diff --git a/tests/src/App/CMakeLists.txt b/tests/src/App/CMakeLists.txt
index 7cbf44839d..0b4eaed5eb 100644
--- a/tests/src/App/CMakeLists.txt
+++ b/tests/src/App/CMakeLists.txt
@@ -2,6 +2,7 @@ target_sources(
     Tests_run
         PRIVATE
             ${CMAKE_CURRENT_SOURCE_DIR}/Branding.cpp
+            ${CMAKE_CURRENT_SOURCE_DIR}/Expression.cpp
             ${CMAKE_CURRENT_SOURCE_DIR}/License.cpp
             ${CMAKE_CURRENT_SOURCE_DIR}/Metadata.cpp
 )
diff --git a/tests/src/App/Expression.cpp b/tests/src/App/Expression.cpp
new file mode 100644
index 0000000000..2072796c32
--- /dev/null
+++ b/tests/src/App/Expression.cpp
@@ -0,0 +1,25 @@
+#include "gtest/gtest.h"
+
+#include "App/ExpressionTokenizer.h"
+
+TEST(Expression, tokenize)
+{
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString::fromUtf8(""), 10), QString());
+    // 0.0000 deg-
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString::fromUtf8("0.00000 \xC2\xB0-"), 10), QString());
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString::fromUtf8("0.00000 \xC2\xB0-s"), 11), QString("s"));
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString::fromUtf8("0.00000 \xC2\xB0-ss"), 12), QString("ss"));
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString::fromUtf8("0.00000 deg"), 5), QString());
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString::fromUtf8("0.00000 deg"), 11), QString("deg"));
+}
+
+TEST(Expression, tokenizePi)
+{
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString("p"), 1), QString("p"));
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString("pi"), 2), QString());
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString("pi "), 3), QString());
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString("pi r"), 4), QString("r"));
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString("pi ra"), 5), QString("ra"));
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString("pi rad"), 6), QString("rad"));
+    EXPECT_EQ(App::ExpressionTokenizer().perform(QString("pi rad"), 2), QString());
+}