Introduce red-green syntax tree

1 files changed, 48 insertions, 4 deletions

diff --git a/src/lib.rs b/src/lib.rs
index b90b70c05..cf2e97024 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -12,7 +12,8 @@
 //!   [RFC.md]: <https://github.com/matklad/libsyntax2/blob/master/docs/RFC.md>
 
 #![forbid(missing_debug_implementations, unconditional_recursion, future_incompatible)]
-#![deny(bad_style, unsafe_code, missing_docs)]
+#![deny(bad_style, missing_docs)]
+#![allow(missing_docs)]
 //#![warn(unreachable_pub)] // rust-lang/rust#47816
 
 extern crate unicode_xid;
@@ -21,19 +22,24 @@ extern crate text_unit;
 mod tree;
 mod lexer;
 mod parser;
+mod yellow;
 
 pub mod syntax_kinds;
 pub use text_unit::{TextRange, TextUnit};
 pub use tree::{File, Node, SyntaxKind, Token};
-pub(crate) use tree::{ErrorMsg, FileBuilder, Sink};
+pub(crate) use tree::{ErrorMsg, FileBuilder, Sink, GreenBuilder};
 pub use lexer::{next_token, tokenize};
-pub use parser::parse;
+pub use yellow::SyntaxNode;
+pub(crate) use yellow::SError;
+pub use parser::{parse, parse_green};
 
 /// Utilities for simple uses of the parser.
 pub mod utils {
     use std::fmt::Write;
 
-    use {File, Node};
+    use {File, Node, SyntaxNode};
+    use std::collections::BTreeSet;
+    use SError;
 
     /// Parse a file and create a string representation of the resulting parse tree.
     pub fn dump_tree(file: &File) -> String {
@@ -65,4 +71,42 @@ pub mod utils {
             }
         }
     }
+
+    /// Parse a file and create a string representation of the resulting parse tree.
+    pub fn dump_tree_green(syntax: &SyntaxNode) -> String {
+        let mut errors: BTreeSet<_> = syntax.root.errors.iter().cloned().collect();
+        let mut result = String::new();
+        go(syntax, &mut result, 0, &mut errors);
+        return result;
+
+        fn go(node: &SyntaxNode, buff: &mut String, level: usize, errors: &mut BTreeSet<SError>) {
+            buff.push_str(&String::from("  ").repeat(level));
+            write!(buff, "{:?}\n", node).unwrap();
+//            let my_errors = node.errors().filter(|e| e.after_child().is_none());
+//            let parent_errors = node.parent()
+//                .into_iter()
+//                .flat_map(|n| n.errors())
+//                .filter(|e| e.after_child() == Some(node));
+//
+            let my_errors: Vec<_> = errors.iter().filter(|e| e.offset == node.range().start())
+                .cloned().collect();
+            for err in my_errors {
+                errors.remove(&err);
+                buff.push_str(&String::from("  ").repeat(level));
+                write!(buff, "err: `{}`\n", err.message).unwrap();
+            }
+
+            for child in node.children().iter() {
+                go(child, buff, level + 1, errors)
+            }
+
+            let my_errors: Vec<_> = errors.iter().filter(|e| e.offset == node.range().end())
+                .cloned().collect();
+            for err in my_errors {
+                errors.remove(&err);
+                buff.push_str(&String::from("  ").repeat(level));
+                write!(buff, "err: `{}`\n", err.message).unwrap();
+            }
+        }
+    }
 }