hanlding empty override file.

Co-authored-by: Copilot <copilot@github.com>

Author: EMaher

src/lib/config-loader.ts

@@ -32,7 +32,7 @@ function assertStringArray(value: unknown, fieldName: string): string[] {
 export async function loadFilterConfig(filePath: string): Promise<FilterConfig | undefined> {
   try {
     const content = await fs.readFile(filePath, 'utf-8');
-    const parsed = yaml.load(content) as Record<string, unknown>;
+    const parsed = yaml.load(content) as Record<string, unknown> ?? {};
 
     // Validate structure — each field must be an array of strings
     const config: FilterConfig = {};
@@ -104,13 +104,10 @@ export async function loadFilterConfig(filePath: string): Promise<FilterConfig |
 export async function loadOverrideConfig(filePath: string): Promise<OverrideConfig | undefined> {
   try {
     const content = await fs.readFile(filePath, 'utf-8');
-    const parsed = yaml.load(content) as Record<string, unknown>;
-    
-    // Return as-is; validation will happen during publish when applied
-    const config = parsed as OverrideConfig;
+    const parsed = (yaml.load(content) ?? {}) as OverrideConfig;
 
     logger.debug(`Loaded override config from ${filePath}`);
-    return config;
+    return parsed;
   } catch (error) {
     if ((error as NodeJS.ErrnoException).code === 'ENOENT') {
       logger.debug(`Override config file not found: ${filePath}`);
@@ -127,7 +124,7 @@ export async function loadOverrideConfig(filePath: string): Promise<OverrideConf
 export async function loadOTelConfig(filePath: string): Promise<Record<string, unknown> | undefined> {
   try {
     const content = await fs.readFile(filePath, 'utf-8');
-    const parsed = yaml.load(content) as Record<string, unknown>;
+    const parsed = yaml.load(content) as Record<string, unknown> ?? {};
 
     logger.debug(`Loaded OTel config from ${filePath}`);
     return parsed;

tests/unit/lib/config-loader.test.ts

@@ -49,6 +49,24 @@ tagNames:
       expect(config).toBeDefined();
     });
 
+    it('should handle completely empty file', async () => {
+      const filePath = path.join(tmpDir, 'blank.yaml');
+      await fs.writeFile(filePath, '', 'utf-8');
+
+      const config = await loadFilterConfig(filePath);
+      expect(config).toBeDefined();
+      expect(config).toEqual({});
+    });
+
+    it('should handle file with only comments', async () => {
+      const filePath = path.join(tmpDir, 'comments.yaml');
+      await fs.writeFile(filePath, '# This is a comment\n# Another comment', 'utf-8');
+
+      const config = await loadFilterConfig(filePath);
+      expect(config).toBeDefined();
+      expect(config).toEqual({});
+    });
+
     it('should throw for invalid type (non-array field)', async () => {
       const content = `
 apiNames: "not-an-array"
@@ -123,6 +141,24 @@ backends:
       const config = await loadOverrideConfig(path.join(tmpDir, 'nonexistent.yaml'));
       expect(config).toBeUndefined();
     });
+
+    it('should handle completely empty file', async () => {
+      const filePath = path.join(tmpDir, 'blank.yaml');
+      await fs.writeFile(filePath, '', 'utf-8');
+
+      const config = await loadOverrideConfig(filePath);
+      expect(config).toBeDefined();
+      expect(config).toEqual({});
+    });
+
+    it('should handle file with only comments', async () => {
+      const filePath = path.join(tmpDir, 'comments.yaml');
+      await fs.writeFile(filePath, '# Override config\n# TODO: add overrides', 'utf-8');
+
+      const config = await loadOverrideConfig(filePath);
+      expect(config).toBeDefined();
+      expect(config).toEqual({});
+    });
   });
 
   describe('loadOTelConfig', () => {
@@ -148,5 +184,23 @@ service:
       const config = await loadOTelConfig(path.join(tmpDir, 'nonexistent.yaml'));
       expect(config).toBeUndefined();
     });
+
+    it('should handle completely empty file', async () => {
+      const filePath = path.join(tmpDir, 'blank.yaml');
+      await fs.writeFile(filePath, '', 'utf-8');
+
+      const config = await loadOTelConfig(filePath);
+      expect(config).toBeDefined();
+      expect(config).toEqual({});
+    });
+
+    it('should handle file with only whitespace', async () => {
+      const filePath = path.join(tmpDir, 'whitespace.yaml');
+      await fs.writeFile(filePath, '   \n  \n  ', 'utf-8');
+
+      const config = await loadOTelConfig(filePath);
+      expect(config).toBeDefined();
+      expect(config).toEqual({});
+    });
   });
 });