Merge pull request #422 from hypothesis/extract-app-function

Extract app() into separate function

src/annotator/config/index.js

@@ -12,9 +12,9 @@ var docs = 'https://h.readthedocs.io/en/latest/embedding.html';
  */
 function configFrom(window_) {
   var config = {
-    app: window_.
-      document.querySelector('link[type="application/annotator+html"]').href,
+    app: settings.app(window_.document),
   };
+
   var chromeExt = 'chrome-extension://';
   var mozExt = 'moz-extension://';
   var edgeExt = 'ms-browser-extension://';

src/annotator/config/settings.js

 'use strict';
 
+/**
+ * Return the href URL of the first annotator link in the given document.
+ *
+ * Return the value of the href attribute of the first
+ * `<link type="application/annotator+html">` element in the given document.
+ *
+ * This URL is used as the src of the sidebar's iframe.
+ *
+ * @param {Document} - The document to search.
+ * @return {string} - The URL to use for the sidebar's iframe.
+ *
+ * @throws {Error} - If there's no annotator link or the first annotator has
+ *   no href.
+ *
+ */
+function app(document_) {
+  var link = document_.querySelector('link[type="application/annotator+html"]');
+
+  if (!link) {
+    throw new Error('No application/annotator+html link in the document');
+  }
+
+  if (!link.href) {
+    throw new Error('application/annotator+html link has no href');
+  }
+
+  return link.href;
+}
+
 /**
  * Return the `#annotations:*` ID from the given URL's fragment.
  *
@@ -42,6 +71,7 @@ function query(url) {
 }
 
 module.exports = {
+  app: app,
   annotations: annotations,
   query: query,
 };

src/annotator/config/test/index-test.js

 'use strict';
 
 var proxyquire = require('proxyquire');
+var util = require('../../../shared/test/util');
 
 var fakeSharedSettings = {};
 var fakeSettings = {};
 
-var configFrom = proxyquire('../index', {
+var configFrom = proxyquire('../index', util.noCallThru({
   './settings': fakeSettings,
   '../../shared/settings': fakeSharedSettings,
-});
+}));
 var sandbox = sinon.sandbox.create();
 
-function fakeWindow(someHref) {
-  var href = someHref || 'LINK_HREF';
-
+function fakeWindow() {
   return {
-    document: {
-      querySelector: sinon.stub().returns({href: href}),
-    },
+    document: 'THE_DOCUMENT',
     location: {href: 'LOCATION_HREF'},
   };
 }
@@ -32,6 +29,7 @@ describe('annotator.config', function() {
   });
 
   beforeEach('reset fakeSettings', function() {
+    fakeSettings.app = sinon.stub().returns('IFRAME_URL');
     fakeSettings.annotations = sinon.stub();
     fakeSettings.query = sinon.stub();
   });
@@ -40,31 +38,31 @@ describe('annotator.config', function() {
     sandbox.restore();
   });
 
-  context("when there's an application/annotator+html <link>", function() {
-    var link;
+  it('gets the config.app setting', function() {
+    var window_ = fakeWindow();
 
-    beforeEach('add an application/annotator+html <link>', function() {
-      link = document.createElement('link');
-      link.type = 'application/annotator+html';
-      link.href = 'http://example.com/link';
-      document.head.appendChild(link);
-    });
+    configFrom(window_);
 
-    afterEach('tidy up the link', function() {
-      document.head.removeChild(link);
+    assert.calledOnce(fakeSettings.app);
+    assert.calledWith(fakeSettings.app, window_.document);
   });
 
+  context("when there's an application/annotator+html <link>", function() {
     it("returns the <link>'s href as config.app", function() {
-      assert.equal(configFrom(window).app, link.href);
+      assert.equal(configFrom(fakeWindow()).app, 'IFRAME_URL');
     });
   });
 
   context("when there's no application/annotator+html <link>", function() {
-    it('throws a TypeError', function() {
-      var window_ = fakeWindow();
-      window_.document.querySelector.returns(null);
+    beforeEach('remove the application/annotator+html <link>', function() {
+      fakeSettings.app.throws(new Error("there's no link"));
+    });
 
-      assert.throws(function() { configFrom(window_); }, TypeError);
+    it('throws an error', function() {
+      assert.throws(
+        function() { configFrom(fakeWindow()); },
+        "there's no link"
+      );
     });
   });
 
@@ -231,46 +229,50 @@ describe('annotator.config', function() {
     });
 
     it('ignores the host page config on chrome', function() {
-      var window_ = fakeWindow('chrome-extension://abcdef');
-      var currConfig = configFrom(window_);
+      fakeSettings.app.returns('chrome-extension://abcdef');
 
-      assert.equal(currConfig.app, 'chrome-extension://abcdef');
-      assert.equal(currConfig.annotations, 'SOME_ANNOTATION_ID');
-      assert.isUndefined(currConfig.foo);
+      var config = configFrom(fakeWindow());
+
+      assert.equal(config.app, 'chrome-extension://abcdef');
+      assert.equal(config.annotations, 'SOME_ANNOTATION_ID');
+      assert.isUndefined(config.foo);
     });
 
     it('ignores the host page config on firefox', function() {
-      var window_ = fakeWindow('moz-extension://abcdef');
-      var currConfig = configFrom(window_);
+      fakeSettings.app.returns('moz-extension://abcdef');
+
+      var config = configFrom(fakeWindow());
 
-      assert.equal(currConfig.app, 'moz-extension://abcdef');
-      assert.equal(currConfig.annotations, 'SOME_ANNOTATION_ID');
-      assert.isUndefined(currConfig.foo);
+      assert.equal(config.app, 'moz-extension://abcdef');
+      assert.equal(config.annotations, 'SOME_ANNOTATION_ID');
+      assert.isUndefined(config.foo);
     });
 
     it('ignores the host page config on edge', function() {
-      var window_ = fakeWindow('ms-browser-extension://abcdef');
-      var currConfig = configFrom(window_);
+      fakeSettings.app.returns('ms-browser-extension://abcdef');
 
-      assert.equal(currConfig.app, 'ms-browser-extension://abcdef');
-      assert.equal(currConfig.annotations, 'SOME_ANNOTATION_ID');
-      assert.isUndefined(currConfig.foo);
+      var config = configFrom(fakeWindow());
+
+      assert.equal(config.app, 'ms-browser-extension://abcdef');
+      assert.equal(config.annotations, 'SOME_ANNOTATION_ID');
+      assert.isUndefined(config.foo);
     });
   });
 
   context('when the client is not injected by the browser extension', function() {
-    beforeEach(function() {
-      fakeSettings.annotations.returns('SOME_ANNOTATION_ID');
-      fakeSharedSettings.jsonConfigsFrom.returns({foo: 'bar'});
+    beforeEach('configure an embedded client', function() {
+      fakeSettings.app.returns('https://hypothes.is/app.html');
     });
 
     it('does not ignore the host page config', function() {
-      var window_ = fakeWindow('SOME_HREF');
-      var currConfig = configFrom(window_);
+      fakeSettings.annotations.returns('SOME_ANNOTATION_ID');
+      fakeSharedSettings.jsonConfigsFrom.returns({foo: 'bar'});
 
-      assert.equal(currConfig.app, 'SOME_HREF');
-      assert.equal(currConfig.annotations, 'SOME_ANNOTATION_ID');
-      assert.equal(currConfig.foo, 'bar');
+      var config = configFrom(fakeWindow());
+
+      assert.equal(config.app, 'https://hypothes.is/app.html');
+      assert.equal(config.annotations, 'SOME_ANNOTATION_ID');
+      assert.equal(config.foo, 'bar');
     });
   });
 });

src/annotator/config/test/settings-test.js

@@ -3,6 +3,81 @@
 var settings = require('../settings');
 
 describe('annotation.config.settings', function() {
+  describe('#app', function() {
+    function appendLinkToDocument(href) {
+      var link = document.createElement('link');
+      link.type = 'application/annotator+html';
+      if (href) {
+        link.href = href;
+      }
+      document.head.appendChild(link);
+      return link;
+    }
+
+    context("when there's an application/annotator+html link", function() {
+      var link;
+
+      beforeEach('add an application/annotator+html <link>', function() {
+        link = appendLinkToDocument('http://example.com/app.html');
+      });
+
+      afterEach('tidy up the link', function() {
+        document.head.removeChild(link);
+      });
+
+      it('returns the href from the link', function() {
+        assert.equal(settings.app(document), 'http://example.com/app.html');
+      });
+    });
+
+    context('when there are multiple annotator+html links', function() {
+      var link1;
+      var link2;
+
+      beforeEach('add two links to the document', function() {
+        link1 = appendLinkToDocument('http://example.com/app1');
+        link2 = appendLinkToDocument('http://example.com/app2');
+      });
+
+      afterEach('tidy up the links', function() {
+        document.head.removeChild(link1);
+        document.head.removeChild(link2);
+      });
+
+      it('returns the href from the first one', function() {
+        assert.equal(settings.app(document), 'http://example.com/app1');
+      });
+    });
+
+    context('when the annotator+html link has no href', function() {
+      var link;
+
+      beforeEach('add an application/annotator+html <link> with no href', function() {
+        link = appendLinkToDocument();
+      });
+
+      afterEach('tidy up the link', function() {
+        document.head.removeChild(link);
+      });
+
+      it('throws an error', function() {
+        assert.throws(
+          function() { settings.app(document); },
+          'application/annotator+html link has no href'
+        );
+      });
+    });
+
+    context("when there's no annotator+html link", function() {
+      it('throws an error', function() {
+        assert.throws(
+          function() { settings.app(document); },
+          'No application/annotator+html link in the document'
+        );
+      });
+    });
+  });
+
   describe('#annotations', function() {
     [
       {