From eba1e53706b24d95e9257a23cbebb9abb6818031 Mon Sep 17 00:00:00 2001
From: Matthieu Felix <matthieufelix@gmail.com>
Date: Tue, 14 Nov 2017 18:57:33 -0500
Subject: [PATCH] Add TOC depth option

---
 lib/markdown2.py                 |  6 ++++++
 test/tm-cases/toc_depth.html     | 19 +++++++++++++++++++
 test/tm-cases/toc_depth.opts     |  5 +++++
 test/tm-cases/toc_depth.tags     |  1 +
 test/tm-cases/toc_depth.text     | 20 ++++++++++++++++++++
 test/tm-cases/toc_depth.toc_html | 13 +++++++++++++
 6 files changed, 64 insertions(+)
 create mode 100644 test/tm-cases/toc_depth.html
 create mode 100644 test/tm-cases/toc_depth.opts
 create mode 100644 test/tm-cases/toc_depth.tags
 create mode 100644 test/tm-cases/toc_depth.text
 create mode 100644 test/tm-cases/toc_depth.toc_html

diff --git a/lib/markdown2.py b/lib/markdown2.py
index 84d7d6c2..1998c140 100755
--- a/lib/markdown2.py
+++ b/lib/markdown2.py
@@ -243,6 +243,10 @@ def __init__(self, html4tags=False, tab_width=4, safe_mode=None,
         assert isinstance(self.extras, dict)
         if "toc" in self.extras and "header-ids" not in self.extras:
             self.extras["header-ids"] = None   # "toc" implies "header-ids"
+            if self.extras["toc"] is None:
+                self._toc_depth = 6
+            else:
+                self._toc_depth = self.extras["toc"].get("depth", 6)
         self._instance_extras = self.extras.copy()
 
         self.link_patterns = link_patterns
@@ -1500,6 +1504,8 @@ def header_id_from_text(self, text, prefix, n):
 
     _toc = None
     def _toc_add_entry(self, level, id, name):
+        if level > self._toc_depth:
+            return
         if self._toc is None:
             self._toc = []
         self._toc.append((level, id, self._unescape_special_chars(name)))
diff --git a/test/tm-cases/toc_depth.html b/test/tm-cases/toc_depth.html
new file mode 100644
index 00000000..9b02121a
--- /dev/null
+++ b/test/tm-cases/toc_depth.html
@@ -0,0 +1,19 @@
+<h1 id="readme-for-blah">README for Blah</h1>
+
+<h2 id="introduction">Introduction</h2>
+
+<h2 id="the-meat">The Meat</h2>
+
+<h3 id="beef">Beef</h3>
+
+<h5 id="steak">Steak</h5>
+
+<h5 id="burgers">Burgers</h5>
+
+<h3 id="chicken">Chicken</h3>
+
+<h3 id="pork">Pork</h3>
+
+<h4 id="mmmmmmmm-bacon">Mmmmmmmm, bacon</h4>
+
+<h1 id="at-the-top-level-again">At the <em>top</em> level again!?</h1>
diff --git a/test/tm-cases/toc_depth.opts b/test/tm-cases/toc_depth.opts
new file mode 100644
index 00000000..4494a0ac
--- /dev/null
+++ b/test/tm-cases/toc_depth.opts
@@ -0,0 +1,5 @@
+{
+  "extras": {
+    "toc": {"depth": 3}
+  }
+}
diff --git a/test/tm-cases/toc_depth.tags b/test/tm-cases/toc_depth.tags
new file mode 100644
index 00000000..2b2472e0
--- /dev/null
+++ b/test/tm-cases/toc_depth.tags
@@ -0,0 +1 @@
+toc extra
diff --git a/test/tm-cases/toc_depth.text b/test/tm-cases/toc_depth.text
new file mode 100644
index 00000000..34f629a6
--- /dev/null
+++ b/test/tm-cases/toc_depth.text
@@ -0,0 +1,20 @@
+# README for Blah
+
+## Introduction
+
+## The Meat
+
+### Beef
+
+##### Steak
+
+##### Burgers
+
+### Chicken
+
+### Pork
+
+#### Mmmmmmmm, bacon
+
+# At the *top* level again!?
+
diff --git a/test/tm-cases/toc_depth.toc_html b/test/tm-cases/toc_depth.toc_html
new file mode 100644
index 00000000..3696712a
--- /dev/null
+++ b/test/tm-cases/toc_depth.toc_html
@@ -0,0 +1,13 @@
+<ul>
+  <li><a href="#readme-for-blah">README for Blah</a>
+  <ul>
+    <li><a href="#introduction">Introduction</a></li>
+    <li><a href="#the-meat">The Meat</a>
+    <ul>
+      <li><a href="#beef">Beef</a></li>
+      <li><a href="#chicken">Chicken</a></li>
+      <li><a href="#pork">Pork</a></li>
+    </ul></li>
+  </ul></li>
+  <li><a href="#at-the-top-level-again">At the <em>top</em> level again!?</a></li>
+</ul>