Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Generalize attribute syntax #93

Merged
merged 7 commits into from
Mar 9, 2022
Merged

Generalize attribute syntax #93

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
7 commits
Select commit Hold shift + click to select a range
1411c8b
Add tests for attributes not in meta-item form
ninevra Nov 14, 2020
a609d14
Handle non-built-in attrs as attr-items
ninevra Nov 14, 2020
63dfc35
Revise tests to expect attr_item for custom attrs
ninevra Nov 14, 2020
2448511
Cite source for derive macro helper example
ninevra Mar 8, 2022
2c4c443
Test expressions in key-value attributes
ninevra Mar 8, 2022
ecbce1e
Accept name = expr in attributes
ninevra Mar 8, 2022
467fd2c
Alias delim_token_tree to token_tree
ninevra Mar 8, 2022
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
141 changes: 133 additions & 8 deletions corpus/declarations.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -176,13 +176,13 @@ fn accumulate(self) -> Machine<{State::Accumulate}> {}
name: (identifier)
parameters: (parameters
(attribute_item
(meta_item
(attr_item
(identifier)))
(parameter
pattern: (identifier)
type: (primitive_type))
(attribute_item
(meta_item
(attr_item
(identifier)))
(parameter
pattern: (identifier)
Expand Down Expand Up @@ -473,7 +473,7 @@ struct Inches(i32);
(field_identifier)
(primitive_type))
(attribute_item
(meta_item
(attr_item
(identifier)))
(field_declaration
(field_identifier)
Expand Down Expand Up @@ -632,10 +632,10 @@ pub enum Node<T: Item> {
(field_identifier)
(primitive_type))))
(attribute_item
(meta_item
(attr_item
(identifier)))
(attribute_item
(meta_item
(attr_item
(identifier)))
(enum_variant
(identifier)
Expand Down Expand Up @@ -968,7 +968,7 @@ mod macos_only {}
path: (identifier)
name: (identifier))))))
(attribute_item
(meta_item
(attr_item
(scoped_identifier
path: (identifier)
name: (identifier))
Expand Down Expand Up @@ -996,6 +996,131 @@ mod macos_only {
(identifier)
value: (string_literal))))))))

================================================================================
Key-Value Attribute Expressions
================================================================================

#[doc = include_str!("foo-doc.md")]
fn foo() {}

#[namespace = foo::bar]
fn baz() {}

--------------------------------------------------------------------------------

(source_file
(attribute_item
(meta_item
(identifier)
(macro_invocation
(identifier)
(token_tree
(string_literal)))))
(function_item
(identifier)
(parameters)
(block))
(attribute_item
(attr_item
(identifier)
(scoped_identifier
(identifier)
(identifier))))
(function_item
(identifier)
(parameters)
(block)))

================================================================================
Attribute macros
================================================================================

foo(#[attr(=> arbitrary tokens <=)] x, y);

foo(#[bar(some tokens are special in other contexts: $/';()*()+.)] x);

--------------------------------------------------------------------------------

(source_file
(expression_statement
(call_expression
function: (identifier)
arguments: (arguments
(attribute_item (attr_item
(identifier)
arguments: (token_tree (identifier) (identifier))))
(identifier)
(identifier))))
(expression_statement
(call_expression
function: (identifier)
arguments: (arguments
(attribute_item (attr_item
(identifier)
arguments: (token_tree
(identifier)
(identifier)
(identifier)
(identifier)
(identifier)
(identifier)
(identifier)
(token_tree)
(token_tree))))
(identifier)))))

================================================================================
Derive macro helper attributes
================================================================================

// Example from https://github.com/dtolnay/thiserror/blob/21c26903e29cb92ba1a7ff11e82ae2001646b60d/README.md

use thiserror::Error;

#[derive(Error, Debug)]
pub enum Error {
#[error("first letter must be lowercase but was {:?}", first_char(.0))]
WrongCase(String),
#[error("invalid index {idx}, expected at least {} and at most {}", .limits.lo, .limits.hi)]
OutOfBounds { idx: usize, limits: Limits },
}

--------------------------------------------------------------------------------

(source_file
(line_comment)
(use_declaration
(scoped_identifier (identifier) (identifier)))
(attribute_item
(meta_item (identifier)
(meta_arguments
(meta_item (identifier))
(meta_item (identifier)))))
(enum_item
(visibility_modifier)
(type_identifier)
(enum_variant_list
(attribute_item (attr_item
(identifier)
(token_tree
(string_literal)
(identifier)
(token_tree (integer_literal)))))
(enum_variant (identifier)
(ordered_field_declaration_list (type_identifier)))
(attribute_item (attr_item
(identifier)
(token_tree
(string_literal)
(identifier)
(identifier)
(identifier)
(identifier))))
(enum_variant (identifier)
(field_declaration_list
(field_declaration (field_identifier) (primitive_type))
(field_declaration (field_identifier) (type_identifier)))))))

================================================================================
Attributes and Expressions
================================================================================
Expand Down Expand Up @@ -1032,7 +1157,7 @@ fn foo() {
pattern: (identifier)
value: (array_expression
(attribute_item
(meta_item
(attr_item
(identifier)))
(integer_literal)
(integer_literal)
Expand All @@ -1041,7 +1166,7 @@ fn foo() {
pattern: (identifier)
value: (tuple_expression
(attribute_item
(meta_item
(attr_item
(identifier)))
(integer_literal)
(integer_literal)
Expand Down
2 changes: 1 addition & 1 deletion corpus/expressions.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -607,7 +607,7 @@ let msg = match x {
value: (integer_literal))
(match_arm
(attribute_item
(meta_item
(attr_item
(identifier)))
pattern: (match_pattern
(integer_literal))
Expand Down
79 changes: 76 additions & 3 deletions grammar.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -35,6 +35,54 @@ const numeric_types = [

const primitive_types = numeric_types.concat(['bool', 'str', 'char'])

const built_in_attributes = [
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Would it be possible to add a link to a section of the rust reference manual that lists those builtin attributes?

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Sure? I'm not sure how best to do that given this PR has already been merged - should I create a second PR for that and any other changes that might be requested on review?

The reference section is https://doc.rust-lang.org/reference/attributes.html#built-in-attributes-index.

Keeping this updated is a little more complicated than checking that list; according to the current reference, only "most" built-in attributes follow the meta item syntax (although I haven't yet found one that doesn't), and additionally there may be other well-known attributes (e.g. tool attributes) that do use the meta item syntax.

Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

You can make a second PR, or maybe because it's a small thing, you can fix it when you make another PR for fixing another problem.

'cfg',
'cfg_attr',
'test',
'ignore',
'should_panic',
'derive',
'automatically_derived',
'macro_export',
'macro_use',
'proc_macro',
'proc_macro_derive',
'proc_macro_attribute',
'allow',
'warn',
'deny',
'forbid',
'deprecated',
'must_use',
'link',
'link_name',
'no_link',
'repr',
'crate_type',
'no_main',
'export_name',
'link_section',
'no_mangle',
'used',
'crate_name',
'inline',
'cold',
'no_builtins',
'target_feature',
'track_caller',
'doc',
'no_std',
'no_implicit_prelude',
'path',
'recursion_limit',
'type_length_limit',
'panic_handler',
'global_allocator',
'windows_subsystem',
'feature',
'non_exhaustive'
]

module.exports = grammar({
name: 'rust',

Expand Down Expand Up @@ -210,22 +258,47 @@ module.exports = grammar({
attribute_item: $ => seq(
'#',
'[',
$.meta_item,
$._attr,
']'
),

inner_attribute_item: $ => seq(
'#',
'!',
'[',
$.meta_item,
$._attr,
']'
),

_attr: $ => choice(
alias($.built_in_attr, $.meta_item),
alias($.custom_attr, $.attr_item),
),

custom_attr: $ => seq(
$._path,
optional(choice(
seq('=', field('value', $._expression)),
field('arguments', alias($.delim_token_tree, $.token_tree))
))
),

built_in_attr: $ => seq(
$._built_in_attr_path,
optional(choice(
seq('=', field('value', $._expression)),
field('arguments', $.meta_arguments)
))
),

_built_in_attr_path: $ => choice(
...built_in_attributes.map(name => alias(name, $.identifier))
),

meta_item: $ => seq(
$._path,
optional(choice(
seq('=', field('value', $._literal)),
seq('=', field('value', $._expression)),
field('arguments', $.meta_arguments)
))
),
Expand Down