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oak_dhall/builder/
mod.rs

1use crate::parser::DHallParser;
2#[doc = include_str!("../readme.md")]
3use crate::{ast::*, language::DHallLanguage};
4use oak_core::{Builder, BuilderCache, GreenNode, OakDiagnostics, OakError, Parser, RedNode, SourceText, TextEdit, builder::BuildOutput, source::Source};
5
6/// DHall AST builder.
7#[derive(Clone)]
8pub struct DHallBuilder<'config> {
9    config: &'config DHallLanguage,
10}
11
12impl<'config> DHallBuilder<'config> {
13    /// Creates a new `DHallBuilder`.
14    pub fn new(config: &'config DHallLanguage) -> Self {
15        Self { config }
16    }
17}
18
19impl<'config> Builder<DHallLanguage> for DHallBuilder<'config> {
20    fn build<'a, S: Source + ?Sized>(&self, source: &S, edits: &[TextEdit], _cache: &'a mut impl BuilderCache<DHallLanguage>) -> BuildOutput<DHallLanguage> {
21        let parser = DHallParser::new(self.config);
22        let mut cache = oak_core::parser::session::ParseSession::<DHallLanguage>::default();
23        let parse_result = parser.parse(source, edits, &mut cache);
24
25        match parse_result.result {
26            Ok(green_tree) => {
27                let source_text = SourceText::new(source.get_text_in((0..source.length()).into()).into_owned());
28                match self.build_root(green_tree.clone(), &source_text) {
29                    Ok(ast_root) => OakDiagnostics { result: Ok(ast_root), diagnostics: parse_result.diagnostics },
30                    Err(build_error) => {
31                        let mut diagnostics = parse_result.diagnostics;
32                        diagnostics.push(build_error.clone());
33                        OakDiagnostics { result: Err(build_error), diagnostics }
34                    }
35                }
36            }
37            Err(parse_error) => OakDiagnostics { result: Err(parse_error), diagnostics: parse_result.diagnostics },
38        }
39    }
40}
41
42impl<'config> DHallBuilder<'config> {
43    pub(crate) fn build_root(&self, green_tree: GreenNode<DHallLanguage>, source: &SourceText) -> Result<DHallRoot, OakError> {
44        let mut expressions = Vec::new();
45        let mut current_offset = 0;
46
47        for child in green_tree.children {
48            match child {
49                oak_core::GreenTree::Node(n) => {
50                    expressions.push(self.build_expr(n, current_offset, source)?);
51                    current_offset += n.byte_length as usize;
52                }
53                oak_core::GreenTree::Leaf(l) => {
54                    current_offset += l.length as usize;
55                }
56            }
57        }
58
59        Ok(DHallRoot { expressions })
60    }
61
62    fn build_expr(&self, node: &GreenNode<DHallLanguage>, offset: usize, source: &SourceText) -> Result<DHallExpr, OakError> {
63        let span = core::range::Range { start: offset, end: offset + node.byte_length as usize };
64
65        match node.kind {
66            crate::parser::element_type::DHallElementType::Identifier => {
67                let name = source.get_text_in(span.clone()).to_string();
68                Ok(DHallExpr::Identifier { name, span })
69            }
70            crate::parser::element_type::DHallElementType::Number | crate::parser::element_type::DHallElementType::String | crate::parser::element_type::DHallElementType::True | crate::parser::element_type::DHallElementType::False => {
71                let value = source.get_text_in(span.clone()).to_string();
72                Ok(DHallExpr::Literal { value, span })
73            }
74            _ => {
75                // For other types, try to find a child node that is an expression
76                for child in node.children {
77                    if let oak_core::GreenTree::Node(n) = child {
78                        return self.build_expr(n, offset, source);
79                    }
80                }
81                // Fallback
82                let name = source.get_text_in(span.clone()).to_string();
83                Ok(DHallExpr::Identifier { name, span })
84            }
85        }
86    }
87}