add more flexibility to hyphen separated check; explicit em-dash check

rules/list-item.js

@@ -102,12 +102,19 @@ function validateList(list, file) {
 			continue;
 		}
 
-		const [link, ...description] = paragraph.children;
-
-		if (link.type === 'text') {
+		if (paragraph.children[0].type === 'text') {
 			continue;
 		}
 
+		let [link, ...description] = paragraph.children;
+
+		// Might have children like: '{image} {text} {link} { - description}'
+		// Keep discarding prefix elements until we find something link-like.
+		while (link.type !== 'linkReference' && link.type !== 'link' && description.length > 1) {
+			link = description[0];
+			description = description.slice(1);
+		}
+
 		if (!validateListItemLink(link, file)) {
 			continue;
 		}
@@ -117,6 +124,13 @@ function validateList(list, file) {
 }
 
 function validateListItemLink(link, file) {
+	// NB. We need remark-lint-no-undefined-references separately
+	// to catch if this is a valid reference. Here we only care that it exists.
+	if (link.type === 'linkReference') {
+		// TODO: need to test link children against listItemLinkNodeAllowList?
+		return true;
+	}
+
 	if (link.type !== 'link') {
 		file.message('Invalid list item link', link);
 		return false;
@@ -168,11 +182,18 @@ function validateListItemDescription(description, file) {
 			return false;
 		}
 
-		if (/^\s*—/.test(prefixText)) {
-			file.message('List item link and description separated by invalid en-dash', prefix);
+		// Some editors auto-correct ' - ' to – (en-dash). Also avoid — (em-dash).
+		if (/^\s*[/\u{02013}\u{02014}]/u.test(prefixText)) {
+			file.message('List item link and description separated by invalid en-dash or em-dash', prefix);
 			return false;
 		}
 
+		// Might have image and link on left side before description.
+		// Assume a hyphen with spaces in the description is good enough.
+		if (/ - [A-Z]/.test(descriptionText)) {
+			return true;
+		}
+
 		file.message('List item link and description must be separated with a dash', prefix);
 		return false;
 	}

test/fixtures/list-item/0.md

@@ -25,6 +25,8 @@ All list-items in this document should be linted as **valid**.
   - [foo](https://foo.com) - Valid sub-item.
     - [foo](https://foo.com) - Valid sub-sub-item!!!!!
 - [foo](https://foo.com) - GitHub's descriptions can also be valid.	
+- [foo-bar](https://foo-bar.com) - Valid description.
+- 👍 [foo](https://foo-bar.com) - Valid description.
 
 ## Tutorials
 
@@ -133,9 +135,16 @@ These sub-lists use mixed indentation (spaces and tabs).
 
 - [why-is-node-running](https://github.com/mafintosh/why-is-node-running) - Node.js is running but you don't know why?
 
-<!--
-TODO: these list-items should possibly lint as valid, but they currently don't.
 
-- ![v3](img/vapor-3.png) [API Error Middleware](https://github.com/skelpo/APIErrorMiddleware) – Vapor middleware for converting thrown errors to JSON responses.
-- ![v2](img/vapor-2.png) ![v3](img/vapor-3.png) [Bugsnag](https://github.com/nodes-vapor/bugsnag) – Report errors with Bugsnag.
+- [gtkada] - Ada graphical toolkit based on Gtk3 components (issue #161 link reference below but checked by `remark-lint-no-undefined-references` not `rules/list-item.js`).
+- [foo](https://foo.com) ![stars](https://img.shields.io/github/stars/foo/foo.svg) - Valid description.
+- ![v3](img/vapor-3.png) [API Error Middleware](https://github.com/skelpo/APIErrorMiddleware) - Vapor middleware for converting thrown errors to JSON responses.
+- ![v2](img/vapor-2.png) ![v3](img/vapor-3.png) [Bugsnag](https://github.com/nodes-vapor/bugsnag) - Report errors with Bugsnag.
+- [ArcGIS location services - Postman Workspace](https://www.postman.com/arcgis-developer/workspace/arcgis-location-services) - Official Postman collections to work with the Geocoding & Search API, Routing & Directions API, Demographics & GeoEnrichment API, Data hosting and more (issue #146).
+- [rmw](https://github.com/ros2/rmw/tree/master/rmw) - Contains the ROS middleware API ![rmw](https://img.shields.io/github/stars/ros2/rmw.svg) (issue #49).
+<!-- TODO 
+- [__Compiling machine learning programs via high-level tracing__. Roy Frostig, Matthew James Johnson, Chris Leary. _MLSys 2018_.](https://mlsys.org/Conferences/doc/2018/146.pdf) - This white paper describes an early version of JAX, detailing how computation is traced and compiled (issue #136)
 -->
+
+[gtkada]: https://github.com/AdaCore/gtkada
+

test/fixtures/list-item/1.md

@@ -70,3 +70,4 @@ Test description's ending punctuation.
 
 - [foo](https://foo.com) - Quote-inducing double punctuation “end…”??!
 - [foo](https://foo.com) - Quote-inducing double punctuation “end?…...”…...?
+- [gtkada] - reference link with no reference

test/rules/snapshots/list-item.js.md

@@ -46,7 +46,7 @@ Generated by [AVA](https://avajs.dev).
       },
       {
         line: 13,
-        message: 'List item link and description separated by invalid en-dash',
+        message: 'List item link and description separated by invalid en-dash or em-dash',
         ruleId: 'awesome-list-item',
       },
       {