From 882c74dfcf974d4129b268ca1aef4de28cd6cc4e Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <n.nethercote@gmail.com>
Date: Tue, 29 Apr 2025 16:52:17 +1000
Subject: [PATCH 1/7] Remove fake `BoxMarker`s.

They don't appear to do anything -- no test output is affected -- and no
other pretty-printing code looks like this.
---
 compiler/rustc_ast_pretty/src/pprust/state/expr.rs | 11 +----------
 compiler/rustc_hir_pretty/src/lib.rs               |  9 ---------
 2 files changed, 1 insertion(+), 19 deletions(-)

diff --git a/compiler/rustc_ast_pretty/src/pprust/state/expr.rs b/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
index 38cadc77b7771..abcbb88aab2d9 100644
--- a/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
+++ b/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
@@ -13,7 +13,7 @@ use rustc_ast::{
 
 use crate::pp::Breaks::Inconsistent;
 use crate::pprust::state::fixup::FixupContext;
-use crate::pprust::state::{AnnNode, BoxMarker, INDENT_UNIT, PrintState, State};
+use crate::pprust::state::{AnnNode, INDENT_UNIT, PrintState, State};
 
 impl<'a> State<'a> {
     fn print_else(&mut self, els: Option<&ast::Expr>) {
@@ -542,15 +542,6 @@ impl<'a> State<'a> {
                 self.print_fn_params_and_ret(fn_decl, true);
                 self.space();
                 self.print_expr(body, FixupContext::default());
-                // FIXME(nnethercote): Bogus. Reduce visibility of `ended` once it's fixed.
-                let fake_ib = BoxMarker;
-                self.end(fake_ib);
-
-                // A box will be closed by print_expr, but we didn't want an overall
-                // wrapper so we closed the corresponding opening. so create an
-                // empty box to satisfy the close.
-                // FIXME(nnethercote): Bogus.
-                let _ib = self.ibox(0);
             }
             ast::ExprKind::Block(blk, opt_label) => {
                 if let Some(label) = opt_label {
diff --git a/compiler/rustc_hir_pretty/src/lib.rs b/compiler/rustc_hir_pretty/src/lib.rs
index 15e997aebcb8f..4035de9571586 100644
--- a/compiler/rustc_hir_pretty/src/lib.rs
+++ b/compiler/rustc_hir_pretty/src/lib.rs
@@ -1572,15 +1572,6 @@ impl<'a> State<'a> {
 
                 // This is a bare expression.
                 self.ann.nested(self, Nested::Body(body));
-                // FIXME(nnethercote): this is bogus
-                let fake_ib = BoxMarker;
-                self.end(fake_ib);
-
-                // A box will be closed by `print_expr`, but we didn't want an overall
-                // wrapper so we closed the corresponding opening. so create an
-                // empty box to satisfy the close.
-                // FIXME(nnethercote): this is bogus, and `print_expr` is missing
-                let _ib = self.ibox(0);
             }
             hir::ExprKind::Block(blk, opt_label) => {
                 if let Some(label) = opt_label {

From 3896ad0acd53fa62cab711d20af8dec1f3e944a1 Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <n.nethercote@gmail.com>
Date: Tue, 29 Apr 2025 19:59:36 +1000
Subject: [PATCH 2/7] Remove opaque type printing.

As far as I can tell, this code is not actually reachable.
---
 compiler/rustc_hir_pretty/src/lib.rs | 10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)

diff --git a/compiler/rustc_hir_pretty/src/lib.rs b/compiler/rustc_hir_pretty/src/lib.rs
index 4035de9571586..f4076e1114b32 100644
--- a/compiler/rustc_hir_pretty/src/lib.rs
+++ b/compiler/rustc_hir_pretty/src/lib.rs
@@ -183,7 +183,7 @@ impl<'a> State<'a> {
             Node::Ty(a) => self.print_type(a),
             Node::AssocItemConstraint(a) => self.print_assoc_item_constraint(a),
             Node::TraitRef(a) => self.print_trait_ref(a),
-            Node::OpaqueTy(o) => self.print_opaque_ty(o),
+            Node::OpaqueTy(_) => panic!("cannot print Node::OpaqueTy"),
             Node::Pat(a) => self.print_pat(a),
             Node::TyPat(a) => self.print_ty_pat(a),
             Node::PatField(a) => self.print_patfield(a),
@@ -764,14 +764,6 @@ impl<'a> State<'a> {
         self.print_path(t.path, false);
     }
 
-    fn print_opaque_ty(&mut self, o: &hir::OpaqueTy<'_>) {
-        // FIXME(nnethercote): `cb` and `ib` are unclosed
-        let (_cb, _ib) = self.head("opaque");
-        self.word("{");
-        self.print_bounds("impl", o.bounds);
-        self.word("}");
-    }
-
     fn print_formal_generic_params(&mut self, generic_params: &[hir::GenericParam<'_>]) {
         if !generic_params.is_empty() {
             self.word("for");

From 760cf8d3afd446e9a5f3dc1af006548a0da5686c Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <n.nethercote@gmail.com>
Date: Tue, 29 Apr 2025 20:07:10 +1000
Subject: [PATCH 3/7] Fix hir pretty-printing of `global_asm!`.

One of the boxes isn't closed, and this causes everything after it to be
over-indented.
---
 compiler/rustc_hir_pretty/src/lib.rs        | 7 ++++---
 tests/ui/unpretty/exhaustive-asm.hir.stdout | 3 ++-
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/compiler/rustc_hir_pretty/src/lib.rs b/compiler/rustc_hir_pretty/src/lib.rs
index f4076e1114b32..d119402222bb0 100644
--- a/compiler/rustc_hir_pretty/src/lib.rs
+++ b/compiler/rustc_hir_pretty/src/lib.rs
@@ -654,10 +654,11 @@ impl<'a> State<'a> {
                 self.bclose(item.span, cb);
             }
             hir::ItemKind::GlobalAsm { asm, .. } => {
-                // FIXME(nnethercote): `ib` is unclosed
-                let (cb, _ib) = self.head("global_asm!");
+                let (cb, ib) = self.head("global_asm!");
                 self.print_inline_asm(asm);
-                self.end(cb)
+                self.word(";");
+                self.end(cb);
+                self.end(ib);
             }
             hir::ItemKind::TyAlias(ident, ty, generics) => {
                 let (cb, ib) = self.head("type");
diff --git a/tests/ui/unpretty/exhaustive-asm.hir.stdout b/tests/ui/unpretty/exhaustive-asm.hir.stdout
index 5a642dff6f2e4..810db69bff161 100644
--- a/tests/ui/unpretty/exhaustive-asm.hir.stdout
+++ b/tests/ui/unpretty/exhaustive-asm.hir.stdout
@@ -27,5 +27,6 @@ mod expressions {
 mod items {
     /// ItemKind::GlobalAsm
     mod item_global_asm {/// ItemKind::GlobalAsm
-        global_asm! (".globl my_asm_func") }
+        global_asm! (".globl my_asm_func");
     }
+}

From aa7bb1c2f5a8d8e8b709421189186e8e5e8b64f9 Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <n.nethercote@gmail.com>
Date: Tue, 29 Apr 2025 20:17:29 +1000
Subject: [PATCH 4/7] Enable `BoxMarker` drop checking.

All the box open/close issues have been fixed.
---
 compiler/rustc_ast_pretty/src/pp.rs | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/compiler/rustc_ast_pretty/src/pp.rs b/compiler/rustc_ast_pretty/src/pp.rs
index 142c80b8e39e5..8a0dbadf18cdf 100644
--- a/compiler/rustc_ast_pretty/src/pp.rs
+++ b/compiler/rustc_ast_pretty/src/pp.rs
@@ -244,9 +244,6 @@ struct BufEntry {
 // forgotten will trigger a panic in `drop`. (Closing a box more than once
 // isn't possible because `BoxMarker` doesn't implement `Copy` or `Clone`.)
 //
-// FIXME(nnethercote): the panic in `drop` is currently disabled because a few
-// places fail to close their boxes. It can be enabled once they are fixed.
-//
 // Note: it would be better to make open/close mismatching impossible and avoid
 // the need for this marker type altogether by having functions like
 // `with_ibox` that open a box, call a closure, and then close the box. That
@@ -261,8 +258,7 @@ impl !Copy for BoxMarker {}
 
 impl Drop for BoxMarker {
     fn drop(&mut self) {
-        // FIXME(nnethercote): enable once the bad cases are fixed
-        //panic!("BoxMarker not ended with `Printer::end()`");
+        panic!("BoxMarker not ended with `Printer::end()`");
     }
 }
 

From e1a177bbba2b1297c33e2838f8b2b72ab5f62ecf Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <n.nethercote@gmail.com>
Date: Wed, 30 Apr 2025 10:08:01 +1000
Subject: [PATCH 5/7] Improve hir pretty-printing of attributes.

---
 compiler/rustc_hir_pretty/src/lib.rs          |  1 +
 tests/pretty/hir-delegation.pp                |  3 +-
 .../attrs/automatically_derived.rs            |  2 +-
 tests/rustdoc-json/attrs/export_name_2021.rs  |  2 +-
 tests/rustdoc-json/attrs/export_name_2024.rs  |  2 +-
 tests/rustdoc-json/attrs/must_use.rs          |  4 +-
 tests/rustdoc-json/attrs/no_mangle_2021.rs    |  2 +-
 tests/rustdoc-json/attrs/no_mangle_2024.rs    |  2 +-
 tests/rustdoc-json/attrs/non_exhaustive.rs    |  6 +--
 tests/rustdoc-json/keyword_private.rs         |  4 +-
 .../ui-fulldeps/stable-mir/check_attribute.rs |  4 +-
 tests/ui/unpretty/exhaustive.hir.stdout       | 38 ++++++++++++++++---
 12 files changed, 49 insertions(+), 21 deletions(-)

diff --git a/compiler/rustc_hir_pretty/src/lib.rs b/compiler/rustc_hir_pretty/src/lib.rs
index d119402222bb0..1e260b2dda456 100644
--- a/compiler/rustc_hir_pretty/src/lib.rs
+++ b/compiler/rustc_hir_pretty/src/lib.rs
@@ -110,6 +110,7 @@ impl<'a> State<'a> {
                 }
                 self.print_attr_item(&unparsed, unparsed.span);
                 self.word("]");
+                self.hardbreak()
             }
             hir::Attribute::Parsed(AttributeKind::DocComment { style, kind, comment, .. }) => {
                 self.word(rustc_ast_pretty::pprust::state::doc_comment_to_string(
diff --git a/tests/pretty/hir-delegation.pp b/tests/pretty/hir-delegation.pp
index 872a6a45aede1..e452cee636597 100644
--- a/tests/pretty/hir-delegation.pp
+++ b/tests/pretty/hir-delegation.pp
@@ -2,7 +2,8 @@
 //@ pretty-mode:hir
 //@ pp-exact:hir-delegation.pp
 
-#![allow(incomplete_features)]#![feature(fn_delegation)]
+#![allow(incomplete_features)]
+#![feature(fn_delegation)]
 #[prelude_import]
 use ::std::prelude::rust_2015::*;
 #[macro_use]
diff --git a/tests/rustdoc-json/attrs/automatically_derived.rs b/tests/rustdoc-json/attrs/automatically_derived.rs
index 4e1ab3d145e5d..6c90d6386499c 100644
--- a/tests/rustdoc-json/attrs/automatically_derived.rs
+++ b/tests/rustdoc-json/attrs/automatically_derived.rs
@@ -9,5 +9,5 @@ impl Default for Manual {
     }
 }
 
-//@ is '$.index[?(@.inner.impl.for.resolved_path.path == "Derive" && @.inner.impl.trait.path == "Default")].attrs' '["#[automatically_derived]"]'
+//@ is '$.index[?(@.inner.impl.for.resolved_path.path == "Derive" && @.inner.impl.trait.path == "Default")].attrs' '["#[automatically_derived]\n"]'
 //@ is '$.index[?(@.inner.impl.for.resolved_path.path == "Manual" && @.inner.impl.trait.path == "Default")].attrs' '[]'
diff --git a/tests/rustdoc-json/attrs/export_name_2021.rs b/tests/rustdoc-json/attrs/export_name_2021.rs
index 254e9f6ef5bfd..4e6526419bdbf 100644
--- a/tests/rustdoc-json/attrs/export_name_2021.rs
+++ b/tests/rustdoc-json/attrs/export_name_2021.rs
@@ -1,6 +1,6 @@
 //@ edition: 2021
 #![no_std]
 
-//@ is "$.index[?(@.name=='example')].attrs" '["#[export_name = \"altered\"]"]'
+//@ is "$.index[?(@.name=='example')].attrs" '["#[export_name = \"altered\"]\n"]'
 #[export_name = "altered"]
 pub extern "C" fn example() {}
diff --git a/tests/rustdoc-json/attrs/export_name_2024.rs b/tests/rustdoc-json/attrs/export_name_2024.rs
index 8129c109306c0..f6a2a92b5bcd3 100644
--- a/tests/rustdoc-json/attrs/export_name_2024.rs
+++ b/tests/rustdoc-json/attrs/export_name_2024.rs
@@ -4,6 +4,6 @@
 // The representation of `#[unsafe(export_name = ..)]` in rustdoc in edition 2024
 // is still `#[export_name = ..]` without the `unsafe` attribute wrapper.
 
-//@ is "$.index[?(@.name=='example')].attrs" '["#[export_name = \"altered\"]"]'
+//@ is "$.index[?(@.name=='example')].attrs" '["#[export_name = \"altered\"]\n"]'
 #[unsafe(export_name = "altered")]
 pub extern "C" fn example() {}
diff --git a/tests/rustdoc-json/attrs/must_use.rs b/tests/rustdoc-json/attrs/must_use.rs
index 64df8e5f509ff..20696dce7121e 100644
--- a/tests/rustdoc-json/attrs/must_use.rs
+++ b/tests/rustdoc-json/attrs/must_use.rs
@@ -1,9 +1,9 @@
 #![no_std]
 
-//@ is "$.index[?(@.name=='example')].attrs" '["#[must_use]"]'
+//@ is "$.index[?(@.name=='example')].attrs" '["#[must_use]\n"]'
 #[must_use]
 pub fn example() -> impl Iterator<Item = i64> {}
 
-//@ is "$.index[?(@.name=='explicit_message')].attrs" '["#[must_use = \"does nothing if you do not use it\"]"]'
+//@ is "$.index[?(@.name=='explicit_message')].attrs" '["#[must_use = \"does nothing if you do not use it\"]\n"]'
 #[must_use = "does nothing if you do not use it"]
 pub fn explicit_message() -> impl Iterator<Item = i64> {}
diff --git a/tests/rustdoc-json/attrs/no_mangle_2021.rs b/tests/rustdoc-json/attrs/no_mangle_2021.rs
index 588be7256db5a..10a372572ae57 100644
--- a/tests/rustdoc-json/attrs/no_mangle_2021.rs
+++ b/tests/rustdoc-json/attrs/no_mangle_2021.rs
@@ -1,6 +1,6 @@
 //@ edition: 2021
 #![no_std]
 
-//@ is "$.index[?(@.name=='example')].attrs" '["#[no_mangle]"]'
+//@ is "$.index[?(@.name=='example')].attrs" '["#[no_mangle]\n"]'
 #[no_mangle]
 pub extern "C" fn example() {}
diff --git a/tests/rustdoc-json/attrs/no_mangle_2024.rs b/tests/rustdoc-json/attrs/no_mangle_2024.rs
index 0d500e20e6c50..8f3a14cbecbf7 100644
--- a/tests/rustdoc-json/attrs/no_mangle_2024.rs
+++ b/tests/rustdoc-json/attrs/no_mangle_2024.rs
@@ -4,6 +4,6 @@
 // The representation of `#[unsafe(no_mangle)]` in rustdoc in edition 2024
 // is still `#[no_mangle]` without the `unsafe` attribute wrapper.
 
-//@ is "$.index[?(@.name=='example')].attrs" '["#[no_mangle]"]'
+//@ is "$.index[?(@.name=='example')].attrs" '["#[no_mangle]\n"]'
 #[unsafe(no_mangle)]
 pub extern "C" fn example() {}
diff --git a/tests/rustdoc-json/attrs/non_exhaustive.rs b/tests/rustdoc-json/attrs/non_exhaustive.rs
index b95f1a8171fd4..3064b86422d11 100644
--- a/tests/rustdoc-json/attrs/non_exhaustive.rs
+++ b/tests/rustdoc-json/attrs/non_exhaustive.rs
@@ -1,18 +1,18 @@
 #![no_std]
 
-//@ is "$.index[?(@.name=='MyEnum')].attrs" '["#[non_exhaustive]"]'
+//@ is "$.index[?(@.name=='MyEnum')].attrs" '["#[non_exhaustive]\n"]'
 #[non_exhaustive]
 pub enum MyEnum {
     First,
 }
 
 pub enum NonExhaustiveVariant {
-    //@ is "$.index[?(@.name=='Variant')].attrs" '["#[non_exhaustive]"]'
+    //@ is "$.index[?(@.name=='Variant')].attrs" '["#[non_exhaustive]\n"]'
     #[non_exhaustive]
     Variant(i64),
 }
 
-//@ is "$.index[?(@.name=='MyStruct')].attrs" '["#[non_exhaustive]"]'
+//@ is "$.index[?(@.name=='MyStruct')].attrs" '["#[non_exhaustive]\n"]'
 #[non_exhaustive]
 pub struct MyStruct {
     pub x: i64,
diff --git a/tests/rustdoc-json/keyword_private.rs b/tests/rustdoc-json/keyword_private.rs
index fea546c9fb605..5e9a2c1016366 100644
--- a/tests/rustdoc-json/keyword_private.rs
+++ b/tests/rustdoc-json/keyword_private.rs
@@ -5,7 +5,7 @@
 
 //@ !has "$.index[?(@.name=='match')]"
 //@ has  "$.index[?(@.name=='foo')]"
-//@ is   "$.index[?(@.name=='foo')].attrs" '["#[doc(keyword = \"match\")]"]'
+//@ is   "$.index[?(@.name=='foo')].attrs" '["#[doc(keyword = \"match\")]\n"]'
 //@ is   "$.index[?(@.name=='foo')].docs" '"this is a test!"'
 #[doc(keyword = "match")]
 /// this is a test!
@@ -13,7 +13,7 @@ pub mod foo {}
 
 //@ !has "$.index[?(@.name=='break')]"
 //@ has "$.index[?(@.name=='bar')]"
-//@ is   "$.index[?(@.name=='bar')].attrs" '["#[doc(keyword = \"break\")]"]'
+//@ is   "$.index[?(@.name=='bar')].attrs" '["#[doc(keyword = \"break\")]\n"]'
 //@ is   "$.index[?(@.name=='bar')].docs" '"hello"'
 #[doc(keyword = "break")]
 /// hello
diff --git a/tests/ui-fulldeps/stable-mir/check_attribute.rs b/tests/ui-fulldeps/stable-mir/check_attribute.rs
index 81d5399d88aa6..e4cc7b104b60e 100644
--- a/tests/ui-fulldeps/stable-mir/check_attribute.rs
+++ b/tests/ui-fulldeps/stable-mir/check_attribute.rs
@@ -35,12 +35,12 @@ fn test_stable_mir() -> ControlFlow<()> {
 fn test_tool(items: &CrateItems) {
     let rustfmt_fn = *get_item(&items, "do_not_format").unwrap();
     let rustfmt_attrs = rustfmt_fn.tool_attrs(&["rustfmt".to_string(), "skip".to_string()]);
-    assert_eq!(rustfmt_attrs[0].as_str(), "#[rustfmt::skip]");
+    assert_eq!(rustfmt_attrs[0].as_str(), "#[rustfmt::skip]\n");
 
     let clippy_fn = *get_item(&items, "complex_fn").unwrap();
     let clippy_attrs = clippy_fn.tool_attrs(&["clippy".to_string(),
                                                "cyclomatic_complexity".to_string()]);
-    assert_eq!(clippy_attrs[0].as_str(), "#[clippy::cyclomatic_complexity = \"100\"]");
+    assert_eq!(clippy_attrs[0].as_str(), "#[clippy::cyclomatic_complexity = \"100\"]\n");
 }
 
 fn get_item<'a>(
diff --git a/tests/ui/unpretty/exhaustive.hir.stdout b/tests/ui/unpretty/exhaustive.hir.stdout
index d2c379d436624..885135e590d2e 100644
--- a/tests/ui/unpretty/exhaustive.hir.stdout
+++ b/tests/ui/unpretty/exhaustive.hir.stdout
@@ -8,7 +8,28 @@
 // Note: the HIR revision includes a `.stderr` file because there are some
 // errors that only occur once we get past the AST.
 
-#![feature(auto_traits)]#![feature(box_patterns)]#![feature(builtin_syntax)]#![feature(concat_idents)]#![feature(const_trait_impl)]#![feature(decl_macro)]#![feature(deref_patterns)]#![feature(dyn_star)]#![feature(explicit_tail_calls)]#![feature(gen_blocks)]#![feature(more_qualified_paths)]#![feature(never_patterns)]#![feature(never_type)]#![feature(pattern_types)]#![feature(pattern_type_macro)]#![feature(prelude_import)]#![feature(specialization)]#![feature(trace_macros)]#![feature(trait_alias)]#![feature(try_blocks)]#![feature(yeet_expr)]#![allow(incomplete_features)]
+#![feature(auto_traits)]
+#![feature(box_patterns)]
+#![feature(builtin_syntax)]
+#![feature(concat_idents)]
+#![feature(const_trait_impl)]
+#![feature(decl_macro)]
+#![feature(deref_patterns)]
+#![feature(dyn_star)]
+#![feature(explicit_tail_calls)]
+#![feature(gen_blocks)]
+#![feature(more_qualified_paths)]
+#![feature(never_patterns)]
+#![feature(never_type)]
+#![feature(pattern_types)]
+#![feature(pattern_type_macro)]
+#![feature(prelude_import)]
+#![feature(specialization)]
+#![feature(trace_macros)]
+#![feature(trait_alias)]
+#![feature(try_blocks)]
+#![feature(yeet_expr)]
+#![allow(incomplete_features)]
 #[prelude_import]
 use std::prelude::rust_2024::*;
 #[macro_use]
@@ -33,20 +54,25 @@ mod prelude {
 /*!
      * inner multi-line doc comment
      */
-#[doc = "inner doc attribute"]#[allow(dead_code, unused_variables)]#[no_std]
+#[doc = "inner doc attribute"]
+#[allow(dead_code, unused_variables)]
+#[no_std]
 mod attributes {//! inner single-line doc comment
     /*!
      * inner multi-line doc comment
      */
-    #![doc =
-    "inner doc attribute"]#![allow(dead_code, unused_variables)]#![no_std]
+    #![doc = "inner doc attribute"]
+    #![allow(dead_code, unused_variables)]
+    #![no_std]
 
     /// outer single-line doc comment
     /**
      * outer multi-line doc comment
      */
-    #[doc =
-    "outer doc attribute"]#[doc = "macro"]#[allow()]#[attr = Repr([ReprC])]
+    #[doc = "outer doc attribute"]
+    #[doc = "macro"]
+    #[allow()]
+    #[attr = Repr([ReprC])]
     struct Struct;
 }
 

From 809e5b5ed17f6cede5945939bb7f10c5282d9b53 Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <n.nethercote@gmail.com>
Date: Wed, 30 Apr 2025 16:05:47 +1000
Subject: [PATCH 6/7] Fix some hir pretty-printing over-indenting.

---
 compiler/rustc_hir_pretty/src/lib.rs    | 10 ++--
 tests/ui/unpretty/exhaustive.hir.stdout | 61 ++++++++++++-------------
 2 files changed, 36 insertions(+), 35 deletions(-)

diff --git a/compiler/rustc_hir_pretty/src/lib.rs b/compiler/rustc_hir_pretty/src/lib.rs
index 1e260b2dda456..0916885cb170d 100644
--- a/compiler/rustc_hir_pretty/src/lib.rs
+++ b/compiler/rustc_hir_pretty/src/lib.rs
@@ -1503,7 +1503,7 @@ impl<'a> State<'a> {
             }
             hir::ExprKind::DropTemps(init) => {
                 // Print `{`:
-                let cb = self.cbox(INDENT_UNIT);
+                let cb = self.cbox(0);
                 let ib = self.ibox(0);
                 self.bopen(ib);
 
@@ -1530,12 +1530,14 @@ impl<'a> State<'a> {
                     self.print_ident(label.ident);
                     self.word_space(":");
                 }
-                let (cb, ib) = self.head("loop");
+                let cb = self.cbox(0);
+                let ib = self.ibox(0);
+                self.word_nbsp("loop");
                 self.print_block(blk, cb, ib);
             }
             hir::ExprKind::Match(expr, arms, _) => {
-                let cb = self.cbox(INDENT_UNIT);
-                let ib = self.ibox(INDENT_UNIT);
+                let cb = self.cbox(0);
+                let ib = self.ibox(0);
                 self.word_nbsp("match");
                 self.print_expr_as_cond(expr);
                 self.space();
diff --git a/tests/ui/unpretty/exhaustive.hir.stdout b/tests/ui/unpretty/exhaustive.hir.stdout
index 885135e590d2e..c1230e597ced8 100644
--- a/tests/ui/unpretty/exhaustive.hir.stdout
+++ b/tests/ui/unpretty/exhaustive.hir.stdout
@@ -173,32 +173,32 @@ mod expressions {
     fn expr_for_loop() {
         let x;
         {
-                let _t =
-                    match #[lang = "into_iter"](x) {
-                            mut iter =>
-                                loop {
-                                        match #[lang = "next"](&mut iter) {
-                                                #[lang = "None"] {} => break,
-                                                #[lang = "Some"] {  0: _ } => { }
-                                            }
-                                    },
-                        };
-                _t
-            };
+            let _t =
+                match #[lang = "into_iter"](x) {
+                    mut iter =>
+                        loop {
+                            match #[lang = "next"](&mut iter) {
+                                #[lang = "None"] {} => break,
+                                #[lang = "Some"] {  0: _ } => { }
+                            }
+                        },
+                };
+            _t
+        };
         {
-                let _t =
-                    match #[lang = "into_iter"](x) {
-                            mut iter =>
-                                'a:
-                                    loop {
-                                        match #[lang = "next"](&mut iter) {
-                                                #[lang = "None"] {} => break,
-                                                #[lang = "Some"] {  0: _ } => { }
-                                            }
-                                    },
-                        };
-                _t
-            }
+            let _t =
+                match #[lang = "into_iter"](x) {
+                    mut iter =>
+                        'a:
+                            loop {
+                            match #[lang = "next"](&mut iter) {
+                                #[lang = "None"] {} => break,
+                                #[lang = "Some"] {  0: _ } => { }
+                            }
+                        },
+                };
+            _t
+        }
     }
 
     /// ExprKind::Loop
@@ -383,12 +383,11 @@ mod expressions {
     fn expr_try() {
         let expr;
         match #[lang = "branch"](expr) {
-                #[lang = "Break"] {  0: residual } =>
-                    #[allow(unreachable_code)]
-                    return #[lang = "from_residual"](residual),
-                #[lang = "Continue"] {  0: val } => #[allow(unreachable_code)]
-                    val,
-            };
+            #[lang = "Break"] {  0: residual } => #[allow(unreachable_code)]
+                return #[lang = "from_residual"](residual),
+            #[lang = "Continue"] {  0: val } => #[allow(unreachable_code)]
+                val,
+        };
     }
     /// ExprKind::Yield
     fn expr_yield() { yield (); yield true; }

From 9af08429f13059fee07a6cb4b019e2bcda3a8093 Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <n.nethercote@gmail.com>
Date: Wed, 30 Apr 2025 16:23:29 +1000
Subject: [PATCH 7/7] Avoid an indent for labelled loops.

---
 compiler/rustc_ast_pretty/src/pprust/state/expr.rs | 4 ++--
 compiler/rustc_hir_pretty/src/lib.rs               | 4 ++--
 tests/ui/unpretty/exhaustive.hir.stdout            | 3 +--
 3 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/compiler/rustc_ast_pretty/src/pprust/state/expr.rs b/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
index abcbb88aab2d9..c9a7e2aebd01b 100644
--- a/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
+++ b/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
@@ -485,12 +485,12 @@ impl<'a> State<'a> {
                 self.print_block_with_attrs(body, attrs, cb, ib);
             }
             ast::ExprKind::Loop(blk, opt_label, _) => {
+                let cb = self.cbox(0);
+                let ib = self.ibox(0);
                 if let Some(label) = opt_label {
                     self.print_ident(label.ident);
                     self.word_space(":");
                 }
-                let cb = self.cbox(0);
-                let ib = self.ibox(0);
                 self.word_nbsp("loop");
                 self.print_block_with_attrs(blk, attrs, cb, ib);
             }
diff --git a/compiler/rustc_hir_pretty/src/lib.rs b/compiler/rustc_hir_pretty/src/lib.rs
index 0916885cb170d..09bf84ab64fbe 100644
--- a/compiler/rustc_hir_pretty/src/lib.rs
+++ b/compiler/rustc_hir_pretty/src/lib.rs
@@ -1526,12 +1526,12 @@ impl<'a> State<'a> {
                 self.print_if(test, blk, elseopt);
             }
             hir::ExprKind::Loop(blk, opt_label, _, _) => {
+                let cb = self.cbox(0);
+                let ib = self.ibox(0);
                 if let Some(label) = opt_label {
                     self.print_ident(label.ident);
                     self.word_space(":");
                 }
-                let cb = self.cbox(0);
-                let ib = self.ibox(0);
                 self.word_nbsp("loop");
                 self.print_block(blk, cb, ib);
             }
diff --git a/tests/ui/unpretty/exhaustive.hir.stdout b/tests/ui/unpretty/exhaustive.hir.stdout
index c1230e597ced8..c20f123b16e83 100644
--- a/tests/ui/unpretty/exhaustive.hir.stdout
+++ b/tests/ui/unpretty/exhaustive.hir.stdout
@@ -189,8 +189,7 @@ mod expressions {
             let _t =
                 match #[lang = "into_iter"](x) {
                     mut iter =>
-                        'a:
-                            loop {
+                        'a: loop {
                             match #[lang = "next"](&mut iter) {
                                 #[lang = "None"] {} => break,
                                 #[lang = "Some"] {  0: _ } => { }