prow/config/branch_protection.go
func (c *Config) GetBranchProtection(org, repo, branch string) (*Policy, error) {
	if _, present := c.BranchProtection.Orgs[org]; !present {
		return nil, nil // only consider branches in configured orgs
	}
	b, err := c.BranchProtection.GetOrg(org).GetRepo(repo).GetBranch(branch)
	if err != nil {
		return nil, err
	}

	return c.GetPolicy(org, repo, branch, *b)
}
func (c *Config) GetBranchProtection(org, repo, branch string) (*Policy, error) {
	if _, present := c.BranchProtection.Orgs[org]; !present {
		return nil, nil // only consider branches in configured orgs
	}
	b, err := c.BranchProtection.GetOrg(org).GetRepo(repo).GetBranch(branch)
	if err != nil {
		return nil, err
	}

	return c.GetPolicy(org, repo, branch, *b)
}
// GetBranchProtection returns the policy for a given branch.
//
// Handles merging any policies defined at repo/org/global levels into the branch policy.