rust/tests/pretty
Nicholas Nethercote 925f7fad57 Improve print_tts by changing tokenstream::Spacing.
`tokenstream::Spacing` appears on all `TokenTree::Token` instances,
both punct and non-punct. Its current usage:
- `Joint` means "can join with the next token *and* that token is a
  punct".
- `Alone` means "cannot join with the next token *or* can join with the
  next token but that token is not a punct".

The fact that `Alone` is used for two different cases is awkward.
This commit augments `tokenstream::Spacing` with a new variant
`JointHidden`, resulting in:
- `Joint` means "can join with the next token *and* that token is a
  punct".
- `JointHidden` means "can join with the next token *and* that token is a
  not a punct".
- `Alone` means "cannot join with the next token".

This *drastically* improves the output of `print_tts`. For example,
this:
```
stringify!(let a: Vec<u32> = vec![];)
```
currently produces this string:
```
let a : Vec < u32 > = vec! [] ;
```
With this PR, it now produces this string:
```
let a: Vec<u32> = vec![] ;
```
(The space after the `]` is because `TokenTree::Delimited` currently
doesn't have spacing information. The subsequent commit fixes this.)

The new `print_tts` doesn't replicate original code perfectly. E.g.
multiple space characters will be condensed into a single space
character. But it's much improved.

`print_tts` still produces the old, uglier output for code produced by
proc macros. Because we have to translate the generated code from
`proc_macro::Spacing` to the more expressive `token::Spacing`, which
results in too much `proc_macro::Along` usage and no
`proc_macro::JointHidden` usage. So `space_between` still exists and
is used by `print_tts` in conjunction with the `Spacing` field.

This change will also help with the removal of `Token::Interpolated`.
Currently interpolated tokens are pretty-printed nicely via AST pretty
printing. `Token::Interpolated` removal will mean they get printed with
`print_tts`. Without this change, that would result in much uglier
output for code produced by decl macro expansions. With this change, AST
pretty printing and `print_tts` produce similar results.

The commit also tweaks the comments on `proc_macro::Spacing`. In
particular, it refers to "compound tokens" rather than "multi-char
operators" because lifetimes aren't operators.
2023-12-11 09:19:09 +11:00
..
auxiliary
asm.pp
asm.rs
ast-stmt-expr-attr.rs Remove uses of box_syntax in rustc and tools 2023-03-12 13:19:46 +00:00
async.rs
attr-derive.rs
attr-fn-inner.rs
attr-literals.rs
attr-tokens-raw-ident.rs
auto-trait.rs
blank-lines.rs
block-comment-multiple-asterisks.rs
block-comment-trailing-whitespace.rs
block-comment-trailing-whitespace2.rs
block-comment-wchar.pp
block-comment-wchar.rs
block-disambig.rs
cast-lt.pp Improve print_tts by changing tokenstream::Spacing. 2023-12-11 09:19:09 +11:00
cast-lt.rs
closure-reform-pretty.rs
delimited-token-groups.rs
disamb-stmt-expr.rs
do1.rs
doc-comments.rs
dollar-crate.pp Bless pretty tests. 2023-01-12 00:25:46 +01:00
dollar-crate.rs
empty-impl.rs
empty-lines.rs
enum-variant-vis.rs
example1.rs
example2.pp
example2.rs
expanded-and-path-remap-80832.pp
expanded-and-path-remap-80832.rs
fn-return.rs
fn-types.rs
fn-variadic.rs
for-comment.rs
format-args-str-escape.pp Preserve unicode escapes in format string literals when pretty-printing AST 2023-10-16 21:20:21 +02:00
format-args-str-escape.rs Preserve unicode escapes in format string literals when pretty-printing AST 2023-10-16 21:20:21 +02:00
gat-bounds.rs
hir-fn-variadic.pp Remove unnecessary CVarArgs name skipping logic 2023-10-25 17:44:17 +02:00
hir-fn-variadic.rs Print variadic argument pattern in HIR pretty printer 2023-10-25 17:36:04 +02:00
hir-pretty-loop.pp
hir-pretty-loop.rs
if-attr.rs
import-renames.rs
issue-4264.pp Bless pretty tests. 2023-03-16 11:21:50 +01:00
issue-4264.rs
issue-12590-a.rs
issue-12590-b.rs
issue-12590-c.pp
issue-12590-c.rs
issue-19077.rs
issue-25031.rs
issue-30731.rs
issue-31073.pp
issue-31073.rs
issue-68710-field-attr-proc-mac-lost.rs
issue-73626.rs
issue-74745.rs
issue-85089.pp
issue-85089.rs
let.rs
lifetime.rs
macro.rs
macro_rules.rs
match-block-expr.rs
match-naked-expr-medium.rs
match-naked-expr.rs
nested-item-vis-defaultness.rs
offset_of.rs Close parentheses for offset_of in AST pretty printing 2023-04-30 23:29:40 +02:00
path-type-bounds.rs
qpath-associated-type-bound.rs
raw-address-of.rs
raw-str-nonexpr.rs
stmt_expr_attributes.rs Remove uses of box_syntax in rustc and tools 2023-03-12 13:19:46 +00:00
struct-pattern.rs
struct-tuple.rs
tag-blank-lines.rs
tests-are-sorted.pp Rework no_coverage to coverage(off) 2023-09-08 12:46:06 +01:00
tests-are-sorted.rs Implementing "<test_binary> --list --format json" #107307 #49359 2023-03-15 14:20:20 -04:00
top-level-doc-comments.rs
trait-inner-attr.rs
trait-polarity.rs
trait-safety.rs
unary-op-disambig.rs
use-tree.rs
vec-comments.pp
vec-comments.rs
where-clauses.rs
yeet-expr.rs