Merge pull request #4075 from msrose/docs-search

Add filtering to documentation

docs/search.js

@@ -0,0 +1,58 @@
+(function() {
+  var functions = document.querySelectorAll('[data-name]');
+  var sections = document.querySelectorAll('.searchable_section');
+  var searchInput = document.getElementById('function_filter');
+
+  function strIn(a, b) {
+    a = a.toLowerCase();
+    b = b.toLowerCase();
+    return b.indexOf(a) >= 0;
+  }
+
+  function doesMatch(element) {
+    var name = element.getAttribute('data-name');
+    var aliases = element.getAttribute('data-aliases') || '';
+    return strIn(searchInput.value, name) || strIn(searchInput.value, aliases);
+  }
+
+  function filterElement(element) {
+    element.style.display = doesMatch(element) ? '' : 'none';
+  }
+
+  function filterToc() {
+    _.each(functions, filterElement);
+
+    var emptySearch = searchInput.value === '';
+
+    // Hide the titles of empty sections
+    _.each(sections, function(section) {
+      var sectionFunctions = section.querySelectorAll('[data-name]');
+      var showSection = emptySearch || _.some(sectionFunctions, doesMatch);
+      section.style.display = showSection ? '' : 'none';
+    });
+  }
+
+  function gotoFirst() {
+    var firstFunction = _.find(functions, doesMatch);
+    if(firstFunction) {
+      window.location.hash = firstFunction.lastChild.getAttribute('href');
+      searchInput.focus();
+    }
+  }
+
+  searchInput.addEventListener('input', filterToc, false);
+
+  // Press "Enter" to jump to the first matching function
+  searchInput.addEventListener('keypress', function(e) {
+    if (e.which === 13) {
+      gotoFirst();
+    }
+  });
+
+  // Press "/" to search
+  document.body.addEventListener('keyup', function(event) {
+    if (191 === event.which) {
+      searchInput.focus();
+    }
+  });
+}());