process: wait for 'exit' before printing result

Co-authored-by: Vinícius Lourenço <contact@viniciusl.com.br>
Co-authored-by: Antoine du Hamel <duhamelantoine1995@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/52172
Refs: https://github.com/nodejs/node/pull/52077
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Vinícius Lourenço Claro Cardoso <contact@viniciusl.com.br>
Reviewed-By: Chemi Atlow <chemi@atlow.co.il>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>

lib/internal/process/execution.js

@@ -119,7 +119,10 @@ function evalScript(name, body, breakFirstLine, print, shouldLoadESM = false) {
     });
     if (print) {
       const { log } = require('internal/console/global');
-      log(result);
+
+      process.on('exit', () => {
+        log(result);
+      });
     }
 
     if (origModule !== undefined)

test/parallel/test-cli-print-promise.mjs

@@ -29,7 +29,7 @@ describe('--print with a promise', { concurrency: !process.env.TEST_PARALLEL },
       code: 0,
       signal: null,
       stderr: '',
-      stdout: 'Promise { <pending> }\n',
+      stdout: 'Promise { 42 }\n',
     });
   });
 
@@ -50,7 +50,7 @@ describe('--print with a promise', { concurrency: !process.env.TEST_PARALLEL },
   it('should output something if process exits before promise settles', async () => {
     const result = await spawnPromisified(execPath, [
       '--print',
-      'setTimeout(process.exit,100, 0);timers.promises.setTimeout(200)',
+      'setTimeout(process.exit, 100, 0);timers.promises.setTimeout(200)',
     ]);
 
     assert.deepStrictEqual(result, {
@@ -61,6 +61,20 @@ describe('--print with a promise', { concurrency: !process.env.TEST_PARALLEL },
     });
   });
 
+  it('should respect exit code when process exits before promise settles', async () => {
+    const result = await spawnPromisified(execPath, [
+      '--print',
+      'setTimeout(process.exit, 100, 42);timers.promises.setTimeout(200)',
+    ]);
+
+    assert.deepStrictEqual(result, {
+      code: 42,
+      signal: null,
+      stderr: '',
+      stdout: 'Promise { <pending> }\n',
+    });
+  });
+
   it('should handle rejected promises', async () => {
     const result = await spawnPromisified(execPath, [
       '--unhandled-rejections=none',
@@ -87,7 +101,52 @@ describe('--print with a promise', { concurrency: !process.env.TEST_PARALLEL },
       code: 0,
       signal: null,
       stderr: '',
-      stdout: 'Promise { <pending> }\n',
+      stdout: 'Promise { <rejected> 1 }\n',
+    });
+  });
+
+  it('should handle thenable that resolves', async () => {
+    const result = await spawnPromisified(execPath, [
+      '--unhandled-rejections=none',
+      '--print',
+      '({ then(r) { r(42) } })',
+    ]);
+
+    assert.deepStrictEqual(result, {
+      code: 0,
+      signal: null,
+      stderr: '',
+      stdout: '{ then: [Function: then] }\n',
+    });
+  });
+
+  it('should handle thenable that rejects', async () => {
+    const result = await spawnPromisified(execPath, [
+      '--unhandled-rejections=none',
+      '--print',
+      '({ then(_, r) { r(42) } })',
+    ]);
+
+    assert.deepStrictEqual(result, {
+      code: 0,
+      signal: null,
+      stderr: '',
+      stdout: '{ then: [Function: then] }\n',
+    });
+  });
+
+  it('should handle Promise.prototype', async () => {
+    const result = await spawnPromisified(execPath, [
+      '--unhandled-rejections=none',
+      '--print',
+      'Promise.prototype',
+    ]);
+
+    assert.deepStrictEqual(result, {
+      code: 0,
+      signal: null,
+      stderr: '',
+      stdout: 'Object [Promise] {}\n',
     });
   });
 });