diff --git a/src/applications/differential/customfield/DifferentialAuditorsField.php b/src/applications/differential/customfield/DifferentialAuditorsField.php
--- a/src/applications/differential/customfield/DifferentialAuditorsField.php
+++ b/src/applications/differential/customfield/DifferentialAuditorsField.php
@@ -21,7 +21,9 @@
 
   public function setValueFromStorage($value) {
     try {
-      $this->setValue(phutil_json_decode($value));
+      if ($value != null) {
+         $this->setValue(phutil_json_decode($value));
+      }
     } catch (PhutilJSONParserException $ex) {
       $this->setValue(array());
     }
diff --git a/src/applications/differential/customfield/DifferentialBranchField.php b/src/applications/differential/customfield/DifferentialBranchField.php
--- a/src/applications/differential/customfield/DifferentialBranchField.php
+++ b/src/applications/differential/customfield/DifferentialBranchField.php
@@ -39,11 +39,11 @@
     $branch = $diff->getBranch();
     $bookmark = $diff->getBookmark();
 
-    if (strlen($branch) && strlen($bookmark)) {
+    if (phutil_nonempty_string($branch) && phutil_nonempty_string($bookmark)) {
       return pht('%s (bookmark) on %s (branch)', $bookmark, $branch);
-    } else if (strlen($bookmark)) {
+    } else if (phutil_nonempty_string($bookmark)) {
       return pht('%s (bookmark)', $bookmark);
-    } else if (strlen($branch)) {
+    } else if (phutil_nonempty_string($branch)) {
       $onto = $diff->loadTargetBranch();
       if (strlen($onto) && ($onto !== $branch)) {
         return pht(
diff --git a/src/applications/differential/editor/DifferentialTransactionEditor.php b/src/applications/differential/editor/DifferentialTransactionEditor.php
--- a/src/applications/differential/editor/DifferentialTransactionEditor.php
+++ b/src/applications/differential/editor/DifferentialTransactionEditor.php
@@ -218,21 +218,23 @@
 
           // No "$", to allow for branches like T123_demo.
           $match = null;
-          if (preg_match('/^T(\d+)/i', $branch, $match)) {
-            $task_id = $match[1];
-            $tasks = id(new ManiphestTaskQuery())
-              ->setViewer($this->getActor())
-              ->withIDs(array($task_id))
-              ->execute();
-            if ($tasks) {
-              $task = head($tasks);
-              $task_phid = $task->getPHID();
-
-              $results[] = id(new DifferentialTransaction())
-                ->setTransactionType($type_edge)
-                ->setMetadataValue('edge:type', $edge_ref_task)
-                ->setIgnoreOnNoEffect(true)
-                ->setNewValue(array('+' => array($task_phid => $task_phid)));
+          if ($branch !== null && $match !== null) {
+            if (preg_match('/^T(\d+)/i', $branch, $match)) {
+              $task_id = $match[1];
+              $tasks = id(new ManiphestTaskQuery())
+                ->setViewer($this->getActor())
+                ->withIDs(array($task_id))
+                ->execute();
+              if ($tasks) {
+                $task = head($tasks);
+                $task_phid = $task->getPHID();
+
+                $results[] = id(new DifferentialTransaction())
+                  ->setTransactionType($type_edge)
+                  ->setMetadataValue('edge:type', $edge_ref_task)
+                  ->setIgnoreOnNoEffect(true)
+                  ->setNewValue(array('+' => array($task_phid => $task_phid)));
+              }
             }
           }
         }
diff --git a/src/infrastructure/diff/view/PHUIDiffTableOfContentsItemView.php b/src/infrastructure/diff/view/PHUIDiffTableOfContentsItemView.php
--- a/src/infrastructure/diff/view/PHUIDiffTableOfContentsItemView.php
+++ b/src/infrastructure/diff/view/PHUIDiffTableOfContentsItemView.php
@@ -139,7 +139,7 @@
     $not_applicable = '-';
 
     $coverage = $this->getCoverage();
-    if (!strlen($coverage)) {
+    if (!phutil_nonempty_string($coverage)) {
       return $not_applicable;
     }
 
@@ -157,7 +157,7 @@
     $not_applicable = '-';
 
     $coverage = $this->getCoverage();
-    if (!strlen($coverage)) {
+    if (!phutil_nonempty_string($coverage)) {
       return $not_applicable;
     }
 
diff --git a/src/infrastructure/editor/PhabricatorEditorURIEngine.php b/src/infrastructure/editor/PhabricatorEditorURIEngine.php
--- a/src/infrastructure/editor/PhabricatorEditorURIEngine.php
+++ b/src/infrastructure/editor/PhabricatorEditorURIEngine.php
@@ -16,8 +16,10 @@
 
     $pattern = $viewer->getUserSetting(PhabricatorEditorSetting::SETTINGKEY);
 
-    if (!strlen(trim($pattern))) {
-      return null;
+    if (!phutil_nonempty_string($pattern)) {
+      if (!phutil_nonempty_string(trim($pattern))) {
+        return null;
+      }
     }
 
     $engine = id(new self())
diff --git a/src/infrastructure/javelin/markup.php b/src/infrastructure/javelin/markup.php
--- a/src/infrastructure/javelin/markup.php
+++ b/src/infrastructure/javelin/markup.php
@@ -74,7 +74,7 @@
   $body = array();
 
   $http_method = idx($attributes, 'method');
-  $is_post = (strcasecmp($http_method, 'POST') === 0);
+  $is_post = ($http_method !== null && strcasecmp($http_method, 'POST') === 0);
 
   $http_action = idx($attributes, 'action');