test(path): add additional tests to normalize (#5036)

add additional tests to stencil's wrapped version of `path.normalize`,
adding additional documentation to how the wrapped function works.
specifically, add tests to verify the following behavior:
1. how an empty string behaves
2. how relative paths ('.', '..') behave
3. how absolute paths ('/' for POSIX and '\\' for Windows) behave

questioning how thise function behaves/should behave was the impetus
for this change - I didn't understand what I was seeing at first when
debugging some Stencil 4.x related path related bugs. this commit is
spun out from that work.

related to: #5029, #5032

src/utils/path.ts

@@ -249,6 +249,10 @@ export function join(...paths: string[]): string {
  * @returns a resolved path!
  */
 export function resolve(...paths: string[]): string {
+  /**
+   * When normalizing, we should _not_ attempt to relativize the path returned by the native Node `resolve` method. When
+   * calculating the path from each of the string-based parts, Node does not prepend './' to the calculated path.
+   */
   return normalizePath(path.resolve(...paths), false);
 }
 
@@ -263,5 +267,9 @@ export function resolve(...paths: string[]): string {
  * @returns a normalized path!
  */
 export function normalize(toNormalize: string): string {
+  /**
+   * When normalizing, we should _not_ attempt to relativize the path returned by the native Node `normalize` method.
+   * When calculating the path from each of the string-based parts, Node does not prepend './' to the calculated path.
+   */
   return normalizePath(path.normalize(toNormalize), false);
 }

src/utils/test/path.spec.ts

@@ -164,6 +164,11 @@ describe('normalizeFsPathQuery', () => {
     });
 
     it('normalize should always return a POSIX path', () => {
+      expect(normalize('')).toBe('.');
+      expect(normalize('.')).toBe('.');
+      expect(normalize('..')).toBe('..');
+      expect(normalize('/')).toBe('/');
+      expect(normalize('\\')).toBe('/');
       // these examples taken from
       // https://nodejs.org/api/path.html#pathnormalizepath
       expect(normalize('\\temp\\\\foo\\bar\\..\\')).toBe('/temp/foo');