fix: ensurances for falsey values

Signed-off-by: Charlike Mike Reagent <mameto2011@gmail.com>

Author: Charlike Mike Reagent

package.json

@@ -7,6 +7,7 @@
     "docs": "docks --outfile .verb.md && verb",
     "lint": "eslint '**/*.js' --cache --fix --quiet --format codeframe",
     "test": "nyc asia",
+    "test-only": "asia -r esm -u",
     "commit": "yarn lint && yarn test && yarn dry",
     "dry": "git add -A && git status --porcelain && gitcommit -sS",
     "release": "tunnckocore-release",

src/main.js

@@ -211,7 +211,7 @@ export function validate(commits, ret = false) {
 export function check(commits, flat) {
   const result = []
     .concat(commits)
-    .filter(Boolean)
+    .filter((x) => x !== null || x !== undefined)
     .reduce((acc, commit) => {
       if (typeof commit === 'string') {
         commit = parseCommit(commit); // eslint-disable-line no-param-reassign

test/commit/snapshots/check.test.snapshot.json

@@ -45,3 +45,18 @@ test('should check(object|array) return array even with flat=true, if more than
     footer: null,
   });
 });
+
+test("should check('') fail when empty string given", (t) => {
+  t.throws(() => check(''), TypeError);
+  t.throws(() => check(''), /expect `commit` to be non empty string/);
+});
+test('should check fail on false values, correctly', (t) => {
+  t.throws(() => check(), TypeError);
+  t.throws(() => check(), /expect `commit` to be an object/);
+
+  t.throws(() => check(undefined), TypeError);
+  t.throws(() => check(undefined), /expect `commit` to be an object/);
+
+  t.throws(() => check(null), TypeError);
+  t.throws(() => check(null), /expect `commit` to be an object/);
+});