bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

Auto merge of #106745 - m-ou-se:format-args-ast, r=oli-obk

Browse source 
Move format_args!() into AST (and expand it during AST lowering)

Implements https://github.com/rust-lang/compiler-team/issues/541

This moves FormatArgs from rustc_builtin_macros to rustc_ast_lowering. For now, the end result is the same. But this allows for future changes to do smarter things with format_args!(). It also allows Clippy to directly access the ast::FormatArgs, making things a lot easier.

This change turns the format args types into lang items. The builtin macro used to refer to them by their path. After this change, the path is no longer relevant, making it easier to make changes in `core`.

This updates clippy to use the new language items, but this doesn't yet make clippy use the ast::FormatArgs structure that's now available. That should be done after this is merged.
This commit is contained in:
bors 2023-01-26 12:44:47 +00:00
commit 3e97763872
32 changed files with 750 additions and 449 deletions
Download patch file Download diff file Expand all files Collapse all files

22
compiler/rustc_builtin_macros/src/format.rs
View file

@ -1,7 +1,11 @@
use rustc_ast::ptr::P;
use rustc_ast::token;
use rustc_ast::tokenstream::TokenStream;
use rustc_ast::Expr;
use rustc_ast::{
Expr, ExprKind, FormatAlignment, FormatArgPosition, FormatArgPositionKind, FormatArgs,
FormatArgsPiece, FormatArgument, FormatArgumentKind, FormatArguments, FormatCount,
FormatOptions, FormatPlaceholder, FormatTrait,
};
use rustc_data_structures::fx::FxHashSet;
use rustc_errors::{pluralize, Applicability, MultiSpan, PResult};
use rustc_expand::base::{self, *};
@ -12,21 +16,15 @@ use rustc_span::{BytePos, InnerSpan, Span};
use rustc_lint_defs::builtin::NAMED_ARGUMENTS_USED_POSITIONALLY;
use rustc_lint_defs::{BufferedEarlyLint, BuiltinLintDiagnostics, LintId};
mod ast;
use ast::*;
mod expand;
use expand::expand_parsed_format_args;
// The format_args!() macro is expanded in three steps:
// 1. First, `parse_args` will parse the `(literal, arg, arg, name=arg, name=arg)` syntax,
// but doesn't parse the template (the literal) itself.
// 2. Second, `make_format_args` will parse the template, the format options, resolve argument references,
// produce diagnostics, and turn the whole thing into a `FormatArgs` structure.
// 3. Finally, `expand_parsed_format_args` will turn that `FormatArgs` structure
// into the expression that the macro expands to.
// produce diagnostics, and turn the whole thing into a `FormatArgs` AST node.
// 3. Much later, in AST lowering (rustc_ast_lowering), that `FormatArgs` structure will be turned
// into the expression of type `core::fmt::Arguments`.
// See format/ast.rs for the FormatArgs structure and glossary.
// See rustc_ast/src/format.rs for the FormatArgs structure and glossary.
// Only used in parse_args and report_invalid_references,
// to indicate how a referred argument was used.
@ -850,7 +848,7 @@ fn expand_format_args_impl<'cx>(
match parse_args(ecx, sp, tts) {
Ok((efmt, args)) => {
if let Ok(format_args) = make_format_args(ecx, efmt, args, nl) {
MacEager::expr(expand_parsed_format_args(ecx, format_args))
MacEager::expr(ecx.expr(sp, ExprKind::FormatArgs(P(format_args))))
} else {
MacEager::expr(DummyResult::raw_expr(sp, true))
}