Add latest changes from gitlab-org/gitlab@13-10-stable-eev13.10.0-rc40

7 files changed, 84 insertions, 112 deletions

diff --git a/lib/gitlab/diff/char_diff.rb b/lib/gitlab/diff/char_diff.rb
index c8bb39e9f5d..1b3af8f75ca 100644
--- a/lib/gitlab/diff/char_diff.rb
+++ b/lib/gitlab/diff/char_diff.rb
@@ -32,12 +32,12 @@ module Gitlab
           end
 
           if action == :delete
-            old_diffs << (old_pointer..(old_pointer + content_size - 1))
+            old_diffs << MarkerRange.new(old_pointer, old_pointer + content_size - 1, mode: MarkerRange::DELETION)
             old_pointer += content_size
           end
 
           if action == :insert
-            new_diffs << (new_pointer..(new_pointer + content_size - 1))
+            new_diffs << MarkerRange.new(new_pointer, new_pointer + content_size - 1, mode: MarkerRange::ADDITION)
             new_pointer += content_size
           end
         end
diff --git a/lib/gitlab/diff/highlight.rb b/lib/gitlab/diff/highlight.rb
index 035084d4861..baa46e7e306 100644
--- a/lib/gitlab/diff/highlight.rb
+++ b/lib/gitlab/diff/highlight.rb
@@ -31,6 +31,12 @@ module Gitlab
 
           if line_inline_diffs = inline_diffs[i]
             begin
+              # MarkerRange objects are converted to Ranges to keep the previous behavior
+              # Issue: https://gitlab.com/gitlab-org/gitlab/-/issues/324068
+              if Feature.disabled?(:introduce_marker_ranges, project, default_enabled: :yaml)
+                line_inline_diffs = line_inline_diffs.map { |marker_range| marker_range.to_range }
+              end
+
               rich_line = InlineDiffMarker.new(diff_line.text, rich_line).mark(line_inline_diffs)
             # This should only happen when the encoding of the diff doesn't
             # match the blob, which is a bug. But we shouldn't fail to render
@@ -67,7 +73,7 @@ module Gitlab
       end
 
       def inline_diffs
-        @inline_diffs ||= InlineDiff.for_lines(@raw_lines, project: project)
+        @inline_diffs ||= InlineDiff.for_lines(@raw_lines)
       end
 
       def old_lines
diff --git a/lib/gitlab/diff/highlight_cache.rb b/lib/gitlab/diff/highlight_cache.rb
index 7932cd2a837..c5e9bfdc321 100644
--- a/lib/gitlab/diff/highlight_cache.rb
+++ b/lib/gitlab/diff/highlight_cache.rb
@@ -7,8 +7,7 @@ module Gitlab
       include Gitlab::Utils::StrongMemoize
 
       EXPIRATION = 1.week
-      VERSION = 1
-      NEXT_VERSION = 2
+      VERSION = 2
 
       delegate :diffable,     to: :@diff_collection
       delegate :diff_options, to: :@diff_collection
@@ -70,20 +69,17 @@ module Gitlab
 
       def key
         strong_memoize(:redis_key) do
-          ['highlighted-diff-files', diffable.cache_key, version, diff_options].join(":")
+          [
+            'highlighted-diff-files',
+            diffable.cache_key, VERSION,
+            diff_options,
+            Feature.enabled?(:introduce_marker_ranges, diffable.project, default_enabled: :yaml)
+          ].join(":")
         end
       end
 
       private
 
-      def version
-        if Feature.enabled?(:improved_merge_diff_highlighting, diffable.project, default_enabled: :yaml)
-          NEXT_VERSION
-        else
-          VERSION
-        end
-      end
-
       def set_highlighted_diff_lines(diff_file, content)
         diff_file.highlighted_diff_lines = content.map do |line|
           Gitlab::Diff::Line.safe_init_from_hash(line)
diff --git a/lib/gitlab/diff/inline_diff.rb b/lib/gitlab/diff/inline_diff.rb
index cf769262958..dd73e4d6c15 100644
--- a/lib/gitlab/diff/inline_diff.rb
+++ b/lib/gitlab/diff/inline_diff.rb
@@ -3,22 +3,6 @@
 module Gitlab
   module Diff
     class InlineDiff
-      # Regex to find a run of deleted lines followed by the same number of added lines
-      LINE_PAIRS_PATTERN = %r{
-        # Runs start at the beginning of the string (the first line) or after a space (for an unchanged line)
-        (?:\A|\s)
-
-        # This matches a number of `-`s followed by the same number of `+`s through recursion
-        (?<del_ins>
-          -
-          \g<del_ins>?
-          \+
-        )
-
-        # Runs end at the end of the string (the last line) or before a space (for an unchanged line)
-        (?=\s|\z)
-      }x.freeze
-
       attr_accessor :old_line, :new_line, :offset
 
       def initialize(old_line, new_line, offset: 0)
@@ -27,28 +11,24 @@ module Gitlab
         @offset = offset
       end
 
-      def inline_diffs(project: nil)
+      def inline_diffs
         # Skip inline diff if empty line was replaced with content
         return if old_line == ""
 
-        if Feature.enabled?(:improved_merge_diff_highlighting, project, default_enabled: :yaml)
-          CharDiff.new(old_line, new_line).changed_ranges(offset: offset)
-        else
-          deprecated_diff
-        end
+        CharDiff.new(old_line, new_line).changed_ranges(offset: offset)
       end
 
       class << self
-        def for_lines(lines, project: nil)
-          changed_line_pairs = find_changed_line_pairs(lines)
+        def for_lines(lines)
+          pair_selector = Gitlab::Diff::PairSelector.new(lines)
 
           inline_diffs = []
 
-          changed_line_pairs.each do |old_index, new_index|
+          pair_selector.each do |old_index, new_index|
             old_line = lines[old_index]
             new_line = lines[new_index]
 
-            old_diffs, new_diffs = new(old_line, new_line, offset: 1).inline_diffs(project: project)
+            old_diffs, new_diffs = new(old_line, new_line, offset: 1).inline_diffs
 
             inline_diffs[old_index] = old_diffs
             inline_diffs[new_index] = new_diffs
@@ -56,74 +36,6 @@ module Gitlab
 
           inline_diffs
         end
-
-        private
-
-        # Finds pairs of old/new line pairs that represent the same line that changed
-        # rubocop: disable CodeReuse/ActiveRecord
-        def find_changed_line_pairs(lines)
-          # Prefixes of all diff lines, indicating their types
-          # For example: `" - +  -+  ---+++ --+  -++"`
-          line_prefixes = lines.each_with_object(+"") { |line, s| s << (line[0] || ' ') }.gsub(/[^ +-]/, ' ')
-
-          changed_line_pairs = []
-          line_prefixes.scan(LINE_PAIRS_PATTERN) do
-            # For `"---+++"`, `begin_index == 0`, `end_index == 6`
-            begin_index, end_index = Regexp.last_match.offset(:del_ins)
-
-            # For `"---+++"`, `changed_line_count == 3`
-            changed_line_count = (end_index - begin_index) / 2
-
-            halfway_index = begin_index + changed_line_count
-            (begin_index...halfway_index).each do |i|
-              # For `"---+++"`, index 1 maps to 1 + 3 = 4
-              changed_line_pairs << [i, i + changed_line_count]
-            end
-          end
-
-          changed_line_pairs
-        end
-        # rubocop: enable CodeReuse/ActiveRecord
-      end
-
-      private
-
-      # See: https://gitlab.com/gitlab-org/gitlab/-/issues/299884
-      def deprecated_diff
-        lcp = longest_common_prefix(old_line, new_line)
-        lcs = longest_common_suffix(old_line[lcp..-1], new_line[lcp..-1])
-
-        lcp += offset
-        old_length = old_line.length + offset
-        new_length = new_line.length + offset
-
-        old_diff_range = lcp..(old_length - lcs - 1)
-        new_diff_range = lcp..(new_length - lcs - 1)
-
-        old_diffs = [old_diff_range] if old_diff_range.begin <= old_diff_range.end
-        new_diffs = [new_diff_range] if new_diff_range.begin <= new_diff_range.end
-
-        [old_diffs, new_diffs]
-      end
-
-      def longest_common_prefix(a, b) # rubocop:disable Naming/UncommunicativeMethodParamName
-        max_length = [a.length, b.length].max
-
-        length = 0
-        (0..max_length - 1).each do |pos|
-          old_char = a[pos]
-          new_char = b[pos]
-
-          break if old_char != new_char
-
-          length += 1
-        end
-
-        length
-      end
-
-      def longest_common_suffix(a, b) # rubocop:disable Naming/UncommunicativeMethodParamName
-        longest_common_prefix(a.reverse, b.reverse)
       end
     end
   end
diff --git a/lib/gitlab/diff/inline_diff_markdown_marker.rb b/lib/gitlab/diff/inline_diff_markdown_marker.rb
index 3c536c43a9e..d8d596ebce7 100644
--- a/lib/gitlab/diff/inline_diff_markdown_marker.rb
+++ b/lib/gitlab/diff/inline_diff_markdown_marker.rb
@@ -8,8 +8,8 @@ module Gitlab
         deletion: "-"
       }.freeze
 
-      def mark(line_inline_diffs, mode: nil)
-        super(line_inline_diffs) do |text, left:, right:|
+      def mark(line_inline_diffs)
+        super(line_inline_diffs) do |text, left:, right:, mode:|
           symbol = MARKDOWN_SYMBOLS[mode]
           "{#{symbol}#{text}#{symbol}}"
         end
diff --git a/lib/gitlab/diff/inline_diff_marker.rb b/lib/gitlab/diff/inline_diff_marker.rb
index 29dff699ba5..c8cc1c0e649 100644
--- a/lib/gitlab/diff/inline_diff_marker.rb
+++ b/lib/gitlab/diff/inline_diff_marker.rb
@@ -7,8 +7,8 @@ module Gitlab
         super(line, rich_line || line)
       end
 
-      def mark(line_inline_diffs, mode: nil)
-        super(line_inline_diffs) do |text, left:, right:|
+      def mark(line_inline_diffs)
+        super(line_inline_diffs) do |text, left:, right:, mode:|
           %{<span class="#{html_class_names(left, right, mode)}">#{text}</span>}.html_safe
         end
       end
diff --git a/lib/gitlab/diff/pair_selector.rb b/lib/gitlab/diff/pair_selector.rb
new file mode 100644
index 00000000000..2e5ee3a7363
--- /dev/null
+++ b/lib/gitlab/diff/pair_selector.rb
@@ -0,0 +1,58 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Diff
+    class PairSelector
+      include Enumerable
+
+      # Regex to find a run of deleted lines followed by the same number of added lines
+      # rubocop: disable Lint/MixedRegexpCaptureTypes
+      LINE_PAIRS_PATTERN = %r{
+        # Runs start at the beginning of the string (the first line) or after a space (for an unchanged line)
+        (?:\A|\s)
+
+        # This matches a number of `-`s followed by the same number of `+`s through recursion
+        (?<del_ins>
+          -
+          \g<del_ins>?
+          \+
+        )
+
+        # Runs end at the end of the string (the last line) or before a space (for an unchanged line)
+        (?=\s|\z)
+      }x.freeze
+      # rubocop: enable Lint/MixedRegexpCaptureTypes
+
+      def initialize(lines)
+        @lines = lines
+      end
+
+      # Finds pairs of old/new line pairs that represent the same line that changed
+      # rubocop: disable CodeReuse/ActiveRecord
+      def each
+        # Prefixes of all diff lines, indicating their types
+        # For example: `" - +  -+  ---+++ --+  -++"`
+        line_prefixes = lines.each_with_object(+"") { |line, s| s << (line[0] || ' ') }.gsub(/[^ +-]/, ' ')
+
+        line_prefixes.scan(LINE_PAIRS_PATTERN) do
+          # For `"---+++"`, `begin_index == 0`, `end_index == 6`
+          begin_index, end_index = Regexp.last_match.offset(:del_ins)
+
+          # For `"---+++"`, `changed_line_count == 3`
+          changed_line_count = (end_index - begin_index) / 2
+
+          halfway_index = begin_index + changed_line_count
+          (begin_index...halfway_index).each do |i|
+            # For `"---+++"`, index 1 maps to 1 + 3 = 4
+            yield [i, i + changed_line_count]
+          end
+        end
+      end
+      # rubocop: enable CodeReuse/ActiveRecord
+
+      private
+
+      attr_reader :lines
+    end
+  end
+end