fix: electron crashing prematurely when window closes prematurely while browser launch process is ongoing

cli/CHANGELOG.md

@@ -12,6 +12,8 @@ _Released 07/05/2023 (PENDING)_
 - Fixed issues where commands would fail with the error `must only be invoked from the spec file or support file`. Fixes [#27149](https://github.com/cypress-io/cypress/issues/27149).
 - Fixed an issue where chrome was not recovering from browser crashes properly. Fixes [#24650](https://github.com/cypress-io/cypress/issues/24650).
 - Fixed a race condition that was causing a GraphQL error to appear on the [Debug page](https://docs.cypress.io/guides/cloud/runs#Debug) when viewing a running Cypress Cloud build. Fixed in [#27134](https://github.com/cypress-io/cypress/pull/27134).
+- Fixed a race condition in electron where the test window exiting prematurely during the browser launch process was causing the whole test run to fail. Addressed in [#27167](https://github.com/cypress-io/cypress/pull/27167).
+
 
 **Dependency Updates:**
 

packages/server/lib/browsers/electron.ts

@@ -159,25 +159,39 @@ export = {
         }
       },
       async onNewWindow (this: BrowserWindow, e, url) {
-        const _win = this
+        let _win: BrowserWindow | null = this
 
-        const child = await _this._launchChild(e, url, _win, projectRoot, state, options, automation)
-
-        // close child on parent close
-        _win.on('close', () => {
-          if (!child.isDestroyed()) {
-            child.destroy()
-          }
+        _win.on('closed', () => {
+          // in some cases, the browser/test will close before _launchChild completes, leaving a destroyed/stale window object.
+          // in these cases, we want to proceed to the next test/open window without critically failing
+          _win = null
         })
 
-        // add this pid to list of pids
-        tryToCall(child, () => {
-          if (instance && instance.pid) {
-            if (!instance.allPids) throw new Error('Missing allPids!')
-
-            instance.allPids.push(child.webContents.getOSProcessId())
+        try {
+          const child = await _this._launchChild(e, url, _win, projectRoot, state, options, automation)
+
+          // close child on parent close
+          _win.on('close', () => {
+            if (!child.isDestroyed()) {
+              child.destroy()
+            }
+          })
+
+          // add this pid to list of pids
+          tryToCall(child, () => {
+            if (instance && instance.pid) {
+              if (!instance.allPids) throw new Error('Missing allPids!')
+
+              instance.allPids.push(child.webContents.getOSProcessId())
+            }
+          })
+        } catch (e) {
+          if (_win === null) {
+            debug(`The window was closed while launching the child process. This usually means the browser or test errored before fully completing the launch process. Cypress will proceed to the next test`)
+          } else {
+            throw e
           }
-        })
+        }
       },
     }
 

system-tests/__snapshots__/browser_crash_handling_spec.js

@@ -403,3 +403,85 @@ This can happen for many different reasons:
 
 
 `
+
+exports['Browser Crash Handling / when the window closes mid launch of the browser process / passes'] = `
+
+====================================================================================================
+
+  (Run Starting)
+
+  ┌────────────────────────────────────────────────────────────────────────────────────────────────┐
+  │ Cypress:    1.2.3                                                                              │
+  │ Browser:    FooBrowser 88                                                                      │
+  │ Specs:      2 found (abort_beforeunload_event_child.cy.ts, abort_beforeunload_event.cy.ts)     │
+  │ Searched:   cypress/e2e/abort_beforeunload_event_child.cy.ts, cypress/e2e/abort_beforeunload_e │
+  │             vent.cy.ts                                                                         │
+  └────────────────────────────────────────────────────────────────────────────────────────────────┘
+
+
+────────────────────────────────────────────────────────────────────────────────────────────────────
+
+  Running:  abort_beforeunload_event_child.cy.ts                                            (1 of 2)
+
+
+  ✓ will exit even if an beforeload event dialog is present in a child window
+
+  1 passing
+
+
+  (Results)
+
+  ┌────────────────────────────────────────────────────────────────────────────────────────────────┐
+  │ Tests:        1                                                                                │
+  │ Passing:      1                                                                                │
+  │ Failing:      0                                                                                │
+  │ Pending:      0                                                                                │
+  │ Skipped:      0                                                                                │
+  │ Screenshots:  0                                                                                │
+  │ Video:        false                                                                            │
+  │ Duration:     X seconds                                                                        │
+  │ Spec Ran:     abort_beforeunload_event_child.cy.ts                                             │
+  └────────────────────────────────────────────────────────────────────────────────────────────────┘
+
+
+────────────────────────────────────────────────────────────────────────────────────────────────────
+
+  Running:  abort_beforeunload_event.cy.ts                                                  (2 of 2)
+
+
+  ✓ will exit even if an beforeload event dialog is present
+
+  1 passing
+
+
+  (Results)
+
+  ┌────────────────────────────────────────────────────────────────────────────────────────────────┐
+  │ Tests:        1                                                                                │
+  │ Passing:      1                                                                                │
+  │ Failing:      0                                                                                │
+  │ Pending:      0                                                                                │
+  │ Skipped:      0                                                                                │
+  │ Screenshots:  0                                                                                │
+  │ Video:        false                                                                            │
+  │ Duration:     X seconds                                                                        │
+  │ Spec Ran:     abort_beforeunload_event.cy.ts                                                   │
+  └────────────────────────────────────────────────────────────────────────────────────────────────┘
+
+
+====================================================================================================
+
+  (Run Finished)
+
+
+       Spec                                              Tests  Passing  Failing  Pending  Skipped  
+  ┌────────────────────────────────────────────────────────────────────────────────────────────────┐
+  │ ✔  abort_beforeunload_event_child.cy.t      XX:XX        1        1        -        -        - │
+  │    s                                                                                           │
+  ├────────────────────────────────────────────────────────────────────────────────────────────────┤
+  │ ✔  abort_beforeunload_event.cy.ts           XX:XX        1        1        -        -        - │
+  └────────────────────────────────────────────────────────────────────────────────────────────────┘
+    ✔  All specs passed!                        XX:XX        2        2        -        -        -  
+
+
+`

system-tests/projects/e2e/blocking_beforeunload_event.html

@@ -0,0 +1,9 @@
+<!DOCTYPE html>
+
+<script>
+  window.addEventListener('beforeunload', function (e) {
+    e.preventDefault();
+    e.returnValue = 'Dialog';
+    return;
+  })
+</script>

system-tests/projects/e2e/cypress/e2e/abort_beforeunload_event.cy.ts

@@ -0,0 +1,3 @@
+it('will exit even if an beforeload event dialog is present', function () {
+  cy.visit('/blocking_beforeunload_event.html')
+})

system-tests/projects/e2e/cypress/e2e/abort_beforeunload_event_child.cy.ts

@@ -0,0 +1,3 @@
+it('will exit even if an beforeload event dialog is present in a child window', function () {
+  cy.window().invoke('open', '/blocking_beforeunload_event.html')
+})

system-tests/test/browser_crash_handling_spec.js

@@ -67,4 +67,16 @@ describe('Browser Crash Handling', () => {
       expectedExitCode: 1,
     })
   })
+
+  context('when the window closes mid launch of the browser process', () => {
+    systemTests.it('passes', {
+      browser: 'electron',
+      spec: 'abort_beforeunload_event_child.cy.ts,abort_beforeunload_event.cy.ts',
+      snapshot: true,
+      expectedExitCode: 0,
+      config: {
+        video: false,
+      },
+    })
+  })
 })