test(NODE-3236): separate unit from functional (#2991)

Author: dariakp

.evergreen/run-checks.sh

@@ -14,3 +14,5 @@ echo "Typescript $(npx tsc -v)"
 npx tsc --noEmit mongodb.ts34.d.ts
 # check that resolution uses the downleveled types
 echo "import * as mdb from '.'" > file.ts && npx tsc --noEmit --traceResolution file.ts | grep 'mongodb.ts34.d.ts' && rm file.ts
+
+npm run check:unit

.mocharc.json

@@ -6,9 +6,9 @@
   ],
   "require": [
     "ts-node/register",
-    "source-map-support/register"
+    "source-map-support/register",
+    "test/tools/runner/chai-addons.js"
   ],
-  "file": "test/tools/runner",
   "ui": "test/tools/runner/metadata_ui.js",
   "recursive": true,
   "timeout": 60000,

package.json

@@ -100,23 +100,25 @@
     "build:dts": "npm run build:ts && api-extractor run && rimraf 'lib/**/*.d.ts*' && downlevel-dts mongodb.d.ts mongodb.ts34.d.ts",
     "build:docs": "typedoc",
     "check:bench": "node test/benchmarks/driverBench",
-    "check:coverage": "nyc npm run check:test",
+    "check:coverage": "nyc npm run test:all",
     "check:lint": "npm run build:dts && npm run check:dts && npm run check:eslint && npm run check:tsd",
     "check:eslint": "eslint -v && eslint --max-warnings=0 --ext '.js,.ts' src test",
     "check:tsd": "tsd --version && tsd",
     "check:dts": "tsc --noEmit mongodb.d.ts && tsd",
-    "check:test": "mocha --recursive test/functional test/unit",
+    "check:test": "mocha --file test/tools/runner --recursive test/functional",
+    "check:unit": "mocha --recursive test/unit/",
     "check:ts": "tsc -v && tsc --noEmit",
     "check:atlas": "mocha --config \"test/manual/mocharc.json\" test/manual/atlas_connectivity.test.js",
-    "check:adl": "mocha test/manual/data_lake.test.js",
+    "check:adl": "mocha --file test/tools/runner test/manual/data_lake.test.js",
     "check:ocsp": "mocha --config \"test/manual/mocharc.json\" test/manual/ocsp_support.test.js",
     "check:kerberos": "mocha --config \"test/manual/mocharc.json\" test/manual/kerberos.test.js",
     "check:tls": "mocha --config \"test/manual/mocharc.json\" test/manual/tls_support.test.js",
     "check:ldap": "mocha --config \"test/manual/mocharc.json\" test/manual/ldap.test.js",
     "check:csfle": "mocha test/functional/client_side_encryption",
     "prepare": "node etc/prepare.js",
     "release": "standard-version -i HISTORY.md",
-    "test": "npm run check:lint && npm run check:test"
+    "test": "npm run check:lint && npm run test:all",
+    "test:all": "npm run check:unit && npm run check:test"
   },
   "tsd": {
     "directory": "test/types",