Add parametrized test-cases.

Author: vbabanin

source/mongodb-handshake/tests/README.md

@@ -94,6 +94,11 @@ for verification purposes.
 Drivers should verify that metadata provided after `MongoClient` initialization is appended, not replaced, and is
 visible in the `hello` command of new connections.
 
+There are multiple test cases parameterized with `DriverInfoOptions` to be appended after `MongoClient` initialization.
+Before each test case, perform the setup.
+
+#### Setup
+
 1. Create a `MongoClient` instance with the following:
 
     - `maxIdleTimeMS` set to `1ms`
@@ -114,33 +119,67 @@ visible in the `hello` command of new connections.
 
 3. Wait 5ms for the connection to become idle.
 
-4. Append the following `DriverInfoOptions` to the `MongoClient` metadata:
+#### Parameterized test cases
 
-    | Field    | Value              |
-    | -------- | ------------------ |
-    | name     | framework          |
-    | version  | 2.0                |
-    | platform | Framework Platform |
+**Case 1**
+
+| Field    | Value              |
+| -------- | ------------------ |
+| name     | framework          |
+| version  | 2.0                |
+| platform | Framework Platform |
+
+**Case 2**
 
-5. Send `ping` command to the server and verify:
+| Field    | Value     |
+| -------- | --------- |
+| name     | framework |
+| version  | 2.0       |
+| platform | null      |
+
+**Case 3**
+
+| Field    | Value              |
+| -------- | ------------------ |
+| name     | framework          |
+| version  | null               |
+| platform | Framework Platform |
+
+**Case 4**
+
+| Field    | Value     |
+| -------- | --------- |
+| name     | framework |
+| version  | null      |
+| platform | null      |
+
+#### Running a test case
+
+1. Append the `DriverInfoOptions` from the selected test case to the `MongoClient` metadata.
+
+2. Send a `ping` command to the server and verify:
 
     - The command succeeds.
 
     - The framework metadata is appended to the existing `DriverInfoOptions` in the `client.driver` fields of the `hello`
-        command.
+        command, with values separated by a pipe `|`.
 
-        | Field    | Value                                |
-        | -------- | ------------------------------------ |
-        | name     | library\|framework                   |
-        | version  | 1.2\|2.0                             |
-        | platform | Library Platform\|Framework Platform |
+        - `client.driver.name`:
+            - If test case's name is non-null: `library|<name>`
+            - Otherwise, the field remains unchanged: `library`
+        - `client.driver.version`:
+            - If test case's version is non-null: `1.2|<version>`
+            - Otherwise, the field remains unchanged: `1.2`
+        - `client.driver.platform`:
+            - If test case's platform is non-null: `Library Platform|<platform>`
+            - Otherwise, the field remains unchanged: `Library Platform`
 
-    - All other subfields in the client document remain unchanged from `initialClientMetadata`.
+    - All other subfields in the `client` document remain unchanged from `initialClientMetadata`.
 
 ### Test 2: Test that metadata is not updated on established connections
 
 Drivers should verify that appending metadata after `MongoClient` initialization does **not** close existing
-connections, and that no new `hello` command is sent.
+connections, and that no new `hello` command is sent on existing connections.
 
 1. Create a `MongoClient` instance with wrapping library metadata:
 
@@ -163,7 +202,7 @@ connections, and that no new `hello` command is sent.
     | version  | 2.0                |
     | platform | Framework Platform |
 
-4. Send another `ping` command to the server and verify:
+4. Send a `ping` command to the server and verify:
 
     - The command succeeds.
     - No `hello` command is sent.