WIP: smarter edit algorithm

SamSaffron · SamSaffron · commit 8e2ffaed23d4 · 2025-02-19T14:32:57.000+11:00
diff --git a/lib/ai_bot/artifact_update_strategies/diff.rb b/lib/ai_bot/artifact_update_strategies/diff.rb
@@ -98,16 +98,18 @@ def system_prompt
 
             1. Use EXACTLY this format for changes:
                <<<<<<< SEARCH
-               (exact code to find)
+               (first line of code to replace)
+               (other lines of code to avoid ambiguity)
+               (last line of code to replace)
                =======
                (replacement code)
                >>>>>>> REPLACE
             2. DO NOT modify the markers or add spaces around them
             3. DO NOT add explanations or comments within sections
             4. ONLY include [HTML], [CSS], and [JavaScript] sections if they have changes
-            5. Ensure search text matches EXACTLY - partial matches will fail
-            6. Keep changes minimal and focused
-            7. HTML should not include <html>, <head>, or <body> tags, it is injected into a template
+            5. Keep changes minimal and focused
+            6. HTML should not include <html>, <head>, or <body> tags, it is injected into a template
+            7. When specifying a SEARCH block, ALWAYS keep it 8 lines or less, you will be interrupted and a retry will be required if you exceed this limit
 
             JavaScript libraries must be sourced from the following CDNs, otherwise CSP will reject it:
             #{AiArtifact::ALLOWED_CDN_SOURCES.join("\n")}
diff --git a/lib/utils/diff_utils/simple_diff.rb b/lib/utils/diff_utils/simple_diff.rb
@@ -26,6 +26,8 @@ def apply(content, search, replace)
           lines = content.split("\n")
           search_lines = search.split("\n")
 
+          ### TODO implement me
+
           # 1. Try exact matching
           match_positions =
             find_matches(lines, search_lines) { |line, search_line| line == search_line }
@@ -38,15 +40,25 @@ def apply(content, search, replace)
               end
           end
 
-          # 3. Try fuzzy matching
+          # 3. Try non-contiguous line based stripped matching
+          if match_positions.empty?
+            if range = non_contiguous_match_range(lines, search_lines)
+              first_match, last_match = range
+              lines.slice!(first_match, last_match - first_match + 1)
+              lines.insert(first_match, *replace.split("\n"))
+              return lines.join("\n")
+            end
+          end
+
+          # 4. Try fuzzy matching
           if match_positions.empty?
             match_positions =
               find_matches(lines, search_lines) do |line, search_line|
                 fuzzy_match?(line, search_line)
               end
           end
 
-          # 4. Try block matching as last resort
+          # 5. Try block matching as last resort
           if match_positions.empty?
             if block_matches = find_block_matches(content, search)
               return replace_blocks(content, block_matches, replace)
@@ -68,6 +80,23 @@ def apply(content, search, replace)
 
         private
 
+        def non_contiguous_match_range(lines, search_lines)
+          first_idx = nil
+          last_idx = nil
+          search_index = 0
+
+          lines.each_with_index do |line, idx|
+            if line.strip == search_lines[search_index].strip
+              first_idx ||= idx
+              last_idx = idx
+              search_index += 1
+              return first_idx, last_idx if search_index == search_lines.length
+            end
+          end
+
+          nil
+        end
+
         def find_matches(lines, search_lines)
           matches = []
           max_index = lines.length - search_lines.length
diff --git a/spec/lib/utils/diff_utils/simple_diff_spec.rb b/spec/lib/utils/diff_utils/simple_diff_spec.rb
@@ -171,5 +171,31 @@
 
       expect(subject.apply(content, search, replace).strip).to eq(expected.strip)
     end
+
+    it "handles missing lines in search" do
+      original = <<~TEXT
+        line1
+         line2
+        line3
+        line4
+        line5
+        line1
+        line2
+      TEXT
+
+      search = <<~TEXT
+        line1
+         line3
+        line1
+      TEXT
+
+      replace = ""
+
+      expected = <<~TEXT
+        line2
+      TEXT
+
+      expect(subject.apply(original, search, replace).strip).to eq(expected.strip)
+    end
   end
 end
