perf(fslib): reduce fs calls in findZip

Author: merceyz

.pnp.js

@@ -11,6 +11,8 @@ import {Filename, FSPath, PortablePath}
 
 const ZIP_FD = 0x80000000;
 
+const FILE_PARTS_REGEX = /.*?(?<!\/|\\)\.zip(?=\/|\\|$)/;
+
 export type ZipOpenFSOptions = {
   baseFs?: FakeFS<PortablePath>,
   filter?: RegExp | null,
@@ -59,9 +61,6 @@ export class ZipOpenFS extends BasePortableFakeFS {
     this.filter = filter;
     this.maxOpenFiles = maxOpenFiles;
     this.readOnlyArchives = readOnlyArchives;
-
-    this.isZip = new Set();
-    this.notZip = new Set();
   }
 
   getExtractHint(hints: ExtractHintOptions) {
@@ -687,51 +686,34 @@ export class ZipOpenFS extends BasePortableFakeFS {
   }
 
   private findZip(p: PortablePath) {
-    if (this.filter && !this.filter.test(p))
-      return null;
-
-    const parts = p.split(/\//g);
+    if (this.filter && !this.filter.test(p)) return null;
 
-    for (let t = 2; t <= parts.length; ++t) {
-      const archivePath = parts.slice(0, t).join(`/`) as PortablePath;
+    let filePath = `` as PortablePath;
 
-      if (this.notZip.has(archivePath))
-        continue;
+    while (true) {
+      const parts = FILE_PARTS_REGEX.exec(p.substr(filePath.length));
+      if (!parts)
+        return null;
 
-      if (this.isZip.has(archivePath))
-        return {archivePath, subPath: this.pathUtils.resolve(PortablePath.root, parts.slice(t).join(`/`) as PortablePath)};
+      filePath = this.pathUtils.join(filePath, parts[0] as PortablePath);
 
-      let realArchivePath = archivePath;
-      let stat;
+      if (this.isZip.has(filePath) === false) {
+        if (this.notZip.has(filePath))
+          continue;
 
-      while (true) {
-        try {
-          stat = this.baseFs.lstatSync(realArchivePath);
-        } catch (error) {
-          return null;
+        if (this.baseFs.lstatSync(filePath).isFile() === false) {
+          this.notZip.add(filePath);
+          continue;
         }
 
-        if (stat.isSymbolicLink()) {
-          realArchivePath = this.pathUtils.resolve(this.pathUtils.dirname(realArchivePath), this.baseFs.readlinkSync(realArchivePath));
-        } else {
-          break;
-        }
+        this.isZip.add(filePath);
       }
 
-      const isZip = stat.isFile() && this.pathUtils.extname(realArchivePath) === `.zip`;
-
-      if (isZip) {
-        this.isZip.add(archivePath);
-        return {archivePath, subPath: this.pathUtils.resolve(PortablePath.root, parts.slice(t).join(`/`) as PortablePath)};
-      } else {
-        this.notZip.add(archivePath);
-        if (stat.isFile()) {
-          return null;
-        }
-      }
+      return {
+        archivePath: filePath,
+        subPath: this.pathUtils.resolve(PortablePath.root, p.substr(filePath.length) as PortablePath),
+      };
     }
-
-    return null;
   }
 
   private limitOpenFiles(max: number) {