph: false,
          emptyLineLengthLimit: 20,
          emptyLineLengthMultiplier: false,
          order: 0
        }
      }
    }
  },
  contributionIds: ['ms.vss-code-web.git-history-view-commits-data-provider']
};

fetch({
  uri: 'https://<account>.visualstudio.com/_apis/Contribution/dataProviders/query/project/<project>?api-version=5.0-preview.1',
  method: 'POST',
  body: postBody,
  json: true
}).auth(<username>, <personal_access_token>)

How did you come up with such a solution?!!!
BTW, which pkg are "fetch" and "auth" in?
Which API is applied?