Update MD041/first-line-h1 to ignore leading HTML comments (fixes #37).

doc/Rules.md

@@ -1037,17 +1037,13 @@ Parameters: level (number; default 1)
 This rule is triggered when the first line in the file isn't a top level (h1)
 header:
 
-    ```
     This is a file without a header
-    ```
 
 To fix this, add a header to the top of your file:
 
-    ```
     # File with header
 
     This is a file with a top level header
-    ```
 
 Note: The `level` parameter can be used to change the top level (ex: to h2) in
 cases where an h1 is added externally.

lib/rules.js

@@ -1019,21 +1019,19 @@ module.exports = [
     "func": function MD041(params, errors) {
       var level = params.options.level || 1;
       var tag = "h" + level;
-      var firstHeader = null;
-      params.tokens.every(function forToken(token) {
+      params.tokens.every(function forToken(token, index) {
         if (token.type === "heading_open") {
-          firstHeader = token;
-          return false;
-        } else if (token.lineNumber > 1) {
-          return false;
+          if (!((token.lineNumber === 1) || (index > 0)) ||
+              (token.tag !== tag)) {
+            errors.addContext(token.lineNumber, token.line);
           }
+          return false;
+        } else if (token.type === "html_block") {
           return true;
-      });
-      if (!firstHeader ||
-          (firstHeader.lineNumber !== 1) ||
-          (firstHeader.tag !== tag)) {
-        errors.addContext(1, params.lines[0]);
         }
+        errors.addContext(token.lineNumber, token.line);
+        return false;
+      });
     }
   },
 

test/md041-ignore-leading-comments-combined.json

@@ -0,0 +1,4 @@
+{
+  "default": true,
+  "first-line-h1": true
+}

test/md041-ignore-leading-comments-combined.md

@@ -0,0 +1,11 @@
+# Heading # <!-- markdownlint-disable no-hard-tabs -->
+
+Text text text
+
+Embedded	tab
+
+Text text text
+
+Trailing space {MD009}     
+
+Text text text

test/md041-ignore-leading-comments-violation.json

@@ -0,0 +1,4 @@
+{
+  "default": true,
+  "first-line-h1": true
+}

test/md041-ignore-leading-comments-violation.md

@@ -0,0 +1,11 @@
+<!-- markdownlint-disable no-hard-tabs -->
+
+Text text text {MD041}
+
+Embedded	tab
+
+Text text text
+
+Trailing space {MD009}     
+
+Text text text

test/md041-ignore-leading-comments.json

@@ -0,0 +1,4 @@
+{
+  "default": true,
+  "first-line-h1": true
+}

test/md041-ignore-leading-comments.md

@@ -0,0 +1,13 @@
+<!-- markdownlint-disable no-hard-tabs -->
+
+# Heading
+
+Text text text
+
+Embedded	tab
+
+Text text text
+
+Trailing space {MD009}     
+
+Text text text