chore: Add in-repo reviewable config.

.github/workflows/ci.yml

@@ -1,8 +1,6 @@
 name: ci
 
 on:
-  push:
-    branches: [master]
   pull_request:
     branches: [master]
 

.reviewable/completion.js

@@ -0,0 +1,58 @@
+// jshint esversion: 6
+
+// This code will check that the pull request has been approved via GitHub review approval by a
+// minimum number of reviewers and by all assignees, and that no changes were requested by any
+// reviewers.  Only reviewers with write access to the repository are considered.
+//
+// This is very similar to GitHub's built-in branch protection option to require pull request
+// reviews before merging, but allows for much more flexibility and customization.
+
+// dependencies: lodash4
+
+// The number of approvals required to merge.
+let numApprovalsRequired = 1;
+
+const approvals = review.pullRequest.approvals;
+
+let numApprovals = _.filter(approvals, (x) => x === 'approved').length;
+const numRejections = _.filter(approvals, (x) => x === 'changes_requested').length;
+
+const discussionBlockers = _(review.discussions)
+  .filter((x) => !x.resolved)
+  .flatMap('participants')
+  .filter((x) => !x.resolved)
+  .map(user => _.pick(user, 'username'))
+  .value();
+
+let pendingReviewers = _(discussionBlockers)
+  .map(user => _.pick(user, 'username'))
+  .concat(review.pullRequest.requestedReviewers)
+  .value();
+
+const required = _.map(review.pullRequest.assignees, 'username');
+_.pull(required, review.pullRequest.author.username);
+if (required.length) {
+  numApprovalsRequired = _.max([required.length, numApprovalsRequired]);
+  numApprovals =
+    (_(approvals).pick(required).filter('approved').size()) +
+    _.min([numApprovals, numApprovalsRequired - required.length]);
+  pendingReviewers = _(required)
+    .reject(username => approvals[username] === 'approved')
+    .reject(username => pendingReviewers.length && approvals[username])
+    .map(username => ({username}))
+    .concat(pendingReviewers)
+    .value();
+}
+
+pendingReviewers = _.uniqBy(pendingReviewers, 'username');
+
+const description =
+  (numRejections ? `${numRejections} change requests, ` : '') +
+  `${numApprovals} of ${numApprovalsRequired} approvals obtained`;
+const shortDescription =
+  (numRejections ? `${numRejections} ✗, ` : '') + `${numApprovals} of ${numApprovalsRequired} ✓`;
+
+return {
+  completed: numApprovals >= numApprovalsRequired,
+  description, shortDescription, pendingReviewers
+};

.reviewable/settings.yaml

@@ -0,0 +1,4 @@
+# Reviewable settings file. Read the docs at https://docs.reviewable.io/repositories.html#store-repository-settings-using-the-reviewable-directory
+approval-text: ":lgtm_strong:"
+github-status:
+  updates: always