runtime(syntax-tests): Retrofit input/c.c. with TEST_SETUP

Also:

- Include a syntax test for Markdown that takes advantage of
  a sourceable setup configuration.
- Update Filelist

closes: #14215

Signed-off-by: Aliaksei Budavei <0x000c70@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

3 files changed, 24 insertions, 0 deletions

diff --git a/runtime/syntax/testdir/input/c.c b/runtime/syntax/testdir/input/c.c
index c96fb33b4c..ede2cafb3d 100644
--- a/runtime/syntax/testdir/input/c.c
+++ b/runtime/syntax/testdir/input/c.c
@@ -1,4 +1,5 @@
 /* vi:set ts=8 sts=4 sw=4 noet:
+ * TEST_SETUP let g:c_comment_strings = 1
  *
  * VIM - Vi IMproved	by Bram Moolenaar
  *
diff --git a/runtime/syntax/testdir/input/markdown_conceal.markdown b/runtime/syntax/testdir/input/markdown_conceal.markdown
new file mode 100644
index 0000000000..8049d68a34
--- /dev/null
+++ b/runtime/syntax/testdir/input/markdown_conceal.markdown
@@ -0,0 +1,15 @@
+_Italic_, *Italic*.  __Bold__, **Bold**.  
+___Bold Italic___, ***Bold Italic***.  
+~~Strikethrough~~, S̶t̶r̶i̶k̶e̶t̶h̶r̶o̶u̶g̶h̶.
+
+~~~html
+<p>
+<del>Strikethrough</del>, <s>Strikethrough</s>.<br />
+~~~
+
+```html
+<strong><em>Bold Italic</em></strong>.
+<strong><em>Bold Italic</em></strong>.<br />
+<strong>Bold</strong>, <strong>Bold</strong>.
+<em>Italic</em>, <em>Italic</em>.
+```
diff --git a/runtime/syntax/testdir/input/setup/markdown_conceal.vim b/runtime/syntax/testdir/input/setup/markdown_conceal.vim
new file mode 100644
index 0000000000..a1585b18bb
--- /dev/null
+++ b/runtime/syntax/testdir/input/setup/markdown_conceal.vim
@@ -0,0 +1,8 @@
+if has('conceal')
+	let g:markdown_syntax_conceal = 1
+	setlocal conceallevel=3 concealcursor=n
+endif
+
+let g:markdown_fenced_languages = ['html']
+highlight link markdownBold Todo
+highlight link htmlBold Todo