Fix: stop all active spinners on reporter.close() (#4150)

**Summary**

We were not stopping any activities in the reporter and were
relying on `process.exit()` to kill them earlier. This patch
fixes that and ensures all activities are stopped when the
reporter is closed.

**Test plan**

Adds a new snapshots test that fails without the fix.

Manual: just try to install a non-existent package and see `yarn`
getting stuck due to an ongoing reporter activity. After the fix,
it shuts down properly.

Author: BYK

__tests__/reporters/__snapshots__/console-reporter.js.snap

@@ -145,3 +145,10 @@ exports[`Spinner 2`] = `"⠁ ⠂ foo"`;
 exports[`Spinner 3`] = `"⠁ ⠂ foo⠄ bar"`;
 
 exports[`Spinner 4`] = `"⠁ ⠂ foo⠄ bar"`;
+
+exports[`close 1`] = `
+Object {
+  "stderr": "░░ 0/2█░ 1/2⠁ ",
+  "stdout": "",
+}
+`;

__tests__/reporters/console-reporter.js

@@ -244,3 +244,23 @@ test('Spinner', () => {
   spinner.stop();
   expect(data).toMatchSnapshot();
 });
+
+test('close', async () => {
+  jest.useFakeTimers();
+  expect(
+    await getConsoleBuff(r => {
+      r.noProgress = false; // we need this to override is-ci when running tests on ci
+      const tick = r.progress(2);
+      tick();
+      jest.runAllTimers();
+      tick();
+
+      const activity = r.activity();
+      activity.tick('foo');
+
+      r.close();
+      // .close() should stop all timers and activities
+      jest.runAllTimers();
+    }),
+  ).toMatchSnapshot();
+});

src/reporters/console/console-reporter.js

@@ -1,6 +1,7 @@
 /* @flow */
 
 import type {
+  ReporterSetSpinner,
   ReporterSpinnerSet,
   Package,
   Trees,
@@ -37,12 +38,14 @@ export default class ConsoleReporter extends BaseReporter {
     super(opts);
 
     this._lastCategorySize = 0;
+    this._spinners = new Set();
     this.format = (chalk: any);
     this.isSilent = !!opts.isSilent;
   }
 
   _lastCategorySize: number;
   _progressBar: ?Progress;
+  _spinners: Set<Spinner>;
 
   _prependEmoji(msg: string, emoji: ?string): string {
     if (this.emoji && emoji && this.isTTY) {
@@ -65,6 +68,10 @@ export default class ConsoleReporter extends BaseReporter {
   }
 
   close() {
+    for (const spinner of this._spinners) {
+      spinner.stop();
+    }
+    this._spinners.clear();
     this.stopProgress();
     super.close();
   }
@@ -245,14 +252,16 @@ export default class ConsoleReporter extends BaseReporter {
       return super.activitySet(total, workers);
     }
 
-    const spinners = [];
+    const spinners: Array<ReporterSetSpinner> = [];
+    const reporterSpinners = this._spinners;
 
     for (let i = 1; i < workers; i++) {
       this.log('');
     }
 
     for (let i = 0; i < workers; i++) {
       const spinner = new Spinner(this.stderr, i);
+      reporterSpinners.add(spinner);
       spinner.start();
 
       let prefix: ?string = null;
@@ -287,6 +296,7 @@ export default class ConsoleReporter extends BaseReporter {
 
         end() {
           spinner.stop();
+          reporterSpinners.delete(spinner);
         },
       });
     }
@@ -309,17 +319,21 @@ export default class ConsoleReporter extends BaseReporter {
         end() {},
       };
     }
+    const reporterSpinners = this._spinners;
 
     const spinner = new Spinner(this.stderr);
     spinner.start();
 
+    reporterSpinners.add(spinner);
+
     return {
       tick(name: string) {
         spinner.setText(name);
       },
 
       end() {
         spinner.stop();
+        reporterSpinners.delete(spinner);
       },
     };
   }