sigil_stitch/
code_node.rs

1//! Tree-based intermediate representation for code generation.
2//!
3//! `CodeNode` is the internal IR used by [`CodeBlock`](crate::code_block::CodeBlock).
4//! Each node is self-contained — type references, names, and nested blocks are
5//! stored inline rather than in a separate argument vector. This enables natural
6//! tree traversal for import collection, structural transformation, and rendering.
7
8use crate::code_block::{Arg, CodeBlock, FormatPart, Specifier};
9use crate::type_name::TypeName;
10
11/// A single node in the code generation tree.
12///
13/// Each variant is self-contained: a type reference is `CodeNode::TypeRef(TypeName)`,
14/// not a separate format tag plus a positional argument.
15#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
16#[non_exhaustive]
17pub enum CodeNode {
18    /// Literal text (no interpolation).
19    Literal(String),
20    /// A type reference with import tracking (was `%T` + `Arg::TypeName`).
21    TypeRef(TypeName),
22    /// A name identifier (was `%N` + `Arg::Name`).
23    NameRef(String),
24    /// A string literal value, rendered with language-specific quoting
25    /// (was `%S` + `Arg::StringLit`).
26    StringLit(String),
27    /// An inline literal string (was `%L` + `Arg::Literal`).
28    InlineLiteral(String),
29    /// A nested code block (was `%L` + `Arg::Code`).
30    Nested(CodeBlock),
31    /// A comment line. Rendered as `{prefix} {text}{suffix}` using the
32    /// language's comment syntax.
33    Comment(String),
34    /// Soft line break point (`%W`). In direct mode emits a space; in pretty
35    /// mode becomes `BoxDoc::softline()`.
36    SoftBreak,
37    /// Increase indent level (`%>`).
38    Indent,
39    /// Decrease indent level (`%<`).
40    Dedent,
41    /// Statement begin marker (`%[`). Triggers `ensure_indent()`.
42    StatementBegin,
43    /// Statement end marker (`%]`). Emits `;` if the language uses semicolons.
44    StatementEnd,
45    /// Hard newline.
46    Newline,
47    /// Block open delimiter, resolved at render time via `lang.block_syntax().block_open`.
48    BlockOpen,
49    /// Block open with an overridden delimiter string.
50    BlockOpenOverride(String),
51    /// Terminal block close delimiter, resolved via `lang.block_syntax().block_close`.
52    BlockClose,
53    /// Transitional block close delimiter (e.g. `} else`), resolved via
54    /// `lang.block_syntax().block_close` + `" "`.
55    BlockCloseTransition,
56    /// A sequence of nodes (for grouping, e.g. a statement or control flow block).
57    Sequence(Vec<CodeNode>),
58}
59
60/// Convert legacy `(FormatPart, Arg)` parallel vectors into `Vec<CodeNode>`.
61///
62/// Used by `CodeBlockBuilder::add()` which still calls `parse_format()` to get
63/// `Vec<FormatPart>`, then zips with args into self-contained nodes.
64pub(crate) fn parts_args_to_nodes(parts: &[FormatPart], args: &[Arg]) -> Vec<CodeNode> {
65    let mut nodes = Vec::with_capacity(parts.len());
66    let mut arg_index = 0;
67
68    for part in parts {
69        let node = match part {
70            FormatPart::Literal(text) => CodeNode::Literal(text.clone()),
71            FormatPart::Arg(spec) => {
72                let arg = &args[arg_index];
73                arg_index += 1;
74                match (spec, arg) {
75                    (Specifier::Type, Arg::TypeName(tn)) => CodeNode::TypeRef(tn.clone()),
76                    (Specifier::Name, Arg::Name(n)) => CodeNode::NameRef(n.clone()),
77                    (Specifier::StringLit, Arg::StringLit(s)) => CodeNode::StringLit(s.clone()),
78                    (Specifier::Literal, Arg::Literal(s)) => CodeNode::InlineLiteral(s.clone()),
79                    (Specifier::Literal, Arg::Code(block)) => CodeNode::Nested(block.clone()),
80                    _ => CodeNode::Literal(String::new()),
81                }
82            }
83            FormatPart::Wrap => CodeNode::SoftBreak,
84            FormatPart::Indent => CodeNode::Indent,
85            FormatPart::Dedent => CodeNode::Dedent,
86            FormatPart::StatementBegin => CodeNode::StatementBegin,
87            FormatPart::StatementEnd => CodeNode::StatementEnd,
88            FormatPart::Newline => CodeNode::Newline,
89            FormatPart::BlockOpen => CodeNode::BlockOpen,
90            FormatPart::BlockOpenOverride(s) => CodeNode::BlockOpenOverride(s.clone()),
91            FormatPart::BlockClose => CodeNode::BlockClose,
92            FormatPart::BlockCloseTransition => CodeNode::BlockCloseTransition,
93        };
94        nodes.push(node);
95    }
96
97    nodes
98}
99
100#[cfg(test)]
101mod tests {
102    use super::*;
103    use crate::code_block::CodeBlock;
104    use crate::type_name::TypeName;
105
106    #[test]
107    fn test_literal_conversion() {
108        let parts = vec![FormatPart::Literal("hello".to_string())];
109        let args = vec![];
110        let nodes = parts_args_to_nodes(&parts, &args);
111        assert_eq!(nodes.len(), 1);
112        assert!(matches!(&nodes[0], CodeNode::Literal(s) if s == "hello"));
113    }
114
115    #[test]
116    fn test_type_ref_conversion() {
117        let tn = TypeName::primitive("string");
118        let parts = vec![
119            FormatPart::Literal("x: ".to_string()),
120            FormatPart::Arg(Specifier::Type),
121        ];
122        let args = vec![Arg::TypeName(tn)];
123        let nodes = parts_args_to_nodes(&parts, &args);
124        assert_eq!(nodes.len(), 2);
125        assert!(matches!(&nodes[0], CodeNode::Literal(s) if s == "x: "));
126        assert!(matches!(&nodes[1], CodeNode::TypeRef(_)));
127    }
128
129    #[test]
130    fn test_nested_block_conversion() {
131        let inner = CodeBlock::of("inner()", ()).unwrap();
132        let parts = vec![FormatPart::Arg(Specifier::Literal)];
133        let args = vec![Arg::Code(inner)];
134        let nodes = parts_args_to_nodes(&parts, &args);
135        assert_eq!(nodes.len(), 1);
136        assert!(matches!(&nodes[0], CodeNode::Nested(_)));
137    }
138
139    #[test]
140    fn test_structural_nodes() {
141        let parts = vec![
142            FormatPart::Indent,
143            FormatPart::StatementBegin,
144            FormatPart::Literal("x".to_string()),
145            FormatPart::StatementEnd,
146            FormatPart::Newline,
147            FormatPart::Dedent,
148        ];
149        let nodes = parts_args_to_nodes(&parts, &[]);
150        assert_eq!(nodes.len(), 6);
151        assert!(matches!(nodes[0], CodeNode::Indent));
152        assert!(matches!(nodes[1], CodeNode::StatementBegin));
153        assert!(matches!(nodes[3], CodeNode::StatementEnd));
154        assert!(matches!(nodes[4], CodeNode::Newline));
155        assert!(matches!(nodes[5], CodeNode::Dedent));
156    }
157
158    #[test]
159    fn test_soft_break_conversion() {
160        let parts = vec![
161            FormatPart::Literal("a".to_string()),
162            FormatPart::Wrap,
163            FormatPart::Literal("b".to_string()),
164        ];
165        let nodes = parts_args_to_nodes(&parts, &[]);
166        assert_eq!(nodes.len(), 3);
167        assert!(matches!(nodes[1], CodeNode::SoftBreak));
168    }
169
170    #[test]
171    fn test_block_open_close_conversion() {
172        let parts = vec![
173            FormatPart::BlockOpen,
174            FormatPart::BlockClose,
175            FormatPart::BlockOpenOverride("where".to_string()),
176            FormatPart::BlockCloseTransition,
177        ];
178        let nodes = parts_args_to_nodes(&parts, &[]);
179        assert_eq!(nodes.len(), 4);
180        assert!(matches!(nodes[0], CodeNode::BlockOpen));
181        assert!(matches!(nodes[1], CodeNode::BlockClose));
182        assert!(matches!(&nodes[2], CodeNode::BlockOpenOverride(s) if s == "where"));
183        assert!(matches!(nodes[3], CodeNode::BlockCloseTransition));
184    }
185
186    #[test]
187    fn test_mixed_args_conversion() {
188        let tn = TypeName::primitive("number");
189        let parts = vec![
190            FormatPart::Literal("let ".to_string()),
191            FormatPart::Arg(Specifier::Name),
192            FormatPart::Literal(": ".to_string()),
193            FormatPart::Arg(Specifier::Type),
194            FormatPart::Literal(" = ".to_string()),
195            FormatPart::Arg(Specifier::StringLit),
196        ];
197        let args = vec![
198            Arg::Name("x".to_string()),
199            Arg::TypeName(tn),
200            Arg::StringLit("hello".to_string()),
201        ];
202        let nodes = parts_args_to_nodes(&parts, &args);
203        assert_eq!(nodes.len(), 6);
204        assert!(matches!(&nodes[1], CodeNode::NameRef(s) if s == "x"));
205        assert!(matches!(&nodes[3], CodeNode::TypeRef(_)));
206        assert!(matches!(&nodes[5], CodeNode::StringLit(s) if s == "hello"));
207    }
208}
sigil_stitch/code_node.rs

sigil_stitch/
code_node.rs
