Merge #1112

1112: Fix literal support in token tree to ast item list r=matklad a=edwin0cheng

This PR implements following things :

1. Expose `next_token` from `ra_parse`
2. Fix the literal conversion in `token_tree_to_ast_item_list`
3. Add test for the conversion

Co-authored-by: Edwin Cheng <[email protected]>

3 files changed, 11 insertions, 2 deletions

diff --git a/crates/ra_syntax/src/lib.rs b/crates/ra_syntax/src/lib.rs
index e1088e296..c56bc9f16 100644
--- a/crates/ra_syntax/src/lib.rs
+++ b/crates/ra_syntax/src/lib.rs
@@ -40,7 +40,7 @@ pub use crate::{
     syntax_text::SyntaxText,
     syntax_node::{Direction,  SyntaxNode, WalkEvent, TreeArc, SyntaxTreeBuilder, SyntaxElement, SyntaxToken},
     ptr::{SyntaxNodePtr, AstPtr},
-    parsing::{tokenize, Token},
+    parsing::{tokenize, classify_literal, Token},
 };
 
 use ra_text_edit::AtomTextEdit;
diff --git a/crates/ra_syntax/src/parsing.rs b/crates/ra_syntax/src/parsing.rs
index ad5668a65..15d69c5ab 100644
--- a/crates/ra_syntax/src/parsing.rs
+++ b/crates/ra_syntax/src/parsing.rs
@@ -11,7 +11,7 @@ use crate::{
     syntax_node::GreenNode,
 };
 
-pub use self::lexer::{tokenize, Token};
+pub use self::lexer::{tokenize, classify_literal, Token};
 
 pub(crate) use self::reparsing::incremental_reparse;
 
diff --git a/crates/ra_syntax/src/parsing/lexer.rs b/crates/ra_syntax/src/parsing/lexer.rs
index 36e841609..3ae42912c 100644
--- a/crates/ra_syntax/src/parsing/lexer.rs
+++ b/crates/ra_syntax/src/parsing/lexer.rs
@@ -214,3 +214,12 @@ fn scan_literal_suffix(ptr: &mut Ptr) {
     }
     ptr.bump_while(is_ident_continue);
 }
+
+pub fn classify_literal(text: &str) -> Option<Token> {
+    let tkn = next_token(text);
+    if !tkn.kind.is_literal() || tkn.len.to_usize() != text.len() {
+        return None;
+    }
+
+    Some(tkn)
+}