diff --git a/test/parallel/test-internal-module-map-asserts.js b/test/parallel/test-internal-module-map-asserts.js
new file mode 100644
index 00000000000000..7f7b980c9a91ab
--- /dev/null
+++ b/test/parallel/test-internal-module-map-asserts.js
@@ -0,0 +1,96 @@
+// Flags: --expose-internals
+'use strict';
+
+const common = require('../common');
+const assert = require('assert');
+const ModuleMap = require('internal/loader/ModuleMap');
+
+// ModuleMap.get, url argument should only accept string values
+{
+  const errorReg = common.expectsError({
+    code: 'ERR_INVALID_ARG_TYPE',
+    type: TypeError,
+    message: /^The "url" argument must be of type string/
+  }, 5);
+
+  const moduleMap = new ModuleMap();
+
+  assert.throws(() => moduleMap.get({}), errorReg);
+
+  assert.throws(() => moduleMap.get([]), errorReg);
+
+  assert.throws(() => moduleMap.get(true), errorReg);
+
+  assert.throws(() => moduleMap.get(1), errorReg);
+
+  assert.throws(() => moduleMap.get(() => {}), errorReg);
+}
+
+// ModuleMap.has, url argument should only accept string values
+{
+  const errorReg = common.expectsError({
+    code: 'ERR_INVALID_ARG_TYPE',
+    type: TypeError,
+    message: /^The "url" argument must be of type string/
+  }, 5);
+
+  const moduleMap = new ModuleMap();
+
+  assert.throws(() => moduleMap.has({}), errorReg);
+
+  assert.throws(() => moduleMap.has([]), errorReg);
+
+  assert.throws(() => moduleMap.has(true), errorReg);
+
+  assert.throws(() => moduleMap.has(1), errorReg);
+
+  assert.throws(() => moduleMap.has(() => {}), errorReg);
+}
+
+// ModuleMap.set, url argument should only accept string values
+{
+  const errorReg = common.expectsError({
+    code: 'ERR_INVALID_ARG_TYPE',
+    type: TypeError,
+    message: /^The "url" argument must be of type string/
+  }, 5);
+
+  // As long as the assertion of "job" argument is done after the assertion of
+  // "url" argument this test suite is ok.  Tried to mock the "job" parameter,
+  // but I think it's useless, and was not simple to mock...
+  const job = undefined;
+
+  const moduleMap = new ModuleMap();
+
+  assert.throws(() => moduleMap.set({}, job), errorReg);
+
+  assert.throws(() => moduleMap.set([], job), errorReg);
+
+  assert.throws(() => moduleMap.set(true, job), errorReg);
+
+  assert.throws(() => moduleMap.set(1, job), errorReg);
+
+  assert.throws(() => moduleMap.set(() => {}, job), errorReg);
+}
+
+
+// ModuleMap.set, job argument should only accept ModuleJob values
+{
+  const errorReg = common.expectsError({
+    code: 'ERR_INVALID_ARG_TYPE',
+    type: TypeError,
+    message: /^The "job" argument must be of type ModuleJob/
+  }, 5);
+
+  const moduleMap = new ModuleMap();
+
+  assert.throws(() => moduleMap.set('', {}), errorReg);
+
+  assert.throws(() => moduleMap.set('', []), errorReg);
+
+  assert.throws(() => moduleMap.set('', true), errorReg);
+
+  assert.throws(() => moduleMap.set('', 1), errorReg);
+
+  assert.throws(() => moduleMap.set('', () => {}), errorReg);
+}
diff --git a/test/parallel/test-whatwg-url-searchparams-sort.js b/test/parallel/test-whatwg-url-searchparams-sort.js
index 0e01c627eea6e4..1122f08dcc0434 100644
--- a/test/parallel/test-whatwg-url-searchparams-sort.js
+++ b/test/parallel/test-whatwg-url-searchparams-sort.js
@@ -40,10 +40,10 @@ const { test, assert_equals, assert_array_equals } = require('../common/wpt');
       assert_array_equals(param, val.output[i])
       i++
     }
-  }, "Parse and sort: " + val.input)
+  }, `Parse and sort: ${val.input}`)
 
   test(() => {
-    let url = new URL("?" + val.input, "https://example/")
+    let url = new URL(`?${val.input}`, "https://example/")
     url.searchParams.sort()
     let params = new URLSearchParams(url.search),
         i = 0
@@ -51,7 +51,7 @@ const { test, assert_equals, assert_array_equals } = require('../common/wpt');
       assert_array_equals(param, val.output[i])
       i++
     }
-  }, "URL parse and sort: " + val.input)
+  }, `URL parse and sort: ${val.input}`)
 })
 
 test(function() {
@@ -90,7 +90,7 @@ tests.forEach((val) => {
       assert_array_equals(param, val.output[i]);
       i++;
     }
-  }, 'Parse and sort: ' + val.input);
+  }, `Parse and sort: ${val.input}`);
 
   test(() => {
     const url = new URL(`?${val.input}`, 'https://example/');
@@ -101,5 +101,5 @@ tests.forEach((val) => {
       assert_array_equals(param, val.output[i]);
       i++;
     }
-  }, 'URL parse and sort: ' + val.input);
+  }, `URL parse and sort: ${val.input}`);
 });