fixed multiline test failing

Author: proggod

src/core/diff/strategies/multi-search-replace.ts

@@ -241,28 +241,28 @@ Only use a single line of '=======' between search and replacement content, beca
 			  Ensures the first marker starts at the beginning of the file or right after a newline.
 
 			2. (?<!\\)<<<<<<< SEARCH\s*\n  
-			  Matches the line "<<<<<<< SEARCH" (ignoring any trailing spaces) – the negative lookbehind makes sure it isn't escaped.
+			  Matches the line “<<<<<<< SEARCH” (ignoring any trailing spaces) – the negative lookbehind makes sure it isn’t escaped.
 
 			3. ((?:\:start_line:\s*(\d+)\s*\n))?  
-			  Optionally matches a ":start_line:" line. The outer capturing group is group 1 and the inner (\d+) is group 2.
+			  Optionally matches a “:start_line:” line. The outer capturing group is group 1 and the inner (\d+) is group 2.
 
 			4. ((?:\:end_line:\s*(\d+)\s*\n))?  
-			  Optionally matches a ":end_line:" line. Group 3 is the whole match and group 4 is the digits.
+			  Optionally matches a “:end_line:” line. Group 3 is the whole match and group 4 is the digits.
 
 			5. ((?<!\\)-------\s*\n)?  
-			  Optionally matches the "-------" marker line (group 5).
+			  Optionally matches the “-------” marker line (group 5).
 
 			6. ([\s\S]*?)(?:\n)?  
-			  Non‐greedy match for the "search content" (group 6) up to the next marker.
+			  Non‐greedy match for the “search content” (group 6) up to the next marker.
 
 			7. (?:(?<=\n)(?<!\\)=======\s*\n)  
-			  Matches the "=======" marker on its own line.
+			  Matches the “=======” marker on its own line.
 
 			8. ([\s\S]*?)(?:\n)?  
-			  Non‐greedy match for the "replace content" (group 7).
+			  Non‐greedy match for the “replace content” (group 7).
 
 			9. (?:(?<=\n)(?<!\\)>>>>>>> REPLACE)(?=\n|$)  
-			  Matches the final ">>>>>>> REPLACE" marker on its own line (and requires a following newline or the end of file).
+			  Matches the final “>>>>>>> REPLACE” marker on its own line (and requires a following newline or the end of file).
 		*/
 
 		let matches = [
@@ -300,9 +300,11 @@ Only use a single line of '=======' between search and replacement content, beca
 			searchContent = this.unescapeMarkers(searchContent)
 			replaceContent = this.unescapeMarkers(replaceContent)
 
-			// Strip line numbers from search and replace content
-			searchContent = stripLineNumbers(searchContent)
-			replaceContent = stripLineNumbers(replaceContent)
+			// Strip line numbers from search and replace content if every line starts with a line number
+			if (everyLineHasLineNumbers(searchContent) && everyLineHasLineNumbers(replaceContent)) {
+				searchContent = stripLineNumbers(searchContent)
+				replaceContent = stripLineNumbers(replaceContent)
+			}
 
 			// Validate that search and replace content are not identical
 			if (searchContent === replaceContent) {