diff --git a/tests/lib/execute-scripts.js b/tests/lib/execute-scripts.js
index 2fdd39e..0d93e15 100644
--- a/tests/lib/execute-scripts.js
+++ b/tests/lib/execute-scripts.js
@@ -14,3 +14,16 @@ tape("test executeScripts method when the script tag is inside a container", fun
 
   t.end()
 })
+
+tape("test executeScripts method with just a script tag", function(t) {
+  document.body.className = ""
+
+  var script = document.createElement("script")
+  script.innerHTML = "document.body.className = 'executed correctly';"
+
+  t.equal(document.body.className, "", "script hasn't been executed yet")
+  executeScripts(script)
+  t.equal(document.body.className, "executed correctly", "script has been properly executed")
+
+  t.end()
+})
diff --git a/tests/lib/proto/attach-form.js b/tests/lib/proto/attach-form.js
index fbb243d..249afc8 100644
--- a/tests/lib/proto/attach-form.js
+++ b/tests/lib/proto/attach-form.js
@@ -98,3 +98,57 @@ tape("test options are not modified by attachForm", function(t) {
 
   t.end()
 })
+
+tape("test submit triggered by keyboard", function(t) {
+  var form = document.createElement("form")
+  var pjax = {
+    options: {},
+    loadUrl: function() {
+      t.equal(form.getAttribute(attr), "submit", "triggering a internal link actually submits the form")
+    }
+  }
+
+  t.plan(2)
+
+  attachForm.call(pjax, form)
+
+  form.action = window.location.protocol + "//" + window.location.host + "/internal"
+
+  trigger(form, "keyup", {keyCode: 14})
+  t.equal(form.getAttribute(attr), "", "keycode other than 13 doesn't trigger anything")
+
+  trigger(form, "keyup", {keyCode: 13})
+  // see loadUrl defined above
+
+  t.end()
+})
+
+tape("test form elements parsed correctly", function(t) {
+  t.plan(1)
+
+  var form = document.createElement("form")
+  var input = document.createElement("input")
+  input.name = "input"
+  input.value = "value"
+  form.appendChild(input)
+
+  var params = [{
+    name: "input",
+    value: "value"
+  }]
+  var pjax = {
+    options: {},
+    loadUrl: function(href, options) {
+      t.same(options.requestOptions.requestParams, params, "form elements parsed correctly")
+    }
+  }
+
+  attachForm.call(pjax, form)
+
+  form.action = window.location.protocol + "//" + window.location.host + "/internal"
+
+  trigger(form, "submit")
+  // see loadUrl defined above
+
+  t.end()
+})
diff --git a/tests/lib/proto/attach-link.js b/tests/lib/proto/attach-link.js
index 113ea83..fb88682 100644
--- a/tests/lib/proto/attach-link.js
+++ b/tests/lib/proto/attach-link.js
@@ -88,3 +88,56 @@ tape("test options are not modified by attachLink", function(t) {
 
   t.end()
 })
+
+tape("test link triggered by keyboard", function(t) {
+  var a = document.createElement("a")
+  var pjax = {
+    options: {},
+    loadUrl: function() {
+      t.equal(a.getAttribute(attr), "load", "triggering a internal link actually loads the page")
+    }
+  }
+
+  t.plan(3)
+
+  attachLink.call(pjax, a)
+
+  a.href = window.location.protocol + "//" + window.location.host + "/internal"
+
+  trigger(a, "keyup", {keyCode: 14})
+  t.equal(a.getAttribute(attr), "", "keycode other than 13 doesn't trigger anything")
+
+  trigger(a, "keyup", {keyCode: 13, metaKey: true})
+  t.equal(a.getAttribute(attr), "modifier", "event key modifier stop behavior")
+
+  trigger(a, "keyup", {keyCode: 13})
+  // see loadUrl defined above
+
+  t.end()
+})
+
+tape("test link with the same URL as the current one, when currentUrlFullReload set to true", function(t) {
+  var a = document.createElement("a")
+  var pjax = {
+    options: {
+      currentUrlFullReload: true
+    },
+    reload: function() {
+      t.pass("this.reload() was called correctly")
+    },
+    loadUrl: function() {
+      t.fail("loadUrl() was called wrongly")
+    }
+  }
+
+  t.plan(2)
+
+  attachLink.call(pjax, a)
+
+  a.href = window.location.href
+
+  trigger(a, "click")
+  t.equal(a.getAttribute(attr), "reload", "reload stop behavior")
+
+  t.end()
+})
diff --git a/tests/lib/proto/parse-element.js b/tests/lib/proto/parse-element.js
index 9d64e34..e58ef67 100644
--- a/tests/lib/proto/parse-element.js
+++ b/tests/lib/proto/parse-element.js
@@ -18,5 +18,10 @@ tape("test parse element prototype method", function(t) {
     parseElement.call(pjax, form)
   }, "<form> element can be parsed")
 
+  t.throws(function() {
+    var el = document.createElement("div")
+    parseElement.call(pjax, el)
+  }, "<div> element cannot be parsed")
+
   t.end()
 })
diff --git a/tests/lib/send-request.js b/tests/lib/send-request.js
index 8b86726..32d6de9 100644
--- a/tests/lib/send-request.js
+++ b/tests/lib/send-request.js
@@ -57,3 +57,81 @@ tape("request headers are sent properly", function(t) {
   })
 })
 
+tape("HTTP status codes other than 200 are handled properly", function(t) {
+  var url = "https://httpbin.org/status/400"
+
+  sendRequest(url, {}, function(responseText, request) {
+    t.equals(responseText, null, "responseText is null")
+    t.equals(request.status, 400, "HTTP status code is correct")
+
+    t.end()
+  })
+})
+
+tape.skip("XHR error is handled properly", function(t) {
+  var url = "https://encrypted.google.com/foobar"
+
+  sendRequest(url, {}, function(responseText) {
+    t.equals(responseText, null, "responseText is null")
+
+    t.end()
+  })
+})
+
+tape("POST body data is sent properly", function(t) {
+  var url = "https://httpbin.org/post"
+  var params = [{
+    name: "test",
+    value: "1"
+  }];
+  var options = {
+    requestOptions: {
+      requestMethod: "POST",
+      requestParams: params
+    }
+  }
+
+  sendRequest(url, options, function(responseText) {
+    var response = JSON.parse(responseText)
+
+    t.same(response.form[params[0].name], params[0].value, "requestParams were sent properly")
+    t.equals(response.headers["Content-Type"], "application/x-www-form-urlencoded", "Content-Type header was set properly")
+
+    t.end()
+  })
+})
+
+tape("GET query data is sent properly", function(t) {
+  var url = "https://httpbin.org/get"
+  var params = [{
+    name: "test",
+    value: "1"
+  }];
+  var options = {
+    requestOptions: {
+      requestParams: params
+    }
+  }
+
+  sendRequest(url, options, function(responseText) {
+    var response = JSON.parse(responseText)
+
+    t.same(response.args[params[0].name], params[0].value, "requestParams were sent properly")
+
+    t.end()
+  })
+})
+
+tape("XHR timeout is handled properly", function(t) {
+  var url = "https://httpbin.org/delay/5"
+  var options = {
+    timeout: 1000
+  }
+
+  sendRequest(url, options, function(responseText) {
+    t.equals(responseText, null, "responseText is null")
+
+    t.end()
+  })
+})
+
diff --git a/tests/lib/switch-selectors.js b/tests/lib/switch-selectors.js
index a999d9a..cea115d 100644
--- a/tests/lib/switch-selectors.js
+++ b/tests/lib/switch-selectors.js
@@ -42,3 +42,33 @@ tape("test switchesSelectors", function(t) {
 
   t.end()
 })
+
+tape("test switchesSelectors when number of elements don't match", function(t) {
+  var newTempDoc = document.implementation.createHTMLDocument()
+  var originalTempDoc = document.implementation.createHTMLDocument()
+
+  // a div container is used because swapping the containers
+  // will generate a new element, so things get weird
+  // using "body" generates a lot of testling cruft that I don't
+  // want so let's avoid that
+  var container = originalTempDoc.createElement("div")
+  container.innerHTML = "<p>Original text</p><span>No change</span>"
+  originalTempDoc.body.appendChild(container)
+
+  var container2 = newTempDoc.createElement("div")
+  container2.innerHTML = "<p>New text</p><p>More new text</p><span>New span</span>"
+  newTempDoc.body.appendChild(container2)
+
+  var switchSelectorsFn = switchesSelectors.bind(pjax,
+    {}, // switches
+    {}, // switchesOptions
+    ["p"], // selectors,
+    newTempDoc, // fromEl
+    originalTempDoc, // toEl,
+    {} // options
+  )
+
+  t.throws(switchSelectorsFn, null, "error was thrown properly since number of elements don't match")
+
+  t.end()
+})
diff --git a/tests/lib/util/extend.js b/tests/lib/util/extend.js
index f90468b..add707f 100644
--- a/tests/lib/util/extend.js
+++ b/tests/lib/util/extend.js
@@ -10,5 +10,8 @@ tape("test extend method", function(t) {
   t.notSame(obj, extended, "extended object doesn't have the same values as original object")
   t.notSame(obj.two, extended.two, "extended object value overwrites value from original object")
 
+  extended = extend(null)
+  t.equals(extended, null, "passing null returns null")
+
   t.end()
 })