Cannot view diff for commits on a new branch

[bradleyfalzon]

GitHub push event for a push to a new branch set Created to true and GopherCI incorrectly detects this as a first commit it a new repository:

gopherci/internal/github/handlers.go

Lines 238 to 246 in af52b55

	// PushConfig returns an AnalyseConfig for a GitHub Push Event.
	func PushConfig(e *github.PushEvent) AnalyseConfig {
	// commitFrom is after~numCommits for the same reason as baseRef but
	// also because first pushes's before is 000000.... which can't be
	// used in api request
	commitFrom := fmt.Sprintf("%v~%v", *e.After, len(e.Commits))
	if e.Created != nil && *e.Created {
	commitFrom = ""
	}

So when a push to a new branch occurs, we blank the commitFrom as a way of telling other API calls, that there was no previous diff. This is true for a new repository, but not for a new branch on an existing repository (with a shared tree?). The push event still has a compare URL using ^ to indicate a comparison between the first commit's parent and the latest commit.

Example push to a new branch dev (Delivery ID: 9bf33710-8164-11e7-864b-47facb9a6108):

{
  "ref": "refs/heads/dev",
  "before": "0000000000000000000000000000000000000000",
  "after": "f67",
  "created": true,
  "deleted": false,
  "forced": false,
  "base_ref": null,
  "compare": "https://github.com/owner/repo/compare/d5ed^...f67",
  "commits": [
    {
      "id": "d5ed",
      "tree_id": "91b5c",
      "distinct": true,
      "message": "",
      "timestamp": "",
      "url": "https://github.com/owner/repo/commit/d5ed",
      "author": {

      },
      "committer": {

      },
      "added": [

      ],
      "removed": [

      ],
      "modified": [
        "main.go"
      ]
    },
    {
      "id": "36a1",
      "tree_id": "2f10",
      "distinct": true,
      "message": "",
      "timestamp": "",
      "url": "https://github.com/owner/repo/commit/36a",
      "author": {

      },
      "committer": {

      },
      "added": [

      ],
      "removed": [

      ],
      "modified": [
        "main.go"
      ]
    },
    {
      "id": "f67",
      "tree_id": "f22",
      "distinct": true,
      "message": "",
      "timestamp": "",
      "url": "https://github.com/owner/repo/commit/f67",
      "author": {

      },
      "committer": {

      },
      "added": [

      ],
      "removed": [

      ],
      "modified": [
        "main.go"
      ]
    }
  ],
  "head_commit": {
    "id": "f67",
    "tree_id": "f22",
    "distinct": true,
    "message": "",
    "timestamp": "",
    "url": "https://github.com/owner/repo/commit/f67",
    "author": {

    },
    "committer": {

    },
    "added": [

    ],
    "removed": [

    ],
    "modified": [
      "main.go"
    ]
  },
  "repository": {
  },
  "pusher": {

  },
  "sender": {

  },
  "installation": {
    "id":
  }
}

Example push to a new repository (Delivery ID: ff8bc440-80e7-11e7-8913-69c56684fd07):

{
  "ref": "refs/heads/master",
  "before": "0000000000000000000000000000000000000000",
  "after": "5263ba3517f5b1ed8dee3c721ac7217fcba66cb2",
  "created": true,
  "deleted": false,
  "forced": false,
  "base_ref": null,
  "compare": "https://github.com/bradleyfalzon/dep-case-collision/commit/5263ba3517f5",
  "commits": [
    {
      "id": "5263ba3517f5b1ed8dee3c721ac7217fcba66cb2",
      "tree_id": "a0b3e38811d80665fc0b7884cc47cb4b06a14c8e",
      "distinct": true,
      "message": "Initial commit",
      "timestamp": "2017-08-14T21:28:26+09:30",
      "url": "https://github.com/bradleyfalzon/dep-case-collision/commit/5263ba3517f5b1ed8dee3c721ac7217fcba66cb2",
      "author": {

      },
      "committer": {

      },
      "added": [
        "README.md",
        "foo.go"
      ],
      "removed": [

      ],
      "modified": [

      ]
    }
  ],
  "head_commit": {
    "id": "5263ba3517f5b1ed8dee3c721ac7217fcba66cb2",
    "tree_id": "a0b3e38811d80665fc0b7884cc47cb4b06a14c8e",
    "distinct": true,
    "message": "Initial commit",
    "timestamp": "2017-08-14T21:28:26+09:30",
    "url": "https://github.com/bradleyfalzon/dep-case-collision/commit/5263ba3517f5b1ed8dee3c721ac7217fcba66cb2",
    "author": {

    },
    "committer": {

    },
    "added": [
      "README.md",
      "foo.go"
    ],
    "removed": [

    ],
    "modified": [

    ]
  },
  "repository": {

  },
  "pusher": {

  },
  "sender": {

  },
  "installation": {
    "id":
  }
}

About the only thing that looks like something I can use is to check if the compare URL contains ^....... 🤔