fix: do not throw when no dir (#48)

Author: Mark Wolff

packages/azure-opentelemetry-exporter/src/platform/nodejs/persist/fileSystemPersist.ts

@@ -59,7 +59,11 @@ export class FileSystemPersist implements PersistentStorage {
 
     fs.stat(tempDir, (statErr: Error | null, stats: fs.Stats) => {
       if (statErr) {
-        callback(statErr);
+        if (((statErr as unknown) as { code: string }).code === 'ENOENT') {
+          callback(null);
+        } else {
+          callback(statErr);
+        }
       } else if (stats.isDirectory()) {
         fs.readdir(tempDir, (error, origFiles) => {
           if (!error) {

packages/azure-opentelemetry-exporter/test/platform/nodejs/persist/fileSystemPersist.test.ts

@@ -94,15 +94,24 @@ describe('FileSystemPersist', () => {
   });
 
   describe('#shift()', () => {
+    it('should not crash if folder does not exist', (done) => {
+      const persister = new FileSystemPersist({ instrumentationKey });
+      persister.shift((err) => {
+        assert.strictEqual(err, null);
+        done();
+      });
+    });
+
     it('should not crash if file does not exist', (done) => {
       const persister = new FileSystemPersist({ instrumentationKey });
-      assert.doesNotThrow(() => {
+      fs.mkdir(tempDir, () => {
         persister.shift((err) => {
-          assert.ok(err);
+          assert.strictEqual(err, null);
           done();
         });
       });
     });
+
     it('should get the first file on disk and return it', (done) => {
       const persister = new FileSystemPersist({ instrumentationKey });