(bug)[Generic Lexer]: Make Generic Lexer Case Insensitive

- add token transformation to make generic lexer case insensitive

Fixes #7

Author: mahirshah

src/constants/genericLexer.js

@@ -1,12 +1,24 @@
 const moo = require('moo');
 
 module.exports = moo.compile({
-  color: /(?:#(?:[0-9a-fA-F]{2}){2,4}|#[0-9a-fA-F]{3}|(?:rgba?|hsla?)\(\s*(?:\d+%?(?:deg|rad|grad|turn)?(?:,|\s)+){2,3}[\s/]*[\d.]+%?\s*\))/,
+  color: {
+    match: /(?:#(?:[0-9a-fA-F]{2}){2,4}|#[0-9a-fA-F]{3}|(?:rgba?|hsla?)\(\s*(?:\d+%?(?:deg|rad|grad|turn)?(?:,|\s)+){2,3}[\s/]*[\d.]+%?\s*\))/,
+    value: match => match.toLowerCase(),
+  },
   number: /(?:[+-])?(?:(?:\d+\.\d*)|(?:\d*\.\d+))/,
   integer: /(?:[+-])?[0-9]+/,
   string: /(?:"[^"]")|(?:'[^']')/,
   functionStart: /[a-zA-Z]+\(/,
-  customIdent: /[^0-9\s](?:[a-zA-Z0-9_-]|(?:\\.))*/,
-  ident: /[a-zA-Z-]+/,
-  char: /./,
+  customIdent: {
+    match: /[^0-9\s](?:[a-zA-Z0-9_-]|(?:\\.))*/,
+    value: match => match.toLowerCase(),
+  },
+  ident: {
+    match: /[a-zA-Z-]+/,
+    value: match => match.toLowerCase(),
+  },
+  char: {
+    match: /./,
+    value: match => match.toLowerCase(),
+  },
 });

test/isValidDeclarationTest.js

@@ -19,7 +19,7 @@ describe('isValidDeclaration', function () {
   });
 
   describe('border', function () {
-    ['1px', 'solid', 'black', '1px solid', 'solid 1px', '1px solid black', 'medium dashed green', 'green medium dashed']
+    ['1px', 'solid', 'black', 'Black', 'bLaCk', '1px solid', 'solid 1px', '1px solid black', 'medium dashed green', 'gReeN mEdiuM DasHed', 'green medium dashed']
       .forEach((value) => {
         it(`should return true for ${value}`, function () {
           assert(isValidDeclaration('border', value));
@@ -28,7 +28,7 @@ describe('isValidDeclaration', function () {
   });
 
   describe('margin', function () {
-    ['0', 'auto', '1px', '1em', '0 auto', '1px 1px', '1px 1em', '20% auto 1px', '20% 1px 20em -2%', 'var(--hello09-a)']
+    ['0', 'auto', '1px', '1em', '0 auto', '1px 1px', '1px 1em', '20% auto 1px', '20% 1px 20em -2%', 'var(--hello09-a)', '1Px', '2PX', '0 aUto']
       .forEach((value) => {
         it(`should return true for ${value}`, function () {
           assert(isValidDeclaration('margin', value));