Chore: short circut output content hash comparision on CI

Build/lib/writing-strategy/base.ts

@@ -1,6 +1,7 @@
+import { isCI } from 'ci-info';
 import type { Span } from '../../trace';
 import { calculateContentHash } from '../content-hash';
-import { compareAndWriteFile } from '../create-file';
+import { compareAndWriteFile, writeFileLines } from '../create-file';
 
 /**
  * The class is not about holding rule data, instead it determines how the
@@ -27,6 +28,14 @@ export abstract class BaseWriteStrategy {
 
   protected abstract result: string[] | null;
 
+  /**
+   * Whether the output has no volatile metadata (e.g. "Last Updated") to preserve,
+   * so on CI the previous file can simply be overwritten without comparison (the
+   * comparison would only serve to reduce SSD wear, which CI doesn't care about).
+   * Only enable this when withPadding emits neither a banner nor any date.
+   */
+  protected readonly skipCompareOnCI: boolean = false;
+
   abstract writeDomain(domain: string): void;
   abstract writeDomainSuffix(domain: string): void;
   abstract writeDomainKeywords(keyword: Set<string>): void;
@@ -59,6 +68,16 @@ export abstract class BaseWriteStrategy {
       return;
     }
 
+    // Without volatile metadata to preserve, the compare-before-write only serves
+    // to reduce SSD wear -- irrelevant on CI, so skip hashing and comparison alike.
+    if (isCI && this.skipCompareOnCI) {
+      return writeFileLines(
+        span,
+        this.withPadding(title, description, date, result, null),
+        filePath
+      );
+    }
+
     // The hash covers the real content (title, description and rules) but not the
     // volatile date, so compareAndWriteFile can bail out by only reading the head
     // of the previous output. Strategies whose withPadding doesn't embed the marker

Build/lib/writing-strategy/singbox.ts

@@ -34,6 +34,9 @@ export class SingboxSource extends BaseWriteStrategy {
 
   static readonly jsonToLines = (json: unknown): string[] => stringify(json).split('\n');
 
+  // JSON output has no metadata comment at all, nothing to preserve
+  protected override readonly skipCompareOnCI = true;
+
   private readonly singbox: SingboxHeadlessRule = {
     domain: [MARKER_DOMAIN],
     domain_suffix: [MARKER_DOMAIN]

Build/lib/writing-strategy/surge.ts

@@ -154,6 +154,9 @@ export class SurgeMitmSgmodule extends BaseWriteStrategy {
 
   private readonly rules = new Set<string>();
 
+  // #!desc only carries a size derived from the rules, no volatile date
+  protected override readonly skipCompareOnCI = true;
+
   protected get result() {
     if (this.rules.size === 0) {
       return null;