v4.2.1

changelog.md

@@ -1,5 +1,21 @@
 # Changelog
 
+## 2026-03-05 - 4.2.1 - fix(compiler)
+use TypeScript sys hooks instead of fs monkeypatching to detect writes/deletes in previous output directories
+
+- Replace direct fs.* monkeypatching with interception of typescript.sys.writeFile, typescript.sys.deleteFile and typescript.sys.createDirectory
+- Add guards for optional sys.deleteFile before overriding it and preserve original sys methods to restore after compilation
+- Update diagnostic messages to reference TypeScript sys ops and add an informational message when no ops are observed
+- Reduce surface area of changes by avoiding global fs changes and focusing on TypeScript's sys API for safer interception
+
+## 2026-03-05 - 4.2.0 - feat(mod_compiler)
+add diagnostic interception of fs operations to detect and report unexpected file system changes in previously compiled output directories during compilation
+
+- Wraps fs.unlinkSync, fs.rmSync, fs.rmdirSync, fs.renameSync and fs.writeFileSync to record operations targeting other successful output directories during a compile.
+- Enabled only when there are previously compiled output dirs and when not running in quiet or JSON mode; original fs methods are restored after compilation.
+- Logs up to 30 intercepted operations and prints a summary count if any ops were observed; intercepted calls still perform the original fs action (diagnostic-only).
+- No functional change to compilation behavior beyond additional diagnostic reporting.
+
 ## 2026-03-05 - 4.1.26 - fix(compiler)
 fsync output directories after unpack to avoid XFS delayed logging causing corrupt or invisible directory entries during subsequent TypeScript emits
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@git.zone/tsbuild",
-  "version": "4.1.26",
+  "version": "4.2.1",
   "private": false,
   "description": "A tool for compiling TypeScript files using the latest nightly features, offering flexible APIs and a CLI for streamlined development.",
   "main": "dist_ts/index.js",

ts/00_commitinfo_data.ts

@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@git.zone/tsbuild',
-  version: '4.1.26',
+  version: '4.2.1',
   description: 'A tool for compiling TypeScript files using the latest nightly features, offering flexible APIs and a CLI for streamlined development.'
 }

ts/mod_compiler/classes.tscompiler.ts

@@ -380,9 +380,57 @@ export class TsCompiler {
         fileCount: absoluteFiles.length,
       };
 
+      // Diagnostic: intercept TypeScript sys operations during compilation to detect
+      // any unexpected writes/deletes in previously compiled output directories
+      const watchedDirs = successfulOutputDirs.filter(d => d !== destDir);
+      let interceptedOps: string[] = [];
+      const origSysWriteFile = typescript.sys.writeFile;
+      const origSysDeleteFile = typescript.sys.deleteFile;
+      const origSysCreateDir = typescript.sys.createDirectory;
+      if (watchedDirs.length > 0 && !isQuiet && !isJson) {
+        typescript.sys.writeFile = (p: string, data: string, writeBom?: boolean) => {
+          if (watchedDirs.some(d => p.startsWith(d + '/'))) {
+            interceptedOps.push(`sys.writeFile: ${p}`);
+          }
+          return origSysWriteFile.call(typescript.sys, p, data, writeBom);
+        };
+        if (origSysDeleteFile) {
+          typescript.sys.deleteFile = (p: string) => {
+            if (watchedDirs.some(d => p.startsWith(d + '/'))) {
+              interceptedOps.push(`sys.deleteFile: ${p}`);
+            }
+            return origSysDeleteFile!.call(typescript.sys, p);
+          };
+        }
+        typescript.sys.createDirectory = (p: string) => {
+          if (watchedDirs.some(d => p.startsWith(d + '/'))) {
+            interceptedOps.push(`sys.createDirectory: ${p}`);
+          }
+          return origSysCreateDir.call(typescript.sys, p);
+        };
+      }
+
       const result = await this.compileFiles(absoluteFiles, options, taskInfo);
       emittedFiles.push(...result.emittedFiles);
       errorSummaries.push(result.errorSummary);
+
+      // Restore original sys methods and report any intercepted operations
+      if (watchedDirs.length > 0 && !isQuiet && !isJson) {
+        typescript.sys.writeFile = origSysWriteFile;
+        typescript.sys.deleteFile = origSysDeleteFile;
+        typescript.sys.createDirectory = origSysCreateDir;
+        if (interceptedOps.length > 0) {
+          console.log(`   ⚠️ [diag] ${interceptedOps.length} TypeScript sys ops on previous output dirs:`);
+          for (const op of interceptedOps.slice(0, 30)) {
+            console.log(`      ${op.replace(this.cwd + '/', '')}`);
+          }
+          if (interceptedOps.length > 30) {
+            console.log(`      ... and ${interceptedOps.length - 30} more`);
+          }
+        } else {
+          console.log(`   ℹ️ [diag] No TypeScript sys ops on previous output dirs during this compilation`);
+        }
+      }
       diagSnap('post-compile');
 
       // Diagnostic: log emitted files that went to unexpected directories