updated to WCAG guidelines 1 -- 3; added a rule for checkpoint 3.5

3 files changed, 38 insertions, 57 deletions

diff --git a/guidelines/WCAG-1.0/guideline-1.js b/guidelines/WCAG-1.0/guideline-1.js
index 61e1384..ebbd823 100644
--- a/guidelines/WCAG-1.0/guideline-1.js
+++ b/guidelines/WCAG-1.0/guideline-1.js
@@ -3,7 +3,7 @@
  */
 
 exports.name        = "Equivalent Alternatives";
-exports.description = "";
+exports.description = "Web Accessibility Guideline: Provide equivalent alternatives to auditory and visual content";
 
 exports.rule        = function(report) {
 
@@ -11,21 +11,21 @@ exports.rule        = function(report) {
   /* Checkpoint 1.1 [Priority 1] **********************************************/
 
   var hasAlt = function(ix) {
-    // TODO: strip space from the alt attribute to prevent ' ' from passing
-    // the test
-    if(_.isEmpty($(this).attr('alt')) && _.isEmpty($(this).attr('longdesc'))) {
+    var alt = $.trim($(this).attr('alt'));
+    var longdesc = $.trim($(this).attr('longdesc'));
+    if(_.isEmpty(alt) && _.isEmpty(longdesc)) {
       report.error('No alt/longdesc specified', this);
     }
   };
 
   var hasText = function(ix) {
-    // TODO: strip space from the text to prevent ' ' from passing the test
-    if(_.isEmpty($(this).text())) {
+    if(_.isEmpty($.trim($(this).text()))) {
       report.error('No text node', this);
     }
   };
 
   // images with semantic meaning should have an alt attribute.
+  // TODO add a heuristic for detecting large images
   $5('a').find('img')
     .add($5('dl').find('img'))
     .add($5('dd').find('img'))
@@ -40,8 +40,6 @@ exports.rule        = function(report) {
   // All `object` tags must have a text node
   $5('object').each(hasText).each(hasAlt);
 
-  // TODO: what's the best way to classify content that's `complex`?
-
   // All `area` elements of an image map should have alt attributes. It's also a
   // bit overzealous, as it looks at all maps, not just maps that are referenced
   // from images.
@@ -62,23 +60,12 @@ exports.rule        = function(report) {
   // everything that the server does.  It's more of a sanity check, that this
   // has been thought of.
   $5('img').filter('[ismap]').each(function(ix) {
-    if(_.isEmpty($(this).attr('usemap'))) {
+    if(_.isEmpty($.trim($(this).attr('usemap')))) {
       report.error('No usemap attribute to supplement a use of ismap', this);
     }
   });
 
 
-  /* Checkpoint 1.3 [Priority 1] **********************************************/
-
-  // TODO: Not really sure if this is something that we can check; the guideline
-  // seems to be more of a subjective check.
-
-
-  /* Checkpoint 1.4 [Priority 1] **********************************************/
-
-  // TODO: Again, not sure if this is something we can check here.
-
-
   /* Checkpoint 1.5 [Priority 3] **********************************************/
 
   // Make sure that every link in an image map has a corresponding text link
diff --git a/guidelines/WCAG-1.0/guideline-2.js b/guidelines/WCAG-1.0/guideline-2.js
index 7dcf28d..206dd3e 100644
--- a/guidelines/WCAG-1.0/guideline-2.js
+++ b/guidelines/WCAG-1.0/guideline-2.js
@@ -1,13 +1,7 @@
-exports.name        = "colorDifference";
-exports.description = "Elements should provide sufficient color difference";
+exports.name        = "Color Difference";
+exports.description = "Web Accessibility Guideline: Don't rely on color alone";
 exports.rule        = function(report) {
 
-  /* Checkpoint 2.1 ***********************************************************/
-
-  // TODO: not sure about the best way to test that information isn't hidden
-  // when colors go away.
-
-
   /* Checkpoint 2.2 ***********************************************************/
 
   var fc = fiveui.color;
@@ -30,7 +24,6 @@ exports.rule        = function(report) {
       return $this.children().length == 0 && $.trim($this.text()).length > 0;
     })
     .each(function (i) {
-      // TODO take into account fg alpha values
       var fg = fc.colorToRGB($(this).css('color'));
       var bg = fc.findBGColor($(this));
       if (fg && bg) {
diff --git a/guidelines/WCAG-1.0/guideline-3.js b/guidelines/WCAG-1.0/guideline-3.js
index 1be4354..0f6055b 100644
--- a/guidelines/WCAG-1.0/guideline-3.js
+++ b/guidelines/WCAG-1.0/guideline-3.js
@@ -1,20 +1,11 @@
 
-exports.name        = 'W3C Guideline 3';
-exports.description = '';
+exports.name        = 'Proper Markup and Stylesheets';
+exports.description = 'Web Accessibility Guideline: Use markup and style sheets and do so properly';
 exports.rule        = function(report) {
 
-  /* Checkpoint 3.1 [Priority 2] **********************************************/
-
-  // TODO: this seems pretty subjective, as you have to be able to understand
-  // the intent of the content.  The math example is tough, as you'd have to be
-  // able to pick out a situation where text wasn't marked up, but was also
-  // mathematical notation.
-
-
   /* Checkpoint 3.2 [Priority 2] **********************************************/
 
   // require that the document contains a dtd.
-  // TODO: how should we apply this check to iframes and such?
   if(!document.doctype) {
     report.error('No doctype given for the document', null);
   }
@@ -36,22 +27,36 @@ exports.rule        = function(report) {
     report.error('Use css instead of the font attribute for formatting', this);
   });
 
-  // TODO: there are other cases to handle here, not sure about the best path
-  // forward.
-
-
-  /* Checkpoint 3.4 [Priority 2] **********************************************/
-
-  // TODO: not sure what the best way to select everything that's not
-  // automatically positioned.  Additionally, many fancy user interfaces will
-  // use pixels when positioning content, which isn't necessarily wrong.
-
 
   /* Checkpoint 3.5 [Priority 2] **********************************************/
 
-  // TODO: what's the best way to select siblings that match a given pattern in
-  // jquery?  Essentially, we just want to match situations where h1 is followed
-  // by something that's both a header, and not h2 (for example).
+  // header transitions which are not allowed
+  var avoids = [ ["H1", "H3"]
+               , ["H1", "H4"]
+               , ["H1", "H5"]
+               , ["H2", "H4"]
+               , ["H2", "H5"]
+               , ["H3", "H5"] ];
+
+  // return true if the value `p` is in `avoids`. underscore's
+  // _.contains doesn't work here because it compares array references
+  var badPair = function (p) {
+    return _.find(avoids, function (s) {
+      return s[0] == p[0] && s[1] == p[1];
+    });
+  };
+
+  // examine the sequence of headings in each <div> for
+  // proper order
+  $('div').each(function (i, elt) {
+    var hs = $(elt).find(':header');
+    var ts = $(hs).map(function () { return this.tagName; });
+    for (var j=0; j < hs.length-1; j++) {
+      if (badPair([ts[j], ts[j+1]])) {
+        report.error('Invalid use of headers ' + ts[j] + ' -> ' + ts[j+1], hs[j+1]);
+      }
+    }
+  });
 
 
   /* Checkpoint 3.6 [Priority 2] **********************************************/
@@ -59,8 +64,4 @@ exports.rule        = function(report) {
 
   /* Checkpoint 3.7 [Priority 2] **********************************************/
 
-  // TODO: is there any way that we can detect quotations that aren't inside of
-  // a blockquote region?
-
-
 };