internal: move make::expr_unit to make::ext::expr_unit

`expr_unit` is just a shortcut for a common expression, so it belongs in `make::ext`

crates/ide-assists/src/handlers/convert_from_to_tryfrom.rs

@@ -97,7 +97,7 @@ pub(crate) fn convert_from_to_tryfrom(acc: &mut Assists, ctx: &AssistContext<'_>
             );
 
             for r in return_exprs {
-                let t = r.expr().unwrap_or_else(make::expr_unit);
+                let t = r.expr().unwrap_or_else(make::ext::expr_unit);
                 ted::replace(t.syntax(), wrap_ok(t.clone()).syntax().clone_for_update());
             }
 

crates/ide-assists/src/handlers/extract_function.rs

@@ -1910,7 +1910,7 @@ fn make_body(ctx: &AssistContext<'_>, old_indent: IndentLevel, fun: &Function) -
     match &handler {
         FlowHandler::None => block,
         FlowHandler::Try { kind } => {
-            let block = with_default_tail_expr(block, make::expr_unit());
+            let block = with_default_tail_expr(block, make::ext::expr_unit());
             map_tail_expr(block, |tail_expr| {
                 let constructor = match kind {
                     TryKind::Option => "Some",
@@ -1924,7 +1924,7 @@ fn make_body(ctx: &AssistContext<'_>, old_indent: IndentLevel, fun: &Function) -
         FlowHandler::If { .. } => {
             let controlflow_continue = make::expr_call(
                 make::expr_path(make::path_from_text("ControlFlow::Continue")),
-                make::arg_list(iter::once(make::expr_unit())),
+                make::arg_list([make::ext::expr_unit()]),
             );
             with_tail_expr(block, controlflow_continue)
         }
@@ -2127,17 +2127,17 @@ fn make_rewritten_flow(handler: &FlowHandler, arg_expr: Option<ast::Expr>) -> Op
         FlowHandler::None | FlowHandler::Try { .. } => return None,
         FlowHandler::If { .. } => make::expr_call(
             make::expr_path(make::path_from_text("ControlFlow::Break")),
-            make::arg_list(iter::once(make::expr_unit())),
+            make::arg_list([make::ext::expr_unit()]),
         ),
         FlowHandler::IfOption { .. } => {
-            let expr = arg_expr.unwrap_or_else(|| make::expr_unit());
+            let expr = arg_expr.unwrap_or_else(make::ext::expr_unit);
-            let args = make::arg_list(iter::once(expr));
+            let args = make::arg_list([expr]);
             make::expr_call(make::expr_path(make::ext::ident_path("Some")), args)
         }
         FlowHandler::MatchOption { .. } => make::expr_path(make::ext::ident_path("None")),
         FlowHandler::MatchResult { .. } => {
-            let expr = arg_expr.unwrap_or_else(|| make::expr_unit());
+            let expr = arg_expr.unwrap_or_else(make::ext::expr_unit);
-            let args = make::arg_list(iter::once(expr));
+            let args = make::arg_list([expr]);
             make::expr_call(make::expr_path(make::ext::ident_path("Err")), args)
         }
     };

crates/ide-assists/src/handlers/remove_dbg.rs

@@ -102,7 +102,7 @@ fn compute_dbg_replacement(macro_expr: ast::MacroExpr) -> Option<(TextRange, Opt
                         };
                         (range, None)
                     },
-                    _ => (macro_call.syntax().text_range(), Some(make::expr_unit())),
+                    _ => (macro_call.syntax().text_range(), Some(make::ext::expr_unit())),
                 }
             }
         }

crates/ide-assists/src/handlers/replace_if_let_with_match.rs

@@ -179,7 +179,7 @@ fn make_else_arm(
             [(Either::Right(_), _)] => make::literal_pat("false").into(),
             _ => make::wildcard_pat().into(),
         };
-        (pattern, make::expr_unit())
+        (pattern, make::ext::expr_unit())
     };
     make::match_arm(iter::once(pattern), None, expr)
 }

crates/ide-assists/src/handlers/unwrap_block.rs

@@ -61,7 +61,7 @@ pub(crate) fn unwrap_block(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option
                 }
             }
             None => {
-                let empty_tuple = make::expr_unit();
+                let empty_tuple = make::ext::expr_unit();
                 make::let_stmt(pattern, ty, Some(empty_tuple)).to_string()
             }
         };

crates/syntax/src/ast/edit.rs

@@ -153,8 +153,9 @@ impl<N: AstNode + Clone> AstNodeEdit for N {}
 #[test]
 fn test_increase_indent() {
     let arm_list = {
-        let arm = make::match_arm(iter::once(make::wildcard_pat().into()), None, make::expr_unit());
+        let arm =
-        make::match_arm_list(vec![arm.clone(), arm])
+            make::match_arm(iter::once(make::wildcard_pat().into()), None, make::ext::expr_unit());
+        make::match_arm_list([arm.clone(), arm])
     };
     assert_eq!(
         arm_list.syntax().to_string(),

crates/syntax/src/ast/make.rs

@@ -63,6 +63,9 @@ pub mod ext {
         Some(expr)
     }
 
+    pub fn expr_unit() -> ast::Expr {
+        expr_tuple([]).into()
+    }
     pub fn expr_unreachable() -> ast::Expr {
         expr_from_text("unreachable!()")
     }
@@ -546,10 +549,6 @@ pub fn hacky_block_expr(
     ast_from_text(&format!("fn f() {buf}"))
 }
 
-pub fn expr_unit() -> ast::Expr {
-    expr_from_text("()")
-}
-
 pub fn expr_literal(text: &str) -> ast::Literal {
     assert_eq!(text.trim(), text);
     ast_from_text(&format!("fn f() {{ let _ = {text}; }}"))

crates/syntax/src/syntax_editor.rs

@@ -550,7 +550,7 @@ mod tests {
             None,
             None,
             make::param_list(None, []),
-            make::block_expr([], Some(make::expr_unit())),
+            make::block_expr([], Some(make::ext::expr_unit())),
             Some(make::ret_type(make::ty_unit())),
             false,
             false,