weaveffi_core/
utils.rs

1/// Build the C symbol name for a function: `weaveffi_<module>_<func>`.
2pub fn c_symbol_name(module: &str, func: &str) -> String {
3    format!("weaveffi_{}_{}", module, func)
4}
5
6/// Comment syntax used to emit the standard prelude/trailer in generated files.
7#[derive(Debug, Clone, Copy, PartialEq, Eq)]
8pub enum CommentStyle {
9    /// `// ...` line comments (C, C++, Swift, Kotlin, JS/TS, C#, Dart, Go).
10    DoubleSlash,
11    /// `# ...` line comments (Python, Ruby, YAML, TOML, CMake, GYP, gradle.properties).
12    Hash,
13    /// `<!-- ... -->` block comments (XML, HTML, Markdown).
14    Xml,
15}
16
17impl CommentStyle {
18    fn open(self) -> &'static str {
19        match self {
20            Self::DoubleSlash => "// ",
21            Self::Hash => "# ",
22            Self::Xml => "<!-- ",
23        }
24    }
25
26    fn close(self) -> &'static str {
27        match self {
28            Self::Xml => " -->",
29            _ => "",
30        }
31    }
32}
33
34/// Renders the standard `Generated by WeaveFFI {VERSION} from {input}` prelude
35/// followed by the `DO NOT EDIT` warning and a regenerate command. Trailing
36/// blank line included so generators can append their content directly.
37pub fn render_prelude(style: CommentStyle, input_basename: &str) -> String {
38    let version = env!("CARGO_PKG_VERSION");
39    let o = style.open();
40    let c = style.close();
41    format!(
42        "{o}Generated by WeaveFFI {version} from {input_basename}{c}\n\
43         {o}DO NOT EDIT — your changes will be overwritten.{c}\n\
44         {o}To regenerate: weaveffi generate {input_basename} -o <out>{c}\n\n"
45    )
46}
47
48/// Renders the closing `END {filename}` marker. Caller is responsible for any
49/// preceding newline; the returned string ends with `\n`.
50pub fn render_trailer(style: CommentStyle, filename: &str) -> String {
51    let o = style.open();
52    let c = style.close();
53    format!("{o}END {filename}{c}\n")
54}
55
56/// Renders the JSON-friendly prelude as `"//"` key/value pairs (recognised by
57/// npm). Each line is two-space-indented and comma-terminated so it can be
58/// embedded at the top of any JSON object literal that opens with `{` on the
59/// previous line.
60pub fn render_json_prelude(input_basename: &str) -> String {
61    let version = env!("CARGO_PKG_VERSION");
62    format!(
63        "  \"//\": \"Generated by WeaveFFI {version} from {input_basename}\",\n  \
64         \"//warning\": \"DO NOT EDIT — your changes will be overwritten.\",\n  \
65         \"//regenerate\": \"To regenerate: weaveffi generate {input_basename} -o <out>\",\n"
66    )
67}
68
69/// Symbols (functions and types) exported by the `weaveffi-abi` runtime crate.
70///
71/// Generators that emit C/C++ headers use this list to produce
72/// `#define {prefix}_{name} weaveffi_{name}` aliases at the top of the header
73/// when a non-default `c_prefix` is configured, so consumer code can refer to
74/// runtime helpers by the prefixed name while still linking against the
75/// canonical `weaveffi_*` symbols supplied by `weaveffi-abi`.
76pub const ABI_RUNTIME_SYMBOLS: &[&str] = &[
77    "error",
78    "handle_t",
79    "error_set",
80    "error_clear",
81    "free_string",
82    "free_bytes",
83    "arena_create",
84    "arena_destroy",
85    "arena_register",
86    "cancel_token",
87    "cancel_token_create",
88    "cancel_token_cancel",
89    "cancel_token_is_cancelled",
90    "cancel_token_destroy",
91];
92
93/// Render a `#define {prefix}_{name} weaveffi_{name}` block for runtime ABI
94/// symbols. Returns an empty string when `prefix == "weaveffi"`.
95pub fn render_abi_prefix_aliases(prefix: &str) -> String {
96    if prefix == "weaveffi" {
97        return String::new();
98    }
99    let mut out = String::new();
100    out.push_str("/* Aliases for weaveffi-abi runtime symbols */\n");
101    for sym in ABI_RUNTIME_SYMBOLS {
102        out.push_str(&format!("#define {prefix}_{sym} weaveffi_{sym}\n"));
103    }
104    out.push('\n');
105    out
106}
107
108/// Build the wrapper function name exposed to the foreign language.
109///
110/// When `strip_module_prefix` is `true`, returns just `func`.
111/// When `false`, returns `{module}_{func}`.
112pub fn wrapper_name(module: &str, func: &str, strip_module_prefix: bool) -> String {
113    if strip_module_prefix {
114        func.to_string()
115    } else {
116        format!("{module}_{func}")
117    }
118}
119
120/// Extract the local type name from a potentially qualified `module.TypeName`.
121///
122/// `"other.Contact"` → `"Contact"`, `"Contact"` → `"Contact"`.
123pub fn local_type_name(name: &str) -> &str {
124    name.split_once('.').map_or(name, |(_, local)| local)
125}
126
127/// Build the C ABI struct name, resolving cross-module qualified references.
128///
129/// `"other.Contact"` with any current module → `"{prefix}_other_Contact"`.
130/// `"Contact"` with current module `"math"` → `"{prefix}_math_Contact"`.
131pub fn c_abi_struct_name(name: &str, current_module: &str, prefix: &str) -> String {
132    if let Some((mod_name, type_name)) = name.split_once('.') {
133        format!("{prefix}_{mod_name}_{type_name}")
134    } else {
135        format!("{prefix}_{current_module}_{name}")
136    }
137}
138
139#[cfg(test)]
140mod tests {
141    use super::*;
142
143    #[test]
144    fn local_type_name_unqualified() {
145        assert_eq!(local_type_name("Contact"), "Contact");
146    }
147
148    #[test]
149    fn local_type_name_qualified() {
150        assert_eq!(local_type_name("other.Contact"), "Contact");
151    }
152
153    #[test]
154    fn c_abi_struct_name_unqualified() {
155        assert_eq!(
156            c_abi_struct_name("Contact", "math", "weaveffi"),
157            "weaveffi_math_Contact"
158        );
159    }
160
161    #[test]
162    fn c_abi_struct_name_qualified() {
163        assert_eq!(
164            c_abi_struct_name("types.Name", "ops", "weaveffi"),
165            "weaveffi_types_Name"
166        );
167    }
168
169    #[test]
170    fn abi_prefix_aliases_default_is_empty() {
171        assert!(render_abi_prefix_aliases("weaveffi").is_empty());
172    }
173
174    #[test]
175    fn abi_prefix_aliases_custom_lists_every_symbol() {
176        let out = render_abi_prefix_aliases("myffi");
177        for sym in ABI_RUNTIME_SYMBOLS {
178            let line = format!("#define myffi_{sym} weaveffi_{sym}");
179            assert!(out.contains(&line), "missing alias `{line}` in:\n{out}");
180        }
181    }
182
183    #[test]
184    fn prelude_double_slash_carries_required_phrases() {
185        let p = render_prelude(CommentStyle::DoubleSlash, "calc.yml");
186        assert!(p.starts_with("// Generated by WeaveFFI "));
187        assert!(p.contains(" from calc.yml\n"));
188        assert!(p.contains("// DO NOT EDIT"));
189        assert!(p.contains("// To regenerate: weaveffi generate calc.yml -o <out>"));
190        assert!(p.ends_with("\n\n"));
191    }
192
193    #[test]
194    fn prelude_hash_uses_hash_marker() {
195        let p = render_prelude(CommentStyle::Hash, "calc.yml");
196        assert!(p.starts_with("# Generated by WeaveFFI "));
197        assert!(p.contains("# DO NOT EDIT"));
198        assert!(p.contains("# To regenerate: weaveffi generate calc.yml -o <out>"));
199    }
200
201    #[test]
202    fn prelude_xml_wraps_lines_in_brackets() {
203        let p = render_prelude(CommentStyle::Xml, "calc.yml");
204        assert!(p.starts_with("<!-- Generated by WeaveFFI "));
205        assert!(p.contains("from calc.yml -->"));
206        assert!(p.contains("<!-- DO NOT EDIT"));
207        assert!(p.contains("your changes will be overwritten. -->"));
208    }
209
210    #[test]
211    fn trailer_has_correct_marker_per_style() {
212        assert_eq!(
213            render_trailer(CommentStyle::DoubleSlash, "lib.rs"),
214            "// END lib.rs\n"
215        );
216        assert_eq!(
217            render_trailer(CommentStyle::Hash, "build.toml"),
218            "# END build.toml\n"
219        );
220        assert_eq!(
221            render_trailer(CommentStyle::Xml, "package.csproj"),
222            "<!-- END package.csproj -->\n"
223        );
224    }
225
226    #[test]
227    fn json_prelude_contains_required_phrases_in_first_lines() {
228        let p = render_json_prelude("calc.yml");
229        let lines: Vec<&str> = p.lines().collect();
230        assert!(lines[0].contains("Generated by WeaveFFI"));
231        assert!(lines[0].contains("from calc.yml"));
232        assert!(lines[1].contains("DO NOT EDIT"));
233        assert!(lines[2].contains("To regenerate"));
234        for line in &lines {
235            assert!(line.starts_with("  "));
236            assert!(line.ends_with(','));
237        }
238    }
239}
weaveffi_core/utils.rs

weaveffi_core/
utils.rs
