From acd36d5802a79b99525da2d7d3b10e8dc7ad9792 Mon Sep 17 00:00:00 2001
From: David Anson <david@dlaa.me>
Date: Thu, 23 Feb 2017 22:08:54 -0800
Subject: [PATCH] Update MD041/first-line-h1 to ignore leading HTML comments
 (fixes #37).

---
 doc/Rules.md                                  |  4 ----
 lib/rules.js                                  | 20 +++++++++----------
 ...d041-ignore-leading-comments-combined.json |  4 ++++
 .../md041-ignore-leading-comments-combined.md | 11 ++++++++++
 ...041-ignore-leading-comments-violation.json |  4 ++++
 ...md041-ignore-leading-comments-violation.md | 11 ++++++++++
 test/md041-ignore-leading-comments.json       |  4 ++++
 test/md041-ignore-leading-comments.md         | 13 ++++++++++++
 8 files changed, 56 insertions(+), 15 deletions(-)
 create mode 100644 test/md041-ignore-leading-comments-combined.json
 create mode 100644 test/md041-ignore-leading-comments-combined.md
 create mode 100644 test/md041-ignore-leading-comments-violation.json
 create mode 100644 test/md041-ignore-leading-comments-violation.md
 create mode 100644 test/md041-ignore-leading-comments.json
 create mode 100644 test/md041-ignore-leading-comments.md

diff --git a/doc/Rules.md b/doc/Rules.md
index abb1db06..201606e1 100644
--- a/doc/Rules.md
+++ b/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.
diff --git a/lib/rules.js b/lib/rules.js
index 7059308c..053daf8b 100644
--- a/lib/rules.js
+++ b/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) {
+          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;
         }
-        return true;
+        errors.addContext(token.lineNumber, token.line);
+        return false;
       });
-      if (!firstHeader ||
-          (firstHeader.lineNumber !== 1) ||
-          (firstHeader.tag !== tag)) {
-        errors.addContext(1, params.lines[0]);
-      }
     }
   },
 
diff --git a/test/md041-ignore-leading-comments-combined.json b/test/md041-ignore-leading-comments-combined.json
new file mode 100644
index 00000000..2be9298b
--- /dev/null
+++ b/test/md041-ignore-leading-comments-combined.json
@@ -0,0 +1,4 @@
+{
+  "default": true,
+  "first-line-h1": true
+}
diff --git a/test/md041-ignore-leading-comments-combined.md b/test/md041-ignore-leading-comments-combined.md
new file mode 100644
index 00000000..e3dc0814
--- /dev/null
+++ b/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
diff --git a/test/md041-ignore-leading-comments-violation.json b/test/md041-ignore-leading-comments-violation.json
new file mode 100644
index 00000000..2be9298b
--- /dev/null
+++ b/test/md041-ignore-leading-comments-violation.json
@@ -0,0 +1,4 @@
+{
+  "default": true,
+  "first-line-h1": true
+}
diff --git a/test/md041-ignore-leading-comments-violation.md b/test/md041-ignore-leading-comments-violation.md
new file mode 100644
index 00000000..58ca7025
--- /dev/null
+++ b/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
diff --git a/test/md041-ignore-leading-comments.json b/test/md041-ignore-leading-comments.json
new file mode 100644
index 00000000..2be9298b
--- /dev/null
+++ b/test/md041-ignore-leading-comments.json
@@ -0,0 +1,4 @@
+{
+  "default": true,
+  "first-line-h1": true
+}
diff --git a/test/md041-ignore-leading-comments.md b/test/md041-ignore-leading-comments.md
new file mode 100644
index 00000000..3c61047d
--- /dev/null
+++ b/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