fix: compute patch size from additions only, ignore deletions

Copilot · pelikhan · web-flow · commit 435c47b7ca08 · 2026-04-01T12:17:15.000Z
Agent-Logs-Url: https://github.com/github/gh-aw/sessions/0ee9a48f-b693-487f-9b21-caecbf2e0c01 Co-authored-by: pelikhan <4175913+pelikhan@users.noreply.github.com>
diff --git a/actions/setup/js/push_repo_memory.cjs b/actions/setup/js/push_repo_memory.cjs
@@ -384,18 +384,23 @@ async function main() {
   }
 
   // Validate total patch size before committing
-  // Note: the patch size is the size of `git diff --cached`, which includes both the old (deleted)
-  // and new (added) content for each modified file. For files that are rewritten entirely, the
-  // patch can be significantly larger than the file itself (old_size + new_size + headers).
+  // Only additions (new content) are counted toward the patch size limit.
+  // Deletions are ignored since removing content is acceptable and does not
+  // contribute to the size of the content being pushed.
   try {
     const patchContent = execGitSync(["diff", "--cached"], { stdio: "pipe" });
-    const patchSizeBytes = Buffer.byteLength(patchContent, "utf8");
+    // Count only added lines (starting with '+', excluding '+++' file-header lines)
+    const addedSizeBytes = patchContent
+      .split("\n")
+      .filter(line => line.startsWith("+") && !line.startsWith("+++"))
+      .reduce((sum, line) => sum + Buffer.byteLength(line + "\n", "utf8"), 0);
+    const patchSizeBytes = addedSizeBytes;
     const patchSizeKb = Math.ceil(patchSizeBytes / 1024);
     const maxPatchSizeKb = Math.floor(maxPatchSize / 1024);
     // Allow 20% overhead to account for git diff format (headers, context lines, etc.)
     const effectiveMaxPatchSize = Math.floor(maxPatchSize * 1.2);
     const effectiveMaxPatchSizeKb = Math.floor(effectiveMaxPatchSize / 1024);
-    const patchSizeMessage = `Patch size: ${patchSizeKb} KB (${patchSizeBytes} bytes) (configured limit: ${maxPatchSizeKb} KB (${maxPatchSize} bytes), effective with 20% overhead: ${effectiveMaxPatchSizeKb} KB (${effectiveMaxPatchSize} bytes))`;
+    const patchSizeMessage = `Patch additions size: ${patchSizeKb} KB (${patchSizeBytes} bytes) (configured limit: ${maxPatchSizeKb} KB (${maxPatchSize} bytes), effective with 20% overhead: ${effectiveMaxPatchSizeKb} KB (${effectiveMaxPatchSize} bytes))`;
     if (patchSizeBytes > effectiveMaxPatchSize) {
       // Warn at warning level so the size is visible even without verbose mode
       core.warning(patchSizeMessage);
@@ -409,7 +414,7 @@ async function main() {
       }
       core.setOutput("patch_size_exceeded", "true");
       core.setFailed(
-        `Patch size (${patchSizeKb} KB, ${patchSizeBytes} bytes) exceeds maximum allowed size (${effectiveMaxPatchSizeKb} KB, ${effectiveMaxPatchSize} bytes, configured limit: ${maxPatchSizeKb} KB with 20% overhead allowance). Reduce the number or size of changes, or increase max-patch-size.`
+        `Patch additions size (${patchSizeKb} KB, ${patchSizeBytes} bytes) exceeds maximum allowed size (${effectiveMaxPatchSizeKb} KB, ${effectiveMaxPatchSize} bytes, configured limit: ${maxPatchSizeKb} KB with 20% overhead allowance). Reduce the number or size of changes, or increase max-patch-size.`
       );
       return;
     } else if (patchSizeBytes > maxPatchSize) {
@@ -419,7 +424,7 @@ async function main() {
       core.info(patchSizeMessage);
     }
   } catch (error) {
-    core.setFailed(`Failed to compute patch size: ${getErrorMessage(error)}`);
+    core.setFailed(`Failed to compute patch additions size: ${getErrorMessage(error)}`);
     return;
   }
 
