Merge pull request #187 from jyasskin/reject-empty-filters

Block an empty list of filters.
WebBluetoothCG · Nov 9, 2015 · b62a8e5 · b62a8e5
2 parents e8dba07 + 3722594
commit b62a8e5
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Showing 2 changed files with 41 additions and 7 deletions.
diff --git a/index.bs b/index.bs
@@ -720,22 +720,38 @@ spec: html
         </td>
         <td>D3, D5</td>
       </tr>
+    </table>
+  </div>
+
+  <div class="example" id="example-disallowed-filters">
+    <p>
+      Filters that either accept or reject all possible devices cause {{TypeError}}s.
+    </p>
+
+    <table>
+      <tr><th><var>filters</var></th><th>Notes</th></tr>
+      <tr>
+        <td>
+          <pre highlight="js">
+            []
+          </pre>
+        </td>
+        <td>An empty list of filters doesn't accept any devices.</td>
+      </tr>
       <tr>
         <td>
           <pre highlight="js">
             [{}]
           </pre>
         </td>
-        <td><i>TypeError</i></td>
-        <td>A filter must restrict the devices in some way.</td>
+        <td>An empty filter accepts all devices, and so isn't allowed either.</td>
       </tr>
       <tr>
         <td>
           <pre highlight="js">
             [{namePrefix: ""}]
           </pre>
         </td>
-        <td><i>TypeError</i></td>
         <td>`namePrefix`, if present, must be non-empty to filter devices.</td>
       </tr>
     </table>
@@ -797,6 +813,11 @@ spec: html
       In order to convert the arguments from service names and aliases to just <a>UUID</a>s,
       do the following substeps:
       <ol>
+        <li>
+          If <code><var>options</var>.filters.length === 0</code>,
+          <a>reject</a> <var>promise</var> with a {{TypeError}}
+          and abort these steps.
+        </li>
         <li>
           Let <var>uuidFilters</var> be a new {{Array}} and
           <var>requiredServiceUUIDs</var> be a new {{Set}}.

diff --git a/index.html b/index.html
@@ -1072,7 +1072,7 @@
   <div class="head">
    <div data-fill-with="logo"></div>
    <h1 class="p-name no-ref" id="title">Web Bluetooth</h1>
-   <h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Draft Community Group Report, <time class="dt-updated" datetime="2015-10-30">30 October 2015</time></span></h2>
+   <h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Draft Community Group Report, <time class="dt-updated" datetime="2015-11-09">9 November 2015</time></span></h2>
    <div data-fill-with="spec-metadata">
     <dl>
      <dt>This version:
@@ -1610,15 +1610,27 @@ <h2 class="heading settled" data-level="3" id="device-discovery"><span class="se
   <span class="nx">namePrefix</span><span class="o">:</span> <span class="s2">"Device"</span><span class="p">},</span>
  <span class="p">{</span><span class="nx">name</span><span class="o">:</span> <span class="s2">"Unique Name"</span><span class="p">}]</span></pre>
         <td>D3, D5
+     </table>
+    </div>
+    <div class="example" id="example-disallowed-filters">
+     <a class="self-link" href="#example-disallowed-filters"></a> 
+     <p> Filters that either accept or reject all possible devices cause <code class="idl"><a data-link-type="idl" href="http://ecma-international.org/ecma-262/6.0/#sec-native-error-types-used-in-this-standard-typeerror">TypeError</a></code>s. </p>
+     <table>
+      <tbody>
+       <tr>
+        <th><var>filters</var>
+        <th>Notes
+       <tr>
+        <td>
+<pre class="highlight"><span class="p">[]</span></pre>
+        <td>An empty list of filters doesn’t accept any devices.
        <tr>
         <td>
 <pre class="highlight"><span class="p">[{}]</span></pre>
-        <td><i>TypeError</i>
-        <td>A filter must restrict the devices in some way.
+        <td>An empty filter accepts all devices, and so isn’t allowed either.
        <tr>
         <td>
 <pre class="highlight"><span class="p">[{</span><span class="nx">namePrefix</span><span class="o">:</span> <span class="s2">""</span><span class="p">}]</span></pre>
-        <td><i>TypeError</i>
         <td><code>namePrefix</code>, if present, must be non-empty to filter devices.
      </table>
     </div>
@@ -1655,6 +1667,7 @@ <h2 class="heading settled" data-level="3" id="device-discovery"><span class="se
        In order to convert the arguments from service names and aliases to just <a data-link-type="dfn" href="#uuid">UUID</a>s,
       do the following substeps: 
       <ol>
+       <li> If <code><var>options</var>.filters.length === 0</code>, <a data-link-type="dfn" href="https://www.w3.org/2001/tag/doc/promises-guide#reject-promise">reject</a> <var>promise</var> with a <code class="idl"><a data-link-type="idl" href="http://ecma-international.org/ecma-262/6.0/#sec-native-error-types-used-in-this-standard-typeerror">TypeError</a></code> and abort these steps. 
        <li> Let <var>uuidFilters</var> be a new <code class="idl"><a data-link-type="idl" href="http://ecma-international.org/ecma-262/6.0/#sec-array-objects">Array</a></code> and <var>requiredServiceUUIDs</var> be a new <code class="idl"><a data-link-type="idl" href="http://ecma-international.org/ecma-262/6.0/#sec-set-objects">Set</a></code>. 
        <li>
          For each <var>filter</var> in <code><var>options</var>.filters</code>,