refactor(lazygit): limit autosquash scan window

Keep the autosquash command's automatic oldest-target detection, but stop it from scanning arbitrarily deep history.

Scan only the last 100 commits from HEAD when resolving fixup!/squash! commits, then rebase from the parent of the oldest matched target in that window.

This preserves the existing behavior for recent work while avoiding huge rebases and unrelated conflicts in repositories that still contain older unsquashed fixup commits.

Author: khaneliman

modules/home/programs/terminal/tools/lazygit/custom-commands.nix

@@ -27,6 +27,8 @@
         exit 1
       fi
 
+      maxScanCommits=100
+
       workDir="''${TMPDIR:-/tmp}/lazygit-autosquash-$$"
       rm -rf "$workDir"
       mkdir -p "$workDir"
@@ -42,7 +44,7 @@
       : > "$orderFile"
       : > "$usedFile"
 
-      git --no-pager log --reverse --format='%H%x09%s' HEAD > "$historyFile"
+      git --no-pager log --reverse -n "$maxScanCommits" --format='%H%x09%s' HEAD > "$historyFile"
 
       fixupCount=0
       resolvedCount=0
@@ -84,12 +86,12 @@
       done < "$historyFile"
 
       if [ "$fixupCount" -eq 0 ]; then
-        echo "No fixup!/squash! commits found on this branch."
+        echo "No fixup!/squash! commits found in the last $maxScanCommits commits."
         exit 1
       fi
 
       if [ "$resolvedCount" -eq 0 ]; then
-        echo "Found fixup!/squash! commits, but could not resolve target commits."
+        echo "Found fixup!/squash! commits in the last $maxScanCommits commits, but none target commits in that window."
         exit 1
       fi
 
@@ -121,15 +123,15 @@
         GIT_SEQUENCE_EDITOR=: git rebase -i --autosquash --no-verify --root
       fi
     '';
-    description = "Autosquash all fixup/squash commits (auto-detect oldest target, skip hooks)";
+    description = "Autosquash recent fixup/squash commits (last 100 commits)";
     loadingText = "Autosquashing fixup commits...";
     output = "log";
     prompts = [
       {
         type = "confirm";
         key = "ConfirmAutosquash";
         title = "Rewrite commit history?";
-        body = "This auto-detects the oldest fixup target commit, rebases from its parent, and rewrites commit hashes.";
+        body = "This searches the last 100 commits, rebases from the oldest fixup target it finds, and rewrites commit hashes.";
       }
     ];
   }