diff --git a/src/components/gfx/font_template.rs b/src/components/gfx/font_template.rs
index 2bd6a1270d2..12753da68a1 100644
--- a/src/components/gfx/font_template.rs
+++ b/src/components/gfx/font_template.rs
@@ -37,7 +37,7 @@ impl PartialEq for FontTemplateDescriptor {
 }
 
 /// This describes all the information needed to create
-/// font instance handles. It contains a unique 
+/// font instance handles. It contains a unique
 /// FontTemplateData structure that is platform specific.
 pub struct FontTemplate {
     identifier: String,
@@ -112,4 +112,4 @@ impl FontTemplate {
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/src/components/script/dom/htmlpreelement.rs b/src/components/script/dom/htmlpreelement.rs
index fa0e0a612b0..41b518271b5 100644
--- a/src/components/script/dom/htmlpreelement.rs
+++ b/src/components/script/dom/htmlpreelement.rs
@@ -20,7 +20,7 @@ pub struct HTMLPreElement {
 
 impl HTMLPreElementDerived for EventTarget {
     fn is_htmlpreelement(&self) -> bool {
-        self.type_id == NodeTargetTypeId(ElementNodeTypeId(HTMLPreElementTypeId)) 
+        self.type_id == NodeTargetTypeId(ElementNodeTypeId(HTMLPreElementTypeId))
     }
 }
 
diff --git a/src/components/util/opts.rs b/src/components/util/opts.rs
index 0fa3a79ed7c..bdd1d2d4347 100644
--- a/src/components/util/opts.rs
+++ b/src/components/util/opts.rs
@@ -45,7 +45,7 @@ pub struct Opts {
     /// cause it to produce output on that interval (`-p`).
     pub time_profiler_period: Option<f64>,
 
-    /// `None` to disable the memory profiler or `Some` with an interval in seconds to enable it 
+    /// `None` to disable the memory profiler or `Some` with an interval in seconds to enable it
     /// and cause it to produce output on that interval (`-m`).
     pub memory_profiler_period: Option<f64>,
 
diff --git a/src/etc/servo_gdb.py b/src/etc/servo_gdb.py
index 188f317fb70..fab29f3cfe6 100644
--- a/src/etc/servo_gdb.py
+++ b/src/etc/servo_gdb.py
@@ -12,7 +12,7 @@
 # To load these, you need to add something like the following
 # to your .gdbinit file.
 #python
-#import sys 
+#import sys
 #sys.path.insert(0, '/home/<path to git checkout>/servo/src/etc')
 #import servo_gdb
 #servo_gdb.register_printers(None)
diff --git a/src/etc/tidy.py b/src/etc/tidy.py
index ee7aab52f2e..c0cdb1eb433 100644
--- a/src/etc/tidy.py
+++ b/src/etc/tidy.py
@@ -27,6 +27,14 @@ def do_license_check(name, contents):
         report_error_name_no(name, 1, "incorrect license")
 
 
+def do_whitespace_check(name, contents):
+    for idx, line in enumerate(contents):
+        if line[-1] == "\n":
+            line = line[:-1]
+        if line.endswith(' '):
+            report_error_name_no(name, idx + 1, "trailing whitespace")
+
+
 exceptions = [
     # Upstream
     "src/support",
@@ -36,6 +44,7 @@ exceptions = [
 
     # Generated and upstream code combined with our own. Could use cleanup
     "src/components/script/dom/bindings/codegen",
+    "src/components/style/properties/mod.rs",
 ]
 
 
@@ -66,5 +75,6 @@ for path in file_names:
     with open(path, "r") as fp:
         lines = fp.readlines()
         do_license_check(path, "".join(lines))
+        do_whitespace_check(path, lines)
 
 sys.exit(err)