feat: Add very simplistic ident completion for format_args! macro input

This commit is contained in:
Lukas Wirth 2022-01-15 12:12:02 +01:00
parent 2c36102722
commit 82fccb971e
8 changed files with 163 additions and 39 deletions

View file

@ -5,7 +5,10 @@
//!
//! So, this modules should not be used during hir construction, it exists
//! purely for "IDE needs".
use std::{iter::once, sync::Arc};
use std::{
iter::{self, once},
sync::Arc,
};
use hir_def::{
body::{
@ -25,7 +28,7 @@ use hir_ty::{
};
use syntax::{
ast::{self, AstNode},
SyntaxNode, TextRange, TextSize,
SyntaxKind, SyntaxNode, TextRange, TextSize,
};
use crate::{
@ -488,14 +491,20 @@ fn scope_for_offset(
.scope_by_expr()
.iter()
.filter_map(|(id, scope)| {
let source = source_map.expr_syntax(*id).ok()?;
// FIXME: correctly handle macro expansion
if source.file_id != offset.file_id {
return None;
let InFile { file_id, value } = source_map.expr_syntax(*id).ok()?;
if offset.file_id == file_id {
let root = db.parse_or_expand(file_id)?;
let node = value.to_node(&root);
return Some((node.syntax().text_range(), scope));
}
let root = source.file_syntax(db.upcast());
let node = source.value.to_node(&root);
Some((node.syntax().text_range(), scope))
// FIXME handle attribute expansion
let source = iter::successors(file_id.call_node(db.upcast()), |it| {
it.file_id.call_node(db.upcast())
})
.find(|it| it.file_id == offset.file_id)
.filter(|it| it.value.kind() == SyntaxKind::MACRO_CALL)?;
Some((source.value.text_range(), scope))
})
// find containing scope
.min_by_key(|(expr_range, _scope)| {

View file

@ -1,8 +1,8 @@
//! Syntax highlighting for format macro strings.
use ide_db::SymbolKind;
use ide_db::{helpers::format_string::is_format_string, SymbolKind};
use syntax::{
ast::{self, FormatSpecifier, HasFormatSpecifier},
AstNode, AstToken, TextRange,
TextRange,
};
use crate::{syntax_highlighting::highlights::Highlights, HlRange, HlTag};
@ -13,7 +13,7 @@ pub(super) fn highlight_format_string(
expanded_string: &ast::String,
range: TextRange,
) {
if is_format_string(expanded_string).is_none() {
if !is_format_string(expanded_string) {
return;
}
@ -28,32 +28,6 @@ pub(super) fn highlight_format_string(
});
}
fn is_format_string(string: &ast::String) -> Option<()> {
// Check if `string` is a format string argument of a macro invocation.
// `string` is a string literal, mapped down into the innermost macro expansion.
// Since `format_args!` etc. remove the format string when expanding, but place all arguments
// in the expanded output, we know that the string token is (part of) the format string if it
// appears in `format_args!` (otherwise it would have been mapped down further).
//
// This setup lets us correctly highlight the components of `concat!("{}", "bla")` format
// strings. It still fails for `concat!("{", "}")`, but that is rare.
let macro_call = string.syntax().ancestors().find_map(ast::MacroCall::cast)?;
let name = macro_call.path()?.segment()?.name_ref()?;
if !matches!(
name.text().as_str(),
"format_args" | "format_args_nl" | "const_format_args" | "panic_2015" | "panic_2021"
) {
return None;
}
// NB: we match against `panic_2015`/`panic_2021` here because they have a special-cased arm for
// `"{}"`, which otherwise wouldn't get highlighted.
Some(())
}
fn highlight_format_specifier(kind: FormatSpecifier) -> Option<HlTag> {
Some(match kind {
FormatSpecifier::Open

View file

@ -14,6 +14,7 @@ pub(crate) mod record;
pub(crate) mod snippet;
pub(crate) mod trait_impl;
pub(crate) mod unqualified_path;
pub(crate) mod format_string;
use std::iter;

View file

@ -0,0 +1,107 @@
//! Completes identifiers in format string literals.
use ide_db::helpers::format_string::is_format_string;
use itertools::Itertools;
use syntax::{ast, AstToken, TextRange, TextSize};
use crate::{context::CompletionContext, CompletionItem, CompletionItemKind, Completions};
/// Complete identifiers in format strings.
pub(crate) fn format_string(acc: &mut Completions, ctx: &CompletionContext) {
let string = match ast::String::cast(ctx.token.clone()) {
Some(it) if is_format_string(&it) => it,
_ => return,
};
let cursor = ctx.position.offset;
let lit_start = ctx.token.text_range().start();
let cursor_in_lit = cursor - lit_start;
let prefix = &string.text()[..cursor_in_lit.into()];
let braces = prefix.char_indices().rev().skip_while(|&(_, c)| c.is_alphanumeric()).next_tuple();
let brace_offset = match braces {
// escaped brace
Some(((_, '{'), (_, '{'))) => return,
Some(((idx, '{'), _)) => lit_start + TextSize::from(idx as u32 + 1),
_ => return,
};
let source_range = TextRange::new(brace_offset, cursor);
ctx.locals.iter().for_each(|(name, _)| {
CompletionItem::new(CompletionItemKind::Binding, source_range, name.to_smol_str())
.add_to(acc);
})
}
#[cfg(test)]
mod tests {
use expect_test::{expect, Expect};
use crate::tests::{check_edit, completion_list_no_kw};
fn check(ra_fixture: &str, expect: Expect) {
let actual = completion_list_no_kw(ra_fixture);
expect.assert_eq(&actual);
}
#[test]
fn no_completion_without_brace() {
check(
r#"
macro_rules! format_args {
($lit:literal $(tt:tt)*) => { 0 },
}
fn main() {
let foobar = 1;
format_args!("f$0");
}
"#,
expect![[]],
);
}
#[test]
fn completes_locals() {
check_edit(
"foobar",
r#"
macro_rules! format_args {
($lit:literal $(tt:tt)*) => { 0 },
}
fn main() {
let foobar = 1;
format_args!("{f$0");
}
"#,
r#"
macro_rules! format_args {
($lit:literal $(tt:tt)*) => { 0 },
}
fn main() {
let foobar = 1;
format_args!("{foobar");
}
"#,
);
check_edit(
"foobar",
r#"
macro_rules! format_args {
($lit:literal $(tt:tt)*) => { 0 },
}
fn main() {
let foobar = 1;
format_args!("{$0");
}
"#,
r#"
macro_rules! format_args {
($lit:literal $(tt:tt)*) => { 0 },
}
fn main() {
let foobar = 1;
format_args!("{foobar");
}
"#,
);
}
}

View file

@ -179,7 +179,7 @@ pub(crate) fn complete_postfix(acc: &mut Completions, ctx: &CompletionContext) {
}
postfix_snippet("box", "Box::new(expr)", &format!("Box::new({})", receiver_text)).add_to(acc);
postfix_snippet("dbg", "dbg!(expr)", &format!("dbg!({})", receiver_text)).add_to(acc);
postfix_snippet("dbg", "dbg!(expr)", &format!("dbg!({})", receiver_text)).add_to(acc); // fixme
postfix_snippet("dbgr", "dbg!(&expr)", &format!("dbg!(&{})", receiver_text)).add_to(acc);
postfix_snippet("call", "function(expr)", &format!("${{1}}({})", receiver_text)).add_to(acc);

View file

@ -168,6 +168,7 @@ pub fn completions(
completions::flyimport::import_on_the_fly(&mut acc, &ctx);
completions::lifetime::complete_lifetime(&mut acc, &ctx);
completions::lifetime::complete_label(&mut acc, &ctx);
completions::format_string::format_string(&mut acc, &ctx);
Some(acc)
}

View file

@ -7,6 +7,7 @@ pub mod merge_imports;
pub mod insert_whitespace_into_node;
pub mod node_ext;
pub mod rust_doc;
pub mod format_string;
use std::{collections::VecDeque, iter};

View file

@ -0,0 +1,31 @@
//! Tools to work with format string literals for the `format_args!` family of macros.
use syntax::{ast, AstNode, AstToken};
pub fn is_format_string(string: &ast::String) -> bool {
// Check if `string` is a format string argument of a macro invocation.
// `string` is a string literal, mapped down into the innermost macro expansion.
// Since `format_args!` etc. remove the format string when expanding, but place all arguments
// in the expanded output, we know that the string token is (part of) the format string if it
// appears in `format_args!` (otherwise it would have been mapped down further).
//
// This setup lets us correctly highlight the components of `concat!("{}", "bla")` format
// strings. It still fails for `concat!("{", "}")`, but that is rare.
(|| {
let macro_call = string.syntax().ancestors().find_map(ast::MacroCall::cast)?;
let name = macro_call.path()?.segment()?.name_ref()?;
if !matches!(
name.text().as_str(),
"format_args" | "format_args_nl" | "const_format_args" | "panic_2015" | "panic_2021"
) {
return None;
}
// NB: we match against `panic_2015`/`panic_2021` here because they have a special-cased arm for
// `"{}"`, which otherwise wouldn't get highlighted.
Some(())
})()
.is_some()
}