diff options
Diffstat (limited to 'lib/gitlab/diff/position_tracer.rb')
| -rw-r--r-- | lib/gitlab/diff/position_tracer.rb | 192 |
1 files changed, 6 insertions, 186 deletions
diff --git a/lib/gitlab/diff/position_tracer.rb b/lib/gitlab/diff/position_tracer.rb index af3df820422..a1c82ce9afc 100644 --- a/lib/gitlab/diff/position_tracer.rb +++ b/lib/gitlab/diff/position_tracer.rb @@ -17,187 +17,13 @@ module Gitlab @paths = paths end - def trace(ab_position) + def trace(old_position) return unless old_diff_refs&.complete? && new_diff_refs&.complete? - return unless ab_position.diff_refs == old_diff_refs + return unless old_position.diff_refs == old_diff_refs - # Suppose we have an MR with source branch `feature` and target branch `master`. - # When the MR was created, the head of `master` was commit A, and the - # head of `feature` was commit B, resulting in the original diff A->B. - # Since creation, `master` was updated to C. - # Now `feature` is being updated to D, and the newly generated MR diff is C->D. - # It is possible that C and D are direct descendants of A and B respectively, - # but this isn't necessarily the case as rebases and merges come into play. - # - # Suppose we have a diff note on the original diff A->B. Now that the MR - # is updated, we need to find out what line in C->D corresponds to the - # line the note was originally created on, so that we can update the diff note's - # records and continue to display it in the right place in the diffs. - # If we cannot find this line in the new diff, this means the diff note is now - # outdated, and we will display that fact to the user. - # - # In the new diff, the file the diff note was originally created on may - # have been renamed, deleted or even created, if the file existed in A and B, - # but was removed in C, and restored in D. - # - # Every diff note stores a Position object that defines a specific location, - # identified by paths and line numbers, within a specific diff, identified - # by start, head and base commit ids. - # - # For diff notes for diff A->B, the position looks like this: - # Position - # start_sha - ID of commit A - # head_sha - ID of commit B - # base_sha - ID of base commit of A and B - # old_path - path as of A (nil if file was newly created) - # new_path - path as of B (nil if file was deleted) - # old_line - line number as of A (nil if file was newly created) - # new_line - line number as of B (nil if file was deleted) - # - # We can easily update `start_sha` and `head_sha` to hold the IDs of - # commits C and D, and can trivially determine `base_sha` based on those, - # but need to find the paths and line numbers as of C and D. - # - # If the file was unchanged or newly created in A->B, the path as of D can be found - # by generating diff B->D ("head to head"), finding the diff file with - # `diff_file.old_path == position.new_path`, and taking `diff_file.new_path`. - # The path as of C can be found by taking diff C->D, finding the diff file - # with that same `new_path` and taking `diff_file.old_path`. - # The line number as of D can be found by using the LineMapper on diff B->D - # and providing the line number as of B. - # The line number as of C can be found by using the LineMapper on diff C->D - # and providing the line number as of D. - # - # If the file was deleted in A->B, the path as of C can be found - # by generating diff A->C ("base to base"), finding the diff file with - # `diff_file.old_path == position.old_path`, and taking `diff_file.new_path`. - # The path as of D can be found by taking diff C->D, finding the diff file - # with `old_path` set to that `diff_file.new_path` and taking `diff_file.new_path`. - # The line number as of C can be found by using the LineMapper on diff A->C - # and providing the line number as of A. - # The line number as of D can be found by using the LineMapper on diff C->D - # and providing the line number as of C. + strategy = old_position.on_text? ? LineStrategy : ImageStrategy - if ab_position.added? - trace_added_line(ab_position) - elsif ab_position.removed? - trace_removed_line(ab_position) - else # unchanged - trace_unchanged_line(ab_position) - end - end - - private - - def trace_added_line(ab_position) - b_path = ab_position.new_path - b_line = ab_position.new_line - - bd_diff = bd_diffs.diff_file_with_old_path(b_path) - - d_path = bd_diff&.new_path || b_path - d_line = LineMapper.new(bd_diff).old_to_new(b_line) - - if d_line - cd_diff = cd_diffs.diff_file_with_new_path(d_path) - - c_path = cd_diff&.old_path || d_path - c_line = LineMapper.new(cd_diff).new_to_old(d_line) - - if c_line - # If the line is still in D but also in C, it has turned from an - # added line into an unchanged one. - new_position = position(cd_diff, c_line, d_line) - if valid_position?(new_position) - # If the line is still in the MR, we don't treat this as outdated. - { position: new_position, outdated: false } - else - # If the line is no longer in the MR, we unfortunately cannot show - # the current state on the CD diff, so we treat it as outdated. - ac_diff = ac_diffs.diff_file_with_new_path(c_path) - - { position: position(ac_diff, nil, c_line), outdated: true } - end - else - # If the line is still in D and not in C, it is still added. - { position: position(cd_diff, nil, d_line), outdated: false } - end - else - # If the line is no longer in D, it has been removed from the MR. - { position: position(bd_diff, b_line, nil), outdated: true } - end - end - - def trace_removed_line(ab_position) - a_path = ab_position.old_path - a_line = ab_position.old_line - - ac_diff = ac_diffs.diff_file_with_old_path(a_path) - - c_path = ac_diff&.new_path || a_path - c_line = LineMapper.new(ac_diff).old_to_new(a_line) - - if c_line - cd_diff = cd_diffs.diff_file_with_old_path(c_path) - - d_path = cd_diff&.new_path || c_path - d_line = LineMapper.new(cd_diff).old_to_new(c_line) - - if d_line - # If the line is still in C but also in D, it has turned from a - # removed line into an unchanged one. - bd_diff = bd_diffs.diff_file_with_new_path(d_path) - - { position: position(bd_diff, nil, d_line), outdated: true } - else - # If the line is still in C and not in D, it is still removed. - { position: position(cd_diff, c_line, nil), outdated: false } - end - else - # If the line is no longer in C, it has been removed outside of the MR. - { position: position(ac_diff, a_line, nil), outdated: true } - end - end - - def trace_unchanged_line(ab_position) - a_path = ab_position.old_path - a_line = ab_position.old_line - b_path = ab_position.new_path - b_line = ab_position.new_line - - ac_diff = ac_diffs.diff_file_with_old_path(a_path) - - c_path = ac_diff&.new_path || a_path - c_line = LineMapper.new(ac_diff).old_to_new(a_line) - - bd_diff = bd_diffs.diff_file_with_old_path(b_path) - - d_line = LineMapper.new(bd_diff).old_to_new(b_line) - - cd_diff = cd_diffs.diff_file_with_old_path(c_path) - - if c_line && d_line - # If the line is still in C and D, it is still unchanged. - new_position = position(cd_diff, c_line, d_line) - if valid_position?(new_position) - # If the line is still in the MR, we don't treat this as outdated. - { position: new_position, outdated: false } - else - # If the line is no longer in the MR, we unfortunately cannot show - # the current state on the CD diff or any change on the BD diff, - # so we treat it as outdated. - { position: nil, outdated: true } - end - elsif d_line # && !c_line - # If the line is still in D but no longer in C, it has turned from - # an unchanged line into an added one. - # We don't treat this as outdated since the line is still in the MR. - { position: position(cd_diff, nil, d_line), outdated: false } - else # !d_line && (c_line || !c_line) - # If the line is no longer in D, it has turned from an unchanged line - # into a removed one. - { position: position(bd_diff, b_line, nil), outdated: true } - end + strategy.new(self).trace(old_position) end def ac_diffs @@ -216,18 +42,12 @@ module Gitlab @cd_diffs ||= compare(new_diff_refs.start_sha, new_diff_refs.head_sha) end + private + def compare(start_sha, head_sha, straight: false) compare = CompareService.new(project, head_sha).execute(project, start_sha, straight: straight) compare.diffs(paths: paths, expanded: true) end - - def position(diff_file, old_line, new_line) - Position.new(diff_file: diff_file, old_line: old_line, new_line: new_line) - end - - def valid_position?(position) - !!position.diff_line(project.repository) - end end end end |