Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/ide_ssr/src/fragments.rs')
| -rw-r--r-- | crates/ide_ssr/src/fragments.rs | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/crates/ide_ssr/src/fragments.rs b/crates/ide_ssr/src/fragments.rs new file mode 100644 index 0000000000..0abf9e4d98 --- /dev/null +++ b/crates/ide_ssr/src/fragments.rs @@ -0,0 +1,21 @@ +//! When specifying SSR rule, you generally want to map one *kind* of thing to +//! the same kind of thing: path to path, expression to expression, type to +//! type. +//! +//! The problem is, while this *kind* is generally obvious to the human, the ide +//! needs to determine it somehow. We do this in a stupid way -- by pasting SSR +//! rule into different contexts and checking what works. + +use parser::SyntaxKind; +use syntax::{ast, AstNode, SyntaxNode}; + +pub(crate) fn ty(s: &str) -> Result<SyntaxNode, ()> { + let template = "type T = {};"; + let input = template.replace("{}", s); + let parse = syntax::SourceFile::parse(&input); + if !parse.errors().is_empty() { + return Err(()); + } + let node = parse.tree().syntax().descendants().find_map(ast::Type::cast).ok_or(())?; + Ok(node.syntax().clone()) +} |