gitlab-org--gitlab-foss/lib/gitlab/diff/diff_refs.rb
2017-09-25 10:23:43 +02:00

68 lines
2.2 KiB
Ruby

module Gitlab
module Diff
class DiffRefs
attr_reader :base_sha
attr_reader :start_sha
attr_reader :head_sha
def initialize(base_sha:, start_sha: base_sha, head_sha:)
@base_sha = base_sha
@start_sha = start_sha
@head_sha = head_sha
end
def ==(other)
other.is_a?(self.class) &&
shas_equal?(base_sha, other.base_sha) &&
shas_equal?(start_sha, other.start_sha) &&
shas_equal?(head_sha, other.head_sha)
end
alias_method :eql?, :==
def hash
[base_sha, start_sha, head_sha].hash
end
# There is only one case in which we will have `start_sha` and `head_sha`,
# but not `base_sha`, which is when a diff is generated between an
# orphaned branch and another branch, which means there _is_ no base, but
# we're still able to highlight it, and to create diff notes, which are
# the primary things `DiffRefs` are used for.
# `DiffRefs` are "complete" when they have `start_sha` and `head_sha`,
# because `base_sha` can always be derived from this, to return an actual
# sha, or `nil`.
# We have `base_sha` directly available on `DiffRefs` because it's faster#
# than having to look it up in the repo every time.
def complete?
start_sha && head_sha
end
def compare_in(project)
# We're at the initial commit, so just get that as we can't compare to anything.
if Gitlab::Git.blank_ref?(start_sha)
project.commit(head_sha)
else
straight = start_sha == base_sha
CompareService.new(project, head_sha).execute(project, start_sha, straight: straight)
end
end
private
def shas_equal?(sha1, sha2)
return true if sha1 == sha2
return false if sha1.nil? || sha2.nil?
return false unless sha1.class == sha2.class
length = [sha1.length, sha2.length].min
# If either of the shas is below the minimum length, we cannot be sure
# that they actually refer to the same commit because of hash collision.
return false if length < Commit::MIN_SHA_LENGTH
sha1[0, length] == sha2[0, length]
end
end
end
end