test: adding tests for initHooks API

Async wrap providers tested:

- crypto.randomBytes
- crypto.pbkdf2
- fs event wrap
- fsreqwrap access
- fsreqwrap readFile
- getaddrinforeq wrap
- getnameinforeq wrap
- pipe connect wrap
- query wrap
- pipewrap
- processwrap
- shutdown wrap
- tcpwrap
- udpwrap
- send wrap
- detailed signal wrap
- statwatcher
- timerwrap via setTimeout
- timerwrap via setInterval
- for Immediate
- http parser request
- http parser response
- connection via ssl server
- tls wrap
- write wrap
- ttywrap via readstream
- ttywrap via wriream
- zctx via zlib binding deflate

Embedder API:

-  async-event tests
  - one test looks at the happy paths
  - another ensures that in cases of events emitted in an order that
  doesn't make sense, the order is enforced by async hooks throwing a
  meaningful error
  - embedder enforcement tests are split up since async hook stack
  corruption now the process
  - therefore we launch a child and check for error output of the offending code

Additional tests:

- tests that show that we can enable/disable hooks inside their lifetime
events
- tests that verify the graph of resources triggering the creation of
other resources

Test Helpers:

- init-hooks:
  - returns one collector instance
  - when created an async hook is created and the lifetime events are
  registered to call the appropriate collector functions
  - the collector also exposes `enable` and `disable` functions which call
  through to the async hook

- hook checks:
  - checks invocations of life time hooks against the actual invocations
  that were collected
  - in some cases like `destroy` a min/max range of invocations can be
  supplied since in these cases the exact number is non-deterministic

- verify graph:
  - verifies the triggerIds of specific async resources are as expected,
  i.e. the creation of resources was triggered by the resource we expect
  - includes a printGraph function to generate easily readable test
  input for verify graph
  - both functions prune TickObjects to create less brittle and easier
  to understand tests

PR-URL: nodejs#12892
Ref: nodejs#11883
Ref: nodejs#8531
Reviewed-By: Andreas Madsen <[email protected]>
Reviewed-By: Anna Henningsen <[email protected]>
Reviewed-By: Sam Roberts <[email protected]>
Reviewed-By: Matteo Collina <[email protected]>
Reviewed-By: Refael Ackermann <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Jeremiah Senkpiel <[email protected]>

Author: thlorenz

Diff for: test/async-hooks/coverage.md

@@ -0,0 +1,32 @@
+## AsyncHooks Coverage Overview
+
+Showing which kind of async resource is covered by which test:
+
+| Resource Type        | Test                                   |
+|----------------------|----------------------------------------|
+| CONNECTION           | test-connection.ssl.js                 |
+| FSEVENTWRAP          | test-fseventwrap.js                    |
+| FSREQWRAP            | test-fsreqwrap-{access,readFile}.js    |
+| GETADDRINFOREQWRAP   | test-getaddrinforeqwrap.js             |
+| GETNAMEINFOREQWRAP   | test-getnameinforeqwrap.js             |
+| HTTPPARSER           | test-httpparser.{request,response}.js  |
+| Immediate            | test-immediate.js                      |
+| JSSTREAM             | TODO (crashes when accessing directly) |
+| PBKDF2REQUEST        | test-crypto-pbkdf2.js                  |
+| PIPECONNECTWRAP      | test-pipeconnectwrap.js                |
+| PIPEWRAP             | test-pipewrap.js                       |
+| PROCESSWRAP          | test-pipewrap.js                       |
+| QUERYWRAP            | test-querywrap.js                      |
+| RANDOMBYTESREQUEST   | test-crypto-randomBytes.js             |
+| SHUTDOWNWRAP         | test-shutdownwrap.js                   |
+| SIGNALWRAP           | test-signalwrap.js                     |
+| STATWATCHER          | test-statwatcher.js                    |
+| TCPCONNECTWRAP       | test-tcpwrap.js                        |
+| TCPWRAP              | test-tcpwrap.js                        |
+| TIMERWRAP            | test-timerwrap.set{Timeout,Interval}.js|
+| TLSWRAP              | test-tlswrap.js                        |
+| TTYWRAP              | test-ttywrap.{read,write}stream.js     |
+| UDPSENDWRAP          | test-udpsendwrap.js                    |
+| UDPWRAP              | test-udpwrap.js                        |
+| WRITEWRAP            | test-writewrap.js                      |
+| ZLIB                 | test-zlib.zlib-binding.deflate.js      |

Diff for: test/async-hooks/hook-checks.js

@@ -0,0 +1,54 @@
+'use strict';
+const assert = require('assert');
+require('../common');
+
+/**
+ * Checks the expected invocations against the invocations that actually
+ * occurred.
+ *
+ * @name checkInvocations
+ * @function
+ * @param {Object} activity including timestamps for each life time event,
+ *                 i.e. init, before ...
+ * @param {Object} hooks the expected life time event invocations with a count
+ *                       indicating how oftn they should have been invoked,
+ *                       i.e. `{ init: 1, before: 2, after: 2 }`
+ * @param {String} stage the name of the stage in the test at which we are
+ *                       checking the invocations
+ */
+exports.checkInvocations = function checkInvocations(activity, hooks, stage) {
+  const stageInfo = `Checking invocations at stage "${stage}":\n   `;
+
+  assert.ok(activity != null,
+            `${stageInfo} Trying to check invocation for an activity, ` +
+            'but it was empty/undefined.'
+  );
+
+  // Check that actual invocations for all hooks match the expected invocations
+  [ 'init', 'before', 'after', 'destroy' ].forEach(checkHook);
+
+  function checkHook(k) {
+    const val = hooks[k];
+    // Not expected ... all good
+    if (val == null) return;
+
+    if (val === 0) {
+      // Didn't expect any invocations, but it was actually invoked
+      const invocations = activity[k].length;
+      const msg = `${stageInfo} Called "${k}" ${invocations} time(s), ` +
+                  'but expected no invocations.';
+      assert(activity[k] === null && activity[k] === undefined, msg);
+    } else {
+      // Expected some invocations, make sure that it was invoked at all
+      const msg1 = `${stageInfo} Never called "${k}", ` +
+                   `but expected ${val} invocation(s).`;
+      assert(activity[k] !== null && activity[k] !== undefined, msg1);
+
+      // Now make sure that the expected count and
+      // the actual invocation count match
+      const msg2 = `${stageInfo}  Called "${k}" ${activity[k].length} ` +
+                   `time(s), but expected ${val} invocation(s).`;
+      assert.strictEqual(activity[k].length, val, msg2);
+    }
+  }
+};