From b3de0033027c051fa1eee3e728e208b67d5ac6f5 Mon Sep 17 00:00:00 2001
From: zakuro <z@kuro.red>
Date: Sun, 3 Jan 2021 00:36:31 +0900
Subject: [PATCH] fmt: fix broken formatting in fn struct fields (#7794)

---
 vlib/v/fmt/fmt.v                              |  2 +-
 vlib/v/fmt/tests/struct_fn_fields_expected.vv |  6 ++++++
 vlib/v/fmt/tests/struct_fn_fields_input.vv    |  6 ++++++
 vlib/v/table/types.v                          | 10 ++++++++--
 4 files changed, 21 insertions(+), 3 deletions(-)
 create mode 100644 vlib/v/fmt/tests/struct_fn_fields_expected.vv
 create mode 100644 vlib/v/fmt/tests/struct_fn_fields_input.vv

diff --git a/vlib/v/fmt/fmt.v b/vlib/v/fmt/fmt.v
index e589bc763a..29a0117911 100644
--- a/vlib/v/fmt/fmt.v
+++ b/vlib/v/fmt/fmt.v
@@ -622,7 +622,7 @@ pub fn (mut f Fmt) struct_decl(node ast.StructDecl) {
 			max = comments_len + field.name.len
 		}
 		mut ft := f.no_cur_mod(f.table.type_to_str(field.typ))
-		if !ft.contains('C.') && !ft.contains('JS.') {
+		if !ft.contains('C.') && !ft.contains('JS.') && !ft.contains('fn (') {
 			ft = f.short_module(ft)
 		}
 		field_types << ft
diff --git a/vlib/v/fmt/tests/struct_fn_fields_expected.vv b/vlib/v/fmt/tests/struct_fn_fields_expected.vv
new file mode 100644
index 0000000000..a01e87a991
--- /dev/null
+++ b/vlib/v/fmt/tests/struct_fn_fields_expected.vv
@@ -0,0 +1,6 @@
+import v.ast
+
+struct Data {
+	a fn (string, voidptr) bool
+	b fn (ast.Stmt, voidptr) bool
+}
diff --git a/vlib/v/fmt/tests/struct_fn_fields_input.vv b/vlib/v/fmt/tests/struct_fn_fields_input.vv
new file mode 100644
index 0000000000..7e5d5196a5
--- /dev/null
+++ b/vlib/v/fmt/tests/struct_fn_fields_input.vv
@@ -0,0 +1,6 @@
+import v.ast
+
+struct Data {
+	a fn (s string, f voidptr) bool
+	b fn (stmt ast.Stmt, f voidptr) bool
+}
diff --git a/vlib/v/table/types.v b/vlib/v/table/types.v
index 984b1841e7..5ff7657902 100644
--- a/vlib/v/table/types.v
+++ b/vlib/v/table/types.v
@@ -744,11 +744,17 @@ pub fn (table &Table) type_to_str_using_aliases(t Type, import_aliases map[strin
 			}
 		}
 		.function {
+			info := sym.info as FnType
 			if !table.is_fmt {
-				info := sym.info as FnType
 				res = table.fn_signature(info.func, type_only: true)
 			} else {
-				res = table.shorten_user_defined_typenames(res, import_aliases)
+				if res.starts_with('fn (') {
+					// fn foo ()
+					res = table.fn_signature(info.func, type_only: true)
+				} else {
+					// FnFoo
+					res = table.shorten_user_defined_typenames(res, import_aliases)
+				}
 			}
 		}
 		.map {