Include file/string name in params object for custom rules (fixes #119).

lib/markdownlint.js

@@ -283,7 +283,7 @@ function uniqueFilterForSortedErrors(value, index, array) {
 
 // Lints a single string
 function lintContent(
-  ruleList, content, config, frontMatter, noInlineConfig, resultVersion,
+  ruleList, name, content, config, frontMatter, noInlineConfig, resultVersion,
   callback) {
   // Remove UTF-8 byte order marker (if present)
   content = content.replace(/^\ufeff/, "");
@@ -304,9 +304,10 @@ function lintContent(
     effectiveConfig, aliasToRuleNames);
   // Create parameters for rules
   const params = {
-    "tokens": tokens,
-    "lines": lines,
-    "frontMatterLines": frontMatterLines
+    name,
+    tokens,
+    lines,
+    frontMatterLines
   };
   shared.makeTokenCache(params);
   // Function to run for each rule
@@ -411,7 +412,7 @@ function lintFile(
     if (err) {
       return callback(err);
     }
-    lintContent(ruleList, content, config, frontMatter, noInlineConfig,
+    lintContent(ruleList, file, content, config, frontMatter, noInlineConfig,
       resultVersion, callback);
   }
   // Make a/synchronous call to read file
@@ -465,6 +466,7 @@ function lintInput(options, synchronous, callback) {
       if ((item = stringsKeys.shift())) {
         lintContent(
           ruleList,
+          item,
           strings[item] || "",
           config,
           frontMatter,