bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/ide-completion/src/completions/format_string.rs')
-rw-r--r--crates/ide-completion/src/completions/format_string.rs128
1 files changed, 128 insertions, 0 deletions
diff --git a/crates/ide-completion/src/completions/format_string.rs b/crates/ide-completion/src/completions/format_string.rs
new file mode 100644
index 0000000000..f0c994f6b6
--- /dev/null
+++ b/crates/ide-completion/src/completions/format_string.rs
@@ -0,0 +1,128 @@
+//! Completes identifiers in format string literals.
+
+use ide_db::syntax_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())
+ .zip(ast::String::cast(ctx.original_token.clone()))
+ {
+ Some((expanded, original)) if is_format_string(&expanded) => original,
+ _ => return,
+ };
+ let cursor = ctx.position.offset;
+ let lit_start = ctx.original_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 works_when_wrapped() {
+ check(
+ r#"
+macro_rules! format_args {
+ ($lit:literal $(tt:tt)*) => { 0 },
+}
+macro_rules! print {
+ ($($arg:tt)*) => (std::io::_print(format_args!($($arg)*)));
+}
+fn main() {
+ let foobar = 1;
+ print!("f$0");
+}
+"#,
+ expect![[]],
+ );
+ }
+
+ #[test]
+ fn no_completion_without_brace() {
+ check(
+ r#"
+macro_rules! format_args {
+ ($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");
+}
+"#,
+ );
+ }
+}