Improve hir pretty printing

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()`");
     }
 }
 

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>) {
@@ -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);
             }
@@ -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 {

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(
@@ -183,7 +184,7 @@ 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),
@@ -654,10 +655,11 @@ 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");
@@ -764,14 +766,6 @@ 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");
@@ -1509,7 +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);
 
@@ -1532,16 +1526,18 @@ 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, ib) = self.head("loop");
+                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();
@@ -1572,15 +1568,6 @@ 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 {

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]

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' '[]'

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() {}

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() {}

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> {}

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() {}

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() {}

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,

tests/rustdoc-json/keyword_private.rs

@@ -5,15 +5,15 @@
 
 //@ !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!
 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

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>(

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");
     }
+}