diff --git a/packages/material-ui-system/src/shadows.test.js b/packages/material-ui-system/src/shadows.test.js
deleted file mode 100644
index 512f501ed5c922..00000000000000
--- a/packages/material-ui-system/src/shadows.test.js
+++ /dev/null
@@ -1,30 +0,0 @@
-import boxShadow from './shadows';
-import { assert } from 'chai';
-
-describe('shadows', () => {
-  it('should support array theme value', () => {
-    const output = boxShadow({
-      theme: {
-        shadows: ['none', '0px 1px 3px 0px rgba(0, 0, 0, 0.2)'],
-      },
-      boxShadow: 1,
-    });
-
-    assert.deepEqual(output, {
-      boxShadow: '0px 1px 3px 0px rgba(0, 0, 0, 0.2)',
-    });
-  });
-
-  it('should support CSS string value', () => {
-    const output = boxShadow({
-      theme: {
-        shadows: ['none'],
-      },
-      boxShadow: '0px 1px 3px 0px rgba(0, 0, 0, 0.2)',
-    });
-
-    assert.deepEqual(output, {
-      boxShadow: '0px 1px 3px 0px rgba(0, 0, 0, 0.2)',
-    });
-  });
-});
diff --git a/packages/material-ui-system/src/style.test.js b/packages/material-ui-system/src/style.test.js
index 12f845a29a546e..c027d413ca51bf 100644
--- a/packages/material-ui-system/src/style.test.js
+++ b/packages/material-ui-system/src/style.test.js
@@ -63,6 +63,37 @@ describe('style', () => {
     // });
   });
 
+  const boxShadow = style({
+    prop: 'boxShadow',
+    themeKey: 'shadows',
+  });
+
+  it('should support array theme value', () => {
+    const output = boxShadow({
+      theme: {
+        shadows: ['none', '0px 1px 3px 0px rgba(0, 0, 0, 0.2)'],
+      },
+      boxShadow: 1,
+    });
+
+    assert.deepEqual(output, {
+      boxShadow: '0px 1px 3px 0px rgba(0, 0, 0, 0.2)',
+    });
+  });
+
+  it('should fallback to value if theme is an array', () => {
+    const output = boxShadow({
+      theme: {
+        shadows: ['none'],
+      },
+      boxShadow: '0px 1px 3px 0px rgba(0, 0, 0, 0.2)',
+    });
+
+    assert.deepEqual(output, {
+      boxShadow: '0px 1px 3px 0px rgba(0, 0, 0, 0.2)',
+    });
+  });
+
   const border = style({
     prop: 'border',
     themeKey: 'borders',