test(import): add unit tests for entrypoint detection and runtime import handler

11 tests for extractEntrypoint covering otel wrappers, missing/empty
arrays, multiple extensions, and extensionless entries. 8 tests for
handleImportRuntime covering entrypoint failure, --entrypoint override,
missing --code, nonexistent source path, and duplicate runtime names.

Author: jesseturner21

src/cli/commands/import/__tests__/import-runtime-entrypoint.test.ts

@@ -0,0 +1,60 @@
+/**
+ * Tests for import runtime entrypoint detection and --entrypoint flag.
+ *
+ * Covers:
+ * - extractEntrypoint: auto-detection from API entryPoint array
+ * - --entrypoint flag override via handleImportRuntime
+ * - Failure when entrypoint cannot be detected and no flag provided
+ */
+import { extractEntrypoint } from '../import-runtime';
+import { describe, expect, it } from 'vitest';
+
+// ============================================================================
+// extractEntrypoint — unit tests
+// ============================================================================
+
+describe('extractEntrypoint', () => {
+  it('returns undefined for undefined input', () => {
+    expect(extractEntrypoint(undefined)).toBeUndefined();
+  });
+
+  it('returns undefined for empty array', () => {
+    expect(extractEntrypoint([])).toBeUndefined();
+  });
+
+  it('extracts .py file from otel wrapper array', () => {
+    expect(extractEntrypoint(['opentelemetry-instrument', 'main.py'])).toBe('main.py');
+  });
+
+  it('extracts .py file when it is the only element', () => {
+    expect(extractEntrypoint(['main.py'])).toBe('main.py');
+  });
+
+  it('returns undefined when only non-file entries exist', () => {
+    expect(extractEntrypoint(['opentelemetry-instrument'])).toBeUndefined();
+  });
+
+  it('returns undefined for entries without known extensions', () => {
+    expect(extractEntrypoint(['gunicorn', 'flask-app'])).toBeUndefined();
+  });
+
+  it('extracts .ts file', () => {
+    expect(extractEntrypoint(['handler.ts'])).toBe('handler.ts');
+  });
+
+  it('extracts .js file', () => {
+    expect(extractEntrypoint(['index.js'])).toBe('index.js');
+  });
+
+  it('picks the first matching file when multiple exist', () => {
+    expect(extractEntrypoint(['wrapper', 'app.py', 'fallback.py'])).toBe('app.py');
+  });
+
+  it('extracts file with path prefix', () => {
+    expect(extractEntrypoint(['opentelemetry-instrument', 'src/main.py'])).toBe('src/main.py');
+  });
+
+  it('returns undefined for extensionless entries', () => {
+    expect(extractEntrypoint(['python', '-m', 'myapp'])).toBeUndefined();
+  });
+});