Remove payload definitions from V3 git/types.js (#402)

Test Plan:
Existing Flow and unit tests suffice.

wchargin-branch: git-v3-remove-payloads

src/v3/plugins/git/types.js

@@ -1,10 +1,5 @@
 // @flow
 
-import stringify from "json-stable-stringify";
-
-export const GIT_PLUGIN_NAME = "sourcecred/git-beta";
-
-// Logical types
 export type Repository = {|
   +commits: {[Hash]: Commit},
   +trees: {[Hash]: Tree},
@@ -25,127 +20,3 @@ export type TreeEntry = {|
   +name: string,
   +hash: Hash,
 |};
-
-// Graph types
-
-// Nodes
-export const COMMIT_NODE_TYPE: "COMMIT" = "COMMIT";
-export type CommitNodePayload = {||};
-
-export const TREE_NODE_TYPE: "TREE" = "TREE";
-export type TreeNodePayload = {||};
-
-export const BLOB_NODE_TYPE: "BLOB" = "BLOB";
-export type BlobNodePayload = {||}; // we do not store the content
-
-// In Git, a tree may point to a commit directly; in our graph, we have
-// an explicit notion of "submodule commit", because, a priori, we do
-// not know the repository to which the commit belongs. A submodule
-// commit node stores the hash of the referent commit, as well as the
-// URL to the subproject as listed in the .gitmodules file.
-export const SUBMODULE_COMMIT_NODE_TYPE: "SUBMODULE_COMMIT" =
-  "SUBMODULE_COMMIT";
-export function submoduleCommitId(hash: Hash, submoduleUrl: string) {
-  return `${submoduleUrl}@${hash}`;
-}
-export type SubmoduleCommitPayload = {|
-  +hash: Hash,
-  +url: string, // from .gitmodules file
-|};
-
-export const TREE_ENTRY_NODE_TYPE: "TREE_ENTRY" = "TREE_ENTRY";
-export type TreeEntryNodePayload = {|
-  +name: string,
-|};
-export function treeEntryId(tree: Hash, name: string): string {
-  return `${tree}:${name}`;
-}
-
-export type NodePayload =
-  | BlobNodePayload
-  | CommitNodePayload
-  | SubmoduleCommitPayload
-  | TreeEntryNodePayload
-  | TreeNodePayload;
-
-export type NodeType =
-  | typeof BLOB_NODE_TYPE
-  | typeof COMMIT_NODE_TYPE
-  | typeof SUBMODULE_COMMIT_NODE_TYPE
-  | typeof TREE_ENTRY_NODE_TYPE
-  | typeof TREE_NODE_TYPE;
-
-// Edges
-
-// CommitNode -> CommitNode
-export const HAS_PARENT_EDGE_TYPE: "HAS_PARENT" = "HAS_PARENT";
-export type HasParentEdgePayload = {|
-  +parentIndex: number, // one-based
-|};
-export function hasParentEdgeId(
-  childCommitHash: Hash,
-  oneBasedParentIndex: number
-) {
-  if (
-    !isFinite(oneBasedParentIndex) ||
-    oneBasedParentIndex !== Math.floor(oneBasedParentIndex) ||
-    oneBasedParentIndex < 1
-  ) {
-    throw new Error(
-      "Expected positive integer parent index, " +
-        `but got: ${String(oneBasedParentIndex)}`
-    );
-  }
-  return `${childCommitHash}^${String(oneBasedParentIndex)}`;
-}
-
-// CommitNode -> TreeNode
-export const HAS_TREE_EDGE_TYPE: "HAS_TREE" = "HAS_TREE";
-export type HasTreeEdgePayload = {||};
-
-// TreeNode -> TreeEntryNode
-export const INCLUDES_EDGE_TYPE: "INCLUDES" = "INCLUDES";
-export type IncludesEdgePayload = {|
-  +name: string,
-|};
-export function includesEdgeId(treeSha: string, name: string): string {
-  return `${treeSha}:${name}`;
-}
-
-// TreeEntryNode -> TreeEntryNode
-// TODO: Rename the BECOMES edges to EVOLVES, as then we can cleanly express
-// the bidrectional relationship: EvolvesTo and EvolvesFrom.  Note that doing
-// so is a breaking change, and thus this change should be made after we have a
-// versioning system that can either maintain backcompat or invalidate old
-// serializations. See #280
-export const BECOMES_EDGE_TYPE: "BECOMES" = "BECOMES";
-export type BecomesEdgePayload = {|
-  +childCommit: Hash,
-  +parentCommit: Hash,
-  +path: $ReadOnlyArray<string>,
-|};
-export function becomesEdgeId(
-  childCommit: Hash,
-  parentCommit: Hash,
-  path: $ReadOnlyArray<string>
-) {
-  return stringify({childCommit, parentCommit, path});
-}
-
-// TreeEntryNode -> BlobNode | TreeNode
-export const HAS_CONTENTS_EDGE_TYPE: "HAS_CONTENTS" = "HAS_CONTENTS";
-export type HasContentsEdgePayload = {||};
-
-export type EdgeType =
-  | typeof HAS_TREE_EDGE_TYPE
-  | typeof HAS_PARENT_EDGE_TYPE
-  | typeof INCLUDES_EDGE_TYPE
-  | typeof BECOMES_EDGE_TYPE
-  | typeof HAS_CONTENTS_EDGE_TYPE;
-
-export type EdgePayload =
-  | HasTreeEdgePayload
-  | HasParentEdgePayload
-  | IncludesEdgePayload
-  | BecomesEdgePayload
-  | HasContentsEdgePayload;