diff --git a/crates/hir_def/src/macro_expansion_tests/builtin.rs b/crates/hir_def/src/macro_expansion_tests/builtin.rs
index 1b25caa0ff1b..6982116522c6 100644
--- a/crates/hir_def/src/macro_expansion_tests/builtin.rs
+++ b/crates/hir_def/src/macro_expansion_tests/builtin.rs
@@ -270,3 +270,63 @@ unsafe {
 "##]],
     );
 }
+
+#[test]
+fn test_include_bytes_expand() {
+    check(
+        r#"
+#[rustc_builtin_macro]
+macro_rules! include_bytes {
+    ($file:expr) => {{ /* compiler built-in */ }};
+    ($file:expr,) => {{ /* compiler built-in */ }};
+}
+
+fn main() { include_bytes("foo"); }
+"#,
+        expect![[r##"
+#[rustc_builtin_macro]
+macro_rules! include_bytes {
+    ($file:expr) => {{ /* compiler built-in */ }};
+    ($file:expr,) => {{ /* compiler built-in */ }};
+}
+
+fn main() { include_bytes("foo"); }
+"##]],
+    );
+}
+
+#[test]
+fn test_concat_expand() {
+    check(
+        r##"
+#[rustc_builtin_macro]
+macro_rules! concat {}
+
+fn main() { concat!("foo", "r", 0, r#"bar"#, "\n", false); }
+"##,
+        expect![[r##"
+#[rustc_builtin_macro]
+macro_rules! concat {}
+
+fn main() { "foor0bar\nfalse"; }
+"##]],
+    );
+}
+
+#[test]
+fn test_concat_idents_expand() {
+    check(
+        r##"
+#[rustc_builtin_macro]
+macro_rules! concat_idents {}
+
+fn main() { concat_idents!(foo, bar); }
+"##,
+        expect![[r##"
+#[rustc_builtin_macro]
+macro_rules! concat_idents {}
+
+fn main() { foobar; }
+"##]],
+    );
+}
diff --git a/crates/hir_expand/src/builtin_macro.rs b/crates/hir_expand/src/builtin_macro.rs
index f988ffff09ee..4b801eb2a154 100644
--- a/crates/hir_expand/src/builtin_macro.rs
+++ b/crates/hir_expand/src/builtin_macro.rs
@@ -565,146 +565,3 @@ fn option_env_expand(
 
     ExpandResult::ok(Some(ExpandedEager::new(expanded)))
 }
-
-#[cfg(test)]
-mod tests {
-    use std::sync::Arc;
-
-    use base_db::{fixture::WithFixture, SourceDatabase};
-    use expect_test::{expect, Expect};
-    use syntax::ast::HasName;
-
-    use crate::{
-        name::AsName, test_db::TestDB, AstNode, EagerCallInfo, ExpandTo, MacroCallId,
-        MacroCallKind, MacroCallLoc,
-    };
-
-    use super::*;
-
-    fn expand_builtin_macro(ra_fixture: &str) -> String {
-        let (db, file_id) = TestDB::with_single_file(ra_fixture);
-        let parsed = db.parse(file_id);
-        let mut macro_rules: Vec<_> =
-            parsed.syntax_node().descendants().filter_map(ast::MacroRules::cast).collect();
-        let mut macro_calls: Vec<_> =
-            parsed.syntax_node().descendants().filter_map(ast::MacroCall::cast).collect();
-
-        let ast_id_map = db.ast_id_map(file_id.into());
-
-        assert_eq!(macro_rules.len(), 1, "test must contain exactly 1 `macro_rules!`");
-        assert_eq!(macro_calls.len(), 1, "test must contain exactly 1 macro call");
-        let macro_rules = ast::Macro::from(macro_rules.pop().unwrap());
-        let macro_call = macro_calls.pop().unwrap();
-
-        let expander = find_by_name(&macro_rules.name().unwrap().as_name()).unwrap();
-        let ast_id = AstId::new(file_id.into(), ast_id_map.ast_id(&macro_rules));
-
-        let krate = CrateId(0);
-        let file_id = match expander {
-            Either::Left(expander) => {
-                // the first one should be a macro_rules
-                let def = MacroDefId {
-                    krate: CrateId(0),
-                    kind: MacroDefKind::BuiltIn(expander, ast_id),
-                    local_inner: false,
-                };
-
-                let loc = MacroCallLoc {
-                    def,
-                    krate,
-                    eager: None,
-                    kind: MacroCallKind::FnLike {
-                        ast_id: AstId::new(file_id.into(), ast_id_map.ast_id(&macro_call)),
-                        expand_to: ExpandTo::Expr,
-                    },
-                };
-
-                let id: MacroCallId = db.intern_macro(loc);
-                id.as_file()
-            }
-            Either::Right(expander) => {
-                // the first one should be a macro_rules
-                let def = MacroDefId {
-                    krate,
-                    kind: MacroDefKind::BuiltInEager(expander, ast_id),
-                    local_inner: false,
-                };
-
-                let args = macro_call.token_tree().unwrap();
-                let parsed_args = mbe::syntax_node_to_token_tree(args.syntax()).0;
-                let call_id = AstId::new(file_id.into(), ast_id_map.ast_id(&macro_call));
-
-                let arg_id = db.intern_macro(MacroCallLoc {
-                    def,
-                    krate,
-                    eager: Some(EagerCallInfo {
-                        arg_or_expansion: Arc::new(parsed_args.clone()),
-                        included_file: None,
-                    }),
-                    kind: MacroCallKind::FnLike { ast_id: call_id, expand_to: ExpandTo::Expr },
-                });
-
-                let expanded = expander.expand(&db, arg_id, &parsed_args).value.unwrap();
-                let expand_to = crate::ExpandTo::from_call_site(&macro_call);
-                let loc = MacroCallLoc {
-                    def,
-                    krate,
-                    eager: Some(EagerCallInfo {
-                        arg_or_expansion: Arc::new(expanded.subtree),
-                        included_file: expanded.included_file,
-                    }),
-                    kind: MacroCallKind::FnLike { ast_id: call_id, expand_to },
-                };
-
-                let id: MacroCallId = db.intern_macro(loc);
-                id.as_file()
-            }
-        };
-
-        db.parse_or_expand(file_id).unwrap().to_string()
-    }
-
-    fn check_expansion(ra_fixture: &str, expect: Expect) {
-        let expansion = expand_builtin_macro(ra_fixture);
-        expect.assert_eq(&expansion);
-    }
-
-    #[test]
-    fn test_include_bytes_expand() {
-        check_expansion(
-            r#"
-            #[rustc_builtin_macro]
-            macro_rules! include_bytes {
-                ($file:expr) => {{ /* compiler built-in */ }};
-                ($file:expr,) => {{ /* compiler built-in */ }};
-            }
-            include_bytes("foo");
-            "#,
-            expect![[r#"b"""#]],
-        );
-    }
-
-    #[test]
-    fn test_concat_expand() {
-        check_expansion(
-            r##"
-            #[rustc_builtin_macro]
-            macro_rules! concat {}
-            concat!("foo", "r", 0, r#"bar"#, "\n", false);
-            "##,
-            expect![[r#""foor0bar\nfalse""#]],
-        );
-    }
-
-    #[test]
-    fn test_concat_idents_expand() {
-        check_expansion(
-            r##"
-            #[rustc_builtin_macro]
-            macro_rules! concat_idents {}
-            concat_idents!(foo, bar);
-            "##,
-            expect![[r#"foobar"#]],
-        );
-    }
-}