TypeError: s.toLowerCase is not a function (#2997)

* Update color.js

* fixup

* expand test

* expand test (again)

gh-badges/lib/color.js

@@ -34,7 +34,7 @@ Object.entries(aliases).forEach(([alias, original]) => {
 // true.
 const hexColorRegex = /^([\da-f]{3}){1,2}$/i
 function isHexColor(s = '') {
-  return hexColorRegex.test(s.toLowerCase())
+  return hexColorRegex.test(s)
 }
 
 function normalizeColor(color) {

gh-badges/lib/color.spec.js

@@ -5,7 +5,16 @@ const { isHexColor, normalizeColor, toSvgColor } = require('./color')
 
 test(isHexColor, () => {
   forCases([given('f00bae'), given('4c1'), given('ABC123')]).expect(true)
-  forCases([given('f00bar'), given(''), given(undefined)]).expect(false)
+  forCases([
+    given('f00bar'),
+    given(''),
+    given(undefined),
+    given(null),
+    given(true),
+    given([]),
+    given({}),
+    given(() => {}),
+  ]).expect(false)
 })
 
 test(normalizeColor, () => {
@@ -17,9 +26,16 @@ test(normalizeColor, () => {
   given('#ABC123').expect('#abc123')
   given('papayawhip').expect('papayawhip')
   given('purple').expect('purple')
-  forCases([given(''), given(undefined), given('not-a-color')]).expect(
+  forCases([
-    undefined
+    given(''),
-  )
+    given('not-a-color'),
+    given(undefined),
+    given(null),
+    given(true),
+    given([]),
+    given({}),
+    given(() => {}),
+  ]).expect(undefined)
   given('lightgray').expect('lightgrey')
   given('informational').expect('blue')
 })