fix: recognize windows drive letters with a leading slash, like '/C:/' (

#21)

* fix: normalize '/C:/' to lowercase since we do that for 'C:/'

* two more tests

src/__tests__/normalize.spec.ts

@@ -10,6 +10,18 @@ describe('normalize', () => {
     });
   });
 
+  describe('normalizes capitalization of Windows drive letters', () => {
+    it.each`
+      path                    | result
+      ${'C:\\foo\\bar'}       | ${'c:/foo/bar'}
+      ${'/C:/foo/bar'}        | ${'c:/foo/bar'}
+      ${'file:///C:/foo/bar'} | ${'c:/foo/bar'}
+      ${'file://C:/foo/bar'}  | ${'c:/foo/bar'}
+    `("normalize('$path')", ({ path, result }) => {
+      expect(normalize(path)).toEqual(result);
+    });
+  });
+
   describe('ignores POSIX slashes', () => {
     it.each`
       path        | result

src/__tests__/startsWithWindowsDrive.spec.ts

@@ -1,7 +1,7 @@
 import { startsWithWindowsDrive } from '../';
 
 describe('startsWithWindowsDrive', () => {
-  it.each(['c:\\foo\\bar.json', 'c:\\', 'c:/', 'c:/foo/bar.json', 'c:\\', 'Z:\\', 'A:/'])(
+  it.each(['c:\\foo\\bar.json', 'c:\\', 'c:/', 'c:/', '/C:/', '/C:\\', 'c:/foo/bar.json', 'c:\\', 'Z:\\', 'A:/'])(
     'recognizes driver letter in %s',
     filepath => {
       expect(startsWithWindowsDrive(filepath)).toBe(true);

src/grammar.pegjs

@@ -75,20 +75,20 @@ AbsolutePath
 }
 
   Root
-    = PosixRoot
-    / WindowsRoot
+    = WindowsRoot
+    / PosixRoot
 
-    PosixRoot
-      = Sep {
+    WindowsRoot
+      = Sep ? drive:[A-Za-z] ":" Sep {
         return {
-          drive: null
+          drive: drive.toLowerCase() + ':'
         }
       }
 
-    WindowsRoot
-      = drive:[A-Za-z] ":" Sep {
+    PosixRoot
+      = Sep {
         return {
-          drive: drive.toLowerCase() + ':'
+          drive: null
         }
       }