From 5d1987759078e3eb4d89031ac452550e9af6ecd6 Mon Sep 17 00:00:00 2001
From: Estevao Soares dos Santos <estevao.santos@gmail.com>
Date: Sat, 17 Dec 2016 06:01:15 +0000
Subject: [PATCH] feat(requireSpaceBeforeHeadingText): option to make space
 between `#` and header text mandatory

Credit: @nikz [Nik Wakelin](https://github.com/nikz)

Closes #277
---
 README.md                                     |   2 ++
 dist/showdown.js                              | Bin 72395 -> 72745 bytes
 dist/showdown.js.map                          | Bin 213487 -> 214375 bytes
 dist/showdown.min.js                          | Bin 29334 -> 29595 bytes
 dist/showdown.min.js.map                      | Bin 32594 -> 32736 bytes
 src/options.js                                |   5 +++++
 src/showdown.js                               |   3 ++-
 src/subParsers/headers.js                     |   4 +++-
 .../requireSpaceBeforeHeadingText.html        |   2 ++
 .../features/requireSpaceBeforeHeadingText.md |   3 +++
 test/node/testsuite.features.js               |   2 ++
 11 files changed, 19 insertions(+), 2 deletions(-)
 create mode 100644 test/features/requireSpaceBeforeHeadingText.html
 create mode 100644 test/features/requireSpaceBeforeHeadingText.md

diff --git a/README.md b/README.md
index d7730c3..edb19e5 100644
--- a/README.md
+++ b/README.md
@@ -288,6 +288,8 @@ var defaultOptions = showdown.getDefaultOptions();
    wrapped in two</p>
    ```
 
+ * **requireSpaceBeforeHeadingText**: (boolean) [default false] Makes adding a space between `#` and the header text mandatory (since v1.5.3)
+ 
 ## Flavors
 
 You can also use flavors or presets to set the correct options automatically, so that showdown behaves like popular markdown flavors.
diff --git a/dist/showdown.js b/dist/showdown.js
index 61b604df1beb05c45eba8003c3464aa8f6c42ae6..2c6fbe172be3a46a154e2931945b168f34e55076 100644
GIT binary patch
delta 277
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delta 36
ucmV+<0NekmxCG0!1h6m)v+fE?1hZ@pu(gv^f)<l~#UYafi5j!n#ZXo!R1gLL

diff --git a/dist/showdown.js.map b/dist/showdown.js.map
index dacc764c41fba60b4a0674a5a2e17012cd821f8f..8fa0c127956564f059fc7082aa9deb53f04d5b6b 100644
GIT binary patch
delta 612
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delta 248
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diff --git a/dist/showdown.min.js b/dist/showdown.min.js
index 30c19ef0cce3b481fe5e732b344cf1a3d04e5a51..4a79107500d1747a7e34ea6691743f53d48286f1 100644
GIT binary patch
delta 247
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delta 41
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diff --git a/dist/showdown.min.js.map b/dist/showdown.min.js.map
index 2c7f5c4e50d13433ebcaf856bc35a1feb126bf5f..2a81f092f8392cbc485571955e219a1d4c2c7dad 100644
GIT binary patch
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diff --git a/src/options.js b/src/options.js
index 6e075a1..f2c4fa6 100644
--- a/src/options.js
+++ b/src/options.js
@@ -90,6 +90,11 @@ function getDefaultOpts(simple) {
       defaultValue: false,
       description: 'Parses simple line breaks as <br> (GFM Style)',
       type: 'boolean'
+    },
+    requireSpaceBeforeHeadingText: {
+      defaultValue: false,
+      description: 'Makes adding a space between `#` and the header text mandatory (GFM Style)',
+      type: 'boolean'
     }
   };
   if (simple === false) {
diff --git a/src/showdown.js b/src/showdown.js
index ed64ee8..46724c1 100644
--- a/src/showdown.js
+++ b/src/showdown.js
@@ -20,7 +20,8 @@ var showdown = {},
         ghCodeBlocks:                         true,
         tasklists:                            true,
         disableForced4SpacesIndentedSublists: true,
-        simpleLineBreaks:                     true
+        simpleLineBreaks:                     true,
+        requireSpaceBeforeHeadingText:        true
       },
       vanilla: getDefaultOpts(true)
     };
diff --git a/src/subParsers/headers.js b/src/subParsers/headers.js
index 5a79493..a6018f5 100644
--- a/src/subParsers/headers.js
+++ b/src/subParsers/headers.js
@@ -40,7 +40,9 @@ showdown.subParser('headers', function (text, options, globals) {
   //  ...
   //  ###### Header 6
   //
-  text = text.replace(/^(#{1,6})[ \t]*(.+?)[ \t]*#*\n+/gm, function (wholeMatch, m1, m2) {
+  var atxStyle = (options.requireSpaceBeforeHeadingText) ? /^(#{1,6})[ \t]+(.+?)[ \t]*#*\n+/gm : /^(#{1,6})[ \t]*(.+?)[ \t]*#*\n+/gm;
+
+  text = text.replace(atxStyle, function (wholeMatch, m1, m2) {
     var span = showdown.subParser('spanGamut')(m2, options, globals),
         hID = (options.noHeaderId) ? '' : ' id="' + headerId(m2) + '"',
         hLevel = headerLevelStart - 1 + m1.length,
diff --git a/test/features/requireSpaceBeforeHeadingText.html b/test/features/requireSpaceBeforeHeadingText.html
new file mode 100644
index 0000000..2610924
--- /dev/null
+++ b/test/features/requireSpaceBeforeHeadingText.html
@@ -0,0 +1,2 @@
+<h1 id="header">header</h1>
+<p>#header</p>
diff --git a/test/features/requireSpaceBeforeHeadingText.md b/test/features/requireSpaceBeforeHeadingText.md
new file mode 100644
index 0000000..c7eb76e
--- /dev/null
+++ b/test/features/requireSpaceBeforeHeadingText.md
@@ -0,0 +1,3 @@
+# header
+
+#header
diff --git a/test/node/testsuite.features.js b/test/node/testsuite.features.js
index c1a13d6..699a73c 100644
--- a/test/node/testsuite.features.js
+++ b/test/node/testsuite.features.js
@@ -39,6 +39,8 @@ describe('makeHtml() features testsuite', function () {
       converter = new showdown.Converter({simpleLineBreaks: true});
     } else if (testsuite[i].name === 'excludeTrailingPunctuationFromURLs-option') {
       converter = new showdown.Converter({simplifiedAutoLink: true, excludeTrailingPunctuationFromURLs: true});
+    } else if (testsuite[i].name === 'requireSpaceBeforeHeadingText') {
+      converter = new showdown.Converter({requireSpaceBeforeHeadingText: true});
     } else {
       converter = new showdown.Converter();
     }