Remove warnings for literal words

Why:

*   Sometimes, words are meant literally and without their original
    definition. For example, `Dont use “he”.`

How:

*   Add `nlcst-is-literal` as a dependency, which checks whether
    a word is surrounded by quotes, parens, brackets, commans, colons
    and whatnot.

component.json

@@ -23,7 +23,8 @@
     "wooorm/nlcst-to-string": "^1.0.0",
     "ljharb/object-keys": "^1.0.7",
     "blakeembrey/pluralize": "^1.1.4",
-    "wooorm/unist-util-visit": "^1.0.0"
+    "wooorm/unist-util-visit": "^1.0.0",
+    "wooorm/nlcst-is-literal": "^1.0.0"
   },
   "repository": "wooorm/retext-equality",
   "scripts": [

lib/equality.js

@@ -16,6 +16,7 @@
 var keys = require('object-keys');
 var visit = require('unist-util-visit');
 var nlcstToString = require('nlcst-to-string');
+var isLiteral = require('nlcst-is-literal');
 var patterns = require('./patterns.json');
 
 /*
@@ -506,11 +507,19 @@ function factory(file) {
          */
 
         visit(node, 'WordNode', function (child, position, parent) {
-            var patterns = byWord[toString(child).toLowerCase()];
-            var length = patterns ? patterns.length : 0;
-            var index = -1;
+            var patterns;
+            var length;
+            var index;
             var result;
 
+            if (isLiteral(parent, position)) {
+                return;
+            }
+
+            patterns = byWord[toString(child).toLowerCase()];
+            length = patterns ? patterns.length : 0;
+            index = -1;
+
             while (++index < length) {
                 result = test(file, byId[patterns[index]], position, parent);
 

package.json

@@ -20,6 +20,7 @@
     "retext"
   ],
   "dependencies": {
+    "nlcst-is-literal": "^1.0.0",
     "nlcst-to-string": "^1.0.0",
     "object-keys": "^1.0.7",
     "pluralize": "^1.1.4",