Add link, images (resource)

This is still some messy code that needs cleaning up, but it adds support for
links and images, of the resource kind (`[a](b)`).
References (`[a][b]`) are parsed and will soon be supported, but need matching.

*   Fix bug to pad percent-encoded bytes when normalizing urls
*   Fix bug with escapes counting as balancing in destination
*   Add `space_or_tab_one_line_ending`, to parse whitespace including up to
    one line ending (but not a blank line)
*   Add `ParserState` to share codes, definitions, etc

1 files changed, 229 insertions, 0 deletions

diff --git a/tests/image.rs b/tests/image.rs
new file mode 100644
index 0000000..a54c8d2
--- /dev/null
+++ b/tests/image.rs
@@ -0,0 +1,229 @@
+extern crate micromark;
+use micromark::micromark;
+
+#[test]
+fn image() {
+    assert_eq!(
+        micromark("[link](/uri \"title\")"),
+        "<p><a href=\"/uri\" title=\"title\">link</a></p>",
+        "should support links"
+    );
+    assert_eq!(
+        micromark("![foo](/url \"title\")"),
+        "<p><img src=\"/url\" alt=\"foo\" title=\"title\" /></p>",
+        "should support image w/ resource"
+    );
+
+    // To do: attention.
+    // assert_eq!(
+    //     micromark("[foo *bar*]: train.jpg \"train & tracks\"\n\n![foo *bar*]"),
+    //     "<p><img src=\"train.jpg\" alt=\"foo bar\" title=\"train &amp; tracks\" /></p>",
+    //     "should support image as shortcut reference"
+    // );
+
+    // To do: tags in images.
+    // assert_eq!(
+    //     micromark("![foo ![bar](/url)](/url2)"),
+    //     "<p><img src=\"/url2\" alt=\"foo bar\" /></p>",
+    //     "should “support” images in images"
+    // );
+
+    // To do: tags in images.
+    // assert_eq!(
+    //     micromark("![foo [bar](/url)](/url2)"),
+    //     "<p><img src=\"/url2\" alt=\"foo bar\" /></p>",
+    //     "should “support” links in images"
+    // );
+
+    // To do: tags in images.
+    // assert_eq!(
+    //     micromark("[foo *bar*]: train.jpg \"train & tracks\"\n\n![foo *bar*][]"),
+    //     "<p><img src=\"train.jpg\" alt=\"foo bar\" title=\"train &amp; tracks\" /></p>",
+    //     "should support “content” in images"
+    // );
+
+    // To do: tags in images, attention, references.
+    // assert_eq!(
+    //     micromark("[FOOBAR]: train.jpg \"train & tracks\"\n\n![foo *bar*][foobar]"),
+    //     "<p><img src=\"train.jpg\" alt=\"foo bar\" title=\"train &amp; tracks\" /></p>",
+    //     "should support “content” in images"
+    // );
+
+    assert_eq!(
+        micromark("![foo](train.jpg)"),
+        "<p><img src=\"train.jpg\" alt=\"foo\" /></p>",
+        "should support images w/o title"
+    );
+
+    assert_eq!(
+        micromark("My ![foo bar](/path/to/train.jpg  \"title\"   )"),
+        "<p>My <img src=\"/path/to/train.jpg\" alt=\"foo bar\" title=\"title\" /></p>",
+        "should support images w/ lots of whitespace"
+    );
+
+    assert_eq!(
+        micromark("![foo](<url>)"),
+        "<p><img src=\"url\" alt=\"foo\" /></p>",
+        "should support images w/ enclosed destinations"
+    );
+
+    assert_eq!(
+        micromark("![](/url)"),
+        "<p><img src=\"/url\" alt=\"\" /></p>",
+        "should support images w/ empty labels"
+    );
+
+    // To do: references.
+    // assert_eq!(
+    //     micromark("[bar]: /url\n\n![foo][bar]"),
+    //     "<p><img src=\"/url\" alt=\"foo\" /></p>",
+    //     "should support full references (1)"
+    // );
+
+    // To do: references.
+    // assert_eq!(
+    //     micromark("[BAR]: /url\n\n![foo][bar]"),
+    //     "<p><img src=\"/url\" alt=\"foo\" /></p>",
+    //     "should support full references (2)"
+    // );
+
+    // To do: references.
+    // assert_eq!(
+    //     micromark("[foo]: /url \"title\"\n\n![foo][]"),
+    //     "<p><img src=\"/url\" alt=\"foo\" title=\"title\" /></p>",
+    //     "should support collapsed references (1)"
+    // );
+
+    // To do: references, attention, tags in images.
+    // assert_eq!(
+    //     micromark("[*foo* bar]: /url \"title\"\n\n![*foo* bar][]"),
+    //     "<p><img src=\"/url\" alt=\"foo bar\" title=\"title\" /></p>",
+    //     "should support collapsed references (2)"
+    // );
+
+    // To do: references.
+    // assert_eq!(
+    //     micromark("[foo]: /url \"title\"\n\n![Foo][]"),
+    //     "<p><img src=\"/url\" alt=\"Foo\" title=\"title\" /></p>",
+    //     "should support case-insensitive labels"
+    // );
+
+    // To do: references.
+    // assert_eq!(
+    //     micromark("[foo]: /url \"title\"\n\n![foo] \n[]"),
+    //     "<p><img src=\"/url\" alt=\"foo\" title=\"title\" />\n[]</p>",
+    //     "should not support whitespace between sets of brackets"
+    // );
+
+    // To do: references.
+    // assert_eq!(
+    //     micromark("[foo]: /url \"title\"\n\n![foo]"),
+    //     "<p><img src=\"/url\" alt=\"foo\" title=\"title\" /></p>",
+    //     "should support shortcut references (1)"
+    // );
+
+    // To do: references, tags in images, attention.
+    // assert_eq!(
+    //     micromark("[*foo* bar]: /url \"title\"\n\n![*foo* bar]"),
+    //     "<p><img src=\"/url\" alt=\"foo bar\" title=\"title\" /></p>",
+    //     "should support shortcut references (2)"
+    // );
+
+    assert_eq!(
+        micromark("[[foo]]: /url \"title\"\n\n![[foo]]"),
+        "<p>[[foo]]: /url &quot;title&quot;</p>\n<p>![[foo]]</p>",
+        "should not support link labels w/ unescaped brackets"
+    );
+
+    // To do: references.
+    // assert_eq!(
+    //     micromark("[foo]: /url \"title\"\n\n![Foo]"),
+    //     "<p><img src=\"/url\" alt=\"Foo\" title=\"title\" /></p>",
+    //     "should support case-insensitive label matching"
+    // );
+
+    // To do: references.
+    // assert_eq!(
+    //     micromark("[foo]: /url \"title\"\n\n!\\[foo]"),
+    //     "<p>![foo]</p>",
+    //     "should “support” an escaped bracket instead of an image"
+    // );
+
+    // To do: references.
+    // assert_eq!(
+    //     micromark("[foo]: /url \"title\"\n\n\\![foo]"),
+    //     "<p>!<a href=\"/url\" title=\"title\">foo</a></p>",
+    //     "should support an escaped bang instead of an image, but still have a link"
+    // );
+
+    // Extra
+    assert_eq!(
+        micromark("![foo]()"),
+        "<p><img src=\"\" alt=\"foo\" /></p>",
+        "should support images w/o destination"
+    );
+
+    assert_eq!(
+        micromark("![foo](<>)"),
+        "<p><img src=\"\" alt=\"foo\" /></p>",
+        "should support images w/ explicit empty destination"
+    );
+
+    assert_eq!(
+        micromark("![](example.png)"),
+        "<p><img src=\"example.png\" alt=\"\" /></p>",
+        "should support images w/o alt"
+    );
+
+    assert_eq!(
+        micromark("![alpha](bravo.png \"\")"),
+        "<p><img src=\"bravo.png\" alt=\"alpha\" /></p>",
+        "should support images w/ empty title (1)"
+    );
+
+    assert_eq!(
+        micromark("![alpha](bravo.png '')"),
+        "<p><img src=\"bravo.png\" alt=\"alpha\" /></p>",
+        "should support images w/ empty title (2)"
+    );
+
+    assert_eq!(
+        micromark("![alpha](bravo.png ())"),
+        "<p><img src=\"bravo.png\" alt=\"alpha\" /></p>",
+        "should support images w/ empty title (3)"
+    );
+
+    assert_eq!(
+    micromark("![&amp;&copy;&](example.com/&amp;&copy;& \"&amp;&copy;&\")"),
+    "<p><img src=\"example.com/&amp;%C2%A9&amp;\" alt=\"&amp;©&amp;\" title=\"&amp;©&amp;\" /></p>",
+    "should support character references in images"
+  );
+
+    // Extra
+    // See: <https://github.com/commonmark/commonmark.js/issues/192>
+    assert_eq!(
+        micromark("![](<> \"\")"),
+        "<p><img src=\"\" alt=\"\" /></p>",
+        "should ignore an empty title"
+    );
+
+    // To do: extensions
+    // assert_eq!(
+    //   micromark("![x]()", {extensions: [{disable: {null: ["labelStartImage"]}}]}),
+    //   "<p>!<a href=\"\">x</a></p>",
+    //   "should support turning off label start (image)"
+    // );
+
+    assert_eq!(
+        micromark("![](javascript:alert(1))"),
+        "<p><img src=\"\" alt=\"\" /></p>",
+        "should ignore non-http protocols by default"
+    );
+
+    // To do: extensions
+    // assert_eq!(
+    //   micromark("![](javascript:alert(1))", {allowDangerousProtocol: true}),
+    //   "<p><img src=\"javascript:alert(1)\" alt=\"\" /></p>",
+    //   "should allow non-http protocols w/ `allowDangerousProtocol`"
+    // );
+}