fix: Add container detection for other container runtimes

src/lib/is-docker.ts

@@ -1,8 +1,9 @@
 const fs = require('fs');
 
 export function isDocker(): boolean {
-  return hasDockerEnv() || hasDockerCGroup();
+  return hasDockerEnv() || hasContainerEnv() || hasDockerCGroup();
 }
+
 function hasDockerEnv() {
   try {
     fs.statSync('/.dockerenv');
@@ -12,6 +13,15 @@ function hasDockerEnv() {
   }
 }
 
+function hasContainerEnv() {
+  try {
+    fs.statSync('/run/.containerenv');
+    return true;
+  } catch (_) {
+    return false;
+  }
+}
+
 function hasDockerCGroup() {
   try {
     return fs.readFileSync('/proc/self/cgroup', 'utf8').includes('docker');

test/jest/unit/is-docker.spec.ts

@@ -16,6 +16,25 @@ describe('isDocker', () => {
     expect(statSyncSpy).toHaveBeenLastCalledWith('/.dockerenv');
   });
 
+  it('inside other containers (.containerenv test)', async () => {
+    delete require.cache[path.join(__dirname, 'index.js')];
+    const statSyncSpy = jest.spyOn(fs, 'statSync');
+
+    statSyncSpy.mockImplementationOnce((path): any => {
+      if (path === '/.dockerenv') {
+        throw new Error("ENOENT, no such file or directory '/.dockerinit'");
+      }
+
+      if (path === '/run/.containerenv') {
+        return {} as any
+      }
+    });
+    expect(isDocker()).toBeTruthy();
+    expect(statSyncSpy).toHaveBeenCalledTimes(2);
+    expect(statSyncSpy).toHaveBeenLastCalledWith('/run/.containerenv');
+  });
+
+
   it('inside a Docker container (cgroup test)', async () => {
     delete require.cache[path.join(__dirname, 'index.js')];