Update MD039/no-space-in-links to handle RegExp match failure (fixes #262).

lib/md039.js

@@ -28,22 +28,28 @@ module.exports = {
           const right = linkText.trimRight().length !== linkText.length;
           if (left || right) {
             const line = params.lines[lineNumber - 1];
+            let range = null;
+            let fixInfo = null;
             const match = line.slice(lineIndex).match(spaceInLinkRe);
-            const column = match.index + lineIndex + 1;
+            if (match) {
-            const length = match[0].length;
+              const column = match.index + lineIndex + 1;
-            lineIndex = column + length - 1;
+              const length = match[0].length;
+              range = [ column, length ];
+              fixInfo = {
+                "editColumn": column + 1,
+                "deleteCount": length - 2,
+                "insertText": linkText.trim()
+              };
+              lineIndex = column + length - 1;
+            }
             addErrorContext(
               onError,
               lineNumber,
               `[${linkText}]`,
               left,
               right,
-              [ column, length ],
+              range,
-              {
+              fixInfo
-                "editColumn": column + 1,
-                "deleteCount": length - 2,
-                "insertText": linkText.trim()
-              }
             );
           }
         } else if ((type === "softbreak") || (type === "hardbreak")) {

test/spaces_inside_link_text.md

@@ -45,3 +45,8 @@ function MoreCodeButNotCode(input) {
 [Links](ending)  
 [with](spaces)  
 [error ]({MD039})
+
+Wrapped [ link with leading space
+  ](https://example.com) {MD039}
+
+Non-wrapped [ link with leading space](https://example.com) {MD039}