npm error trying to install git repository

Having followed another SO, I am trying to include the latest version of a git repo (LeafletJS) that has yet to be pushed to npm.

The packages.config snipped:

"dependencies": {
 "leaflet": "git+https://{git hub generated token}:x-oauth-basic@github.com/Leaflet/Leaflet.git",

then,

npm install

reports

npm WARN addRemoteGit Error: Command failed: git -c core.longpaths=true config --get remote.origin.url

npm WARN addRemoteGit

npm WARN addRemoteGit at ChildProcess.exithandler (child_process.js:206:12)

npm WARN addRemoteGit at emitTwo (events.js:106:13)

npm WARN addRemoteGit at ChildProcess.emit (events.js:191:7)

npm WARN addRemoteGit at maybeClose (internal/child_process.js:877:16)

npm WARN addRemoteGit at Process.ChildProcess._handle.onexit (internal/child_process.js:226:5)

npm WARN addRemoteGit git+https://{token}:x-oauth-basic@github.com/Leaflet/Leaflet.git resetting remote C:\Users\bob\AppData\Roaming\npm-cache_git-remotes\git-https-{token}-x-oauth-basic- github-com-Leaflet-Leaflet-git-b27a5a7d because of error: { Error: Command failed: git -c core.longpaths=true config --get remote.origin.url

npm WARN addRemoteGit

npm WARN addRemoteGit at ChildProcess.exithandler (child_process.js:206:12)

npm WARN addRemoteGit at emitTwo (events.js:106:13)

npm WARN addRemoteGit at ChildProcess.emit (events.js:191:7)

npm WARN addRemoteGit at maybeClose (internal/child_process.js:877:16)

npm WARN addRemoteGit at Process.ChildProcess._handle.onexit (internal/child_process.js:226:5)

npm WARN addRemoteGit killed: false,

npm WARN addRemoteGit code: 1,

npm WARN addRemoteGit signal: null,

npm WARN addRemoteGit cmd: 'git -c core.longpaths=true config --get remote.origin.url' }

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