⚡️ Speed up function get_diff_lines_count by 16% in PR #284 (saga4/fix_duplication_suggestion_issue)

Here's a faster version of your program. The main bottleneck is the list comprehension calling a nested function for every line, leading to relatively high overhead. Avoiding the inner function, only iterating once, and not building an intermediate list (since we only need the count) can significantly improve performance.

You do **not** need to build the list of lines; simply scan and count qualifying lines in a single pass.

Optimized version.



**Changes made:**
- Inlined the `is_diff_line` logic for better performance (function call overhead avoided).
- Used a running integer (`count`) instead of a list, so memory use and processing are reduced.
- Avoided creating an unnecessary list and removed the nested function.

**This is as fast and memory-efficient as this logic gets in idiomatic Python.**

Author: codeflash-ai[bot]

codeflash/code_utils/formatter.py

@@ -24,13 +24,12 @@ def get_diff_output_by_black(filepath: str, unformatted_content: str) -> Optiona
 
 
 def get_diff_lines_count(diff_output: str) -> int:
-    lines = diff_output.split("\n")
-
-    def is_diff_line(line: str) -> bool:
-        return line.startswith(("+", "-")) and not line.startswith(("+++", "---"))
-
-    diff_lines = [line for line in lines if is_diff_line(line)]
-    return len(diff_lines)
+    # Count only the diff lines as per is_diff_line logic, but avoid unnecessary function call and list allocation.
+    count = 0
+    for line in diff_output.split("\n"):
+        if line and line[0] in "+-" and not (line.startswith("+++") or line.startswith("---")):
+            count += 1
+    return count
 
 
 def is_safe_to_format(filepath: str, content: str, max_diff_lines: int = 100) -> bool: