diff --git a/src/front/wgsl/lexer.rs b/src/front/wgsl/lexer.rs
index efd3bca3ca..af41041752 100644
--- a/src/front/wgsl/lexer.rs
+++ b/src/front/wgsl/lexer.rs
@@ -286,3 +286,51 @@ impl<'a> Lexer<'a> {
         source.len() - self.input.len()
     }
 }
+
+#[cfg(test)]
+fn sub_test(source: &str, expected_tokens: &[Token]) {
+    let mut lex = Lexer::new(source);
+    for &token in expected_tokens {
+        assert_eq!(lex.next(), token);
+    }
+    assert_eq!(lex.next(), Token::End);
+}
+
+#[test]
+fn test_tokens() {
+    sub_test("id123_OK", &[Token::Word("id123_OK")]);
+    sub_test("92No", &[Token::Number("92"), Token::Word("No")]);
+    sub_test(
+        "æNoø",
+        &[Token::Unknown('æ'), Token::Word("No"), Token::Unknown('ø')],
+    );
+    sub_test("No¾", &[Token::Word("No"), Token::Unknown('¾')]);
+    sub_test("No好", &[Token::Word("No"), Token::Unknown('好')]);
+    sub_test("\"\u{2}ПЀ\u{0}\"", &[Token::String("\u{2}ПЀ\u{0}")]); // https://github.com/gfx-rs/naga/issues/90
+}
+
+#[test]
+fn test_variable_decl() {
+    sub_test(
+        "[[ group(0 )]] var< uniform> texture:   texture_multisampled_2d <f32 >;",
+        &[
+            Token::DoubleParen('['),
+            Token::Word("group"),
+            Token::Paren('('),
+            Token::Number("0"),
+            Token::Paren(')'),
+            Token::DoubleParen(']'),
+            Token::Word("var"),
+            Token::Paren('<'),
+            Token::Word("uniform"),
+            Token::Paren('>'),
+            Token::Word("texture"),
+            Token::Separator(':'),
+            Token::Word("texture_multisampled_2d"),
+            Token::Paren('<'),
+            Token::Word("f32"),
+            Token::Paren('>'),
+            Token::Separator(';'),
+        ],
+    )
+}
diff --git a/src/front/wgsl/mod.rs b/src/front/wgsl/mod.rs
index 17f3fe1d29..102ea0ca65 100644
--- a/src/front/wgsl/mod.rs
+++ b/src/front/wgsl/mod.rs
@@ -1830,44 +1830,8 @@ pub fn parse_str(source: &str) -> Result<crate::Module, ParseError> {
     Parser::new().parse(source)
 }
 
-#[cfg(test)]
-mod tests {
-    use crate::front::wgsl::{Lexer, Token};
-
-    #[test]
-    fn check_constant_type_scalar_ok() {
-        let wgsl = "const a : i32 = 2;";
-        assert!(super::parse_str(wgsl).is_ok());
-    }
-
-    #[test]
-    fn check_constant_type_scalar_err() {
-        let wgsl = "const a : i32 = 2.0;";
-        assert!(super::parse_str(wgsl).is_err());
-    }
-
-    #[test]
-    fn check_lexer() {
-        use Token::{End, Number, String, Unknown, Word};
-        let data = vec![
-            ("id123_OK", vec![Word("id123_OK"), End]),
-            ("92No", vec![Number("92"), Word("No"), End]),
-            ("æNoø", vec![Unknown('æ'), Word("No"), Unknown('ø'), End]),
-            ("No¾", vec![Word("No"), Unknown('¾'), End]),
-            ("No好", vec![Word("No"), Unknown('好'), End]),
-            ("\"\u{2}ПЀ\u{0}\"", vec![String("\u{2}ПЀ\u{0}"), End]), // https://github.com/gfx-rs/naga/issues/90
-        ];
-        for (x, expected) in data {
-            let mut lex = Lexer::new(x);
-            let mut results = vec![];
-            loop {
-                let result = lex.next();
-                results.push(result);
-                if result == Token::End {
-                    break;
-                }
-            }
-            assert_eq!(expected, results);
-        }
-    }
+#[test]
+fn parse_types() {
+    assert!(parse_str("const a : i32 = 2;").is_ok());
+    assert!(parse_str("const a : i32 = 2.0;").is_err());
 }