1 files changed, 84 insertions, 0 deletions
diff --git a/tools/eslint/lib/rules/no-warning-comments.js b/tools/eslint/lib/rules/no-warning-comments.js
new file mode 100644
index 0000000000..58b6764ff1
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+++ b/tools/eslint/lib/rules/no-warning-comments.js
@@ -0,0 +1,84 @@
+/**
+ * @fileoverview Rule that warns about used warning comments
+ * @author Alexander Schmidt <https://github.com/lxanders>
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+module.exports = function (context) {
+
+    var configuration = context.options[0] || {},
+        warningTerms = configuration.terms || ["todo", "fixme", "xxx"],
+        location = configuration.location || "start",
+        warningRegExps;
+
+    /**
+     * Convert a warning term into a RegExp which will match a comment containing that whole word in the specified
+     * location ("start" or "anywhere"). If the term starts or ends with non word characters, then the match will not
+     * require word boundaries on that side.
+     *
+     * @param {String} term A term to convert to a RegExp
+     * @returns {RegExp} The term converted to a RegExp
+     */
+    function convertToRegExp(term) {
+        var escaped = term.replace(/[-\/\\$\^*+?.()|\[\]{}]/g, "\\$&"),
+            // If the term ends in a word character (a-z0-9_), ensure a word boundary at the end, so that substrings do
+            // not get falsely matched. eg "todo" in a string such as "mastodon".
+            // If the term ends in a non-word character, then \b won't match on the boundary to the next non-word
+            // character, which would likely be a space. For example `/\bFIX!\b/.test('FIX! blah') === false`.
+            // In these cases, use no bounding match. Same applies for the prefix, handled below.
+            suffix = /\w$/.test(term) ? "\\b" : "",
+            prefix;
+
+        if (location === "start") {
+            // When matching at the start, ignore leading whitespace, and there's no need to worry about word boundaries
+            prefix = "^\\s*";
+        } else if (/^\w/.test(term)) {
+            prefix = "\\b";
+        } else {
+            prefix = "";
+        }
+
+        return new RegExp(prefix + escaped + suffix, "i");
+    }
+
+    /**
+     * Checks the specified comment for matches of the configured warning terms and returns the matches.
+     * @param {String} comment The comment which is checked.
+     * @returns {Array} All matched warning terms for this comment.
+     */
+    function commentContainsWarningTerm(comment) {
+        var matches = [];
+
+        warningRegExps.forEach(function (regex, index) {
+            if (regex.test(comment)) {
+                matches.push(warningTerms[index]);
+            }
+        });
+
+        return matches;
+    }
+
+    /**
+     * Checks the specified node for matching warning comments and reports them.
+     * @param {ASTNode} node The AST node being checked.
+     * @returns {void} undefined.
+     */
+    function checkComment(node) {
+        var matches = commentContainsWarningTerm(node.value);
+
+        matches.forEach(function (matchedTerm) {
+            context.report(node, "Unexpected " + matchedTerm + " comment.");
+        });
+    }
+
+    warningRegExps = warningTerms.map(convertToRegExp);
+    return {
+        "BlockComment": checkComment,
+        "LineComment": checkComment
+    };
+};