normalize_languages/

diff.rs

//! Diff/patch file support.

use crate::external_packages::ResolvedPackage;
use crate::{Export, Import, Language, Symbol, SymbolKind, Visibility, VisibilityMechanism};
use std::path::{Path, PathBuf};
use tree_sitter::Node;

/// Diff language support.
pub struct Diff;

impl Language for Diff {
    fn name(&self) -> &'static str {
        "Diff"
    }
    fn extensions(&self) -> &'static [&'static str] {
        &["diff", "patch"]
    }
    fn grammar_name(&self) -> &'static str {
        "diff"
    }

    fn has_symbols(&self) -> bool {
        true
    }

    fn container_kinds(&self) -> &'static [&'static str] {
        &["file_change"]
    }

    fn function_kinds(&self) -> &'static [&'static str] {
        &[]
    }
    fn type_kinds(&self) -> &'static [&'static str] {
        &[]
    }
    fn import_kinds(&self) -> &'static [&'static str] {
        &[]
    }

    fn public_symbol_kinds(&self) -> &'static [&'static str] {
        &["file_change"]
    }

    fn visibility_mechanism(&self) -> VisibilityMechanism {
        VisibilityMechanism::AllPublic
    }

    fn extract_public_symbols(&self, node: &Node, content: &str) -> Vec<Export> {
        if node.kind() != "file_change" {
            return Vec::new();
        }

        let text = &content[node.byte_range()];
        // Extract filename from diff header
        for prefix in &["--- ", "+++ ", "diff --git "] {
            if text.starts_with(prefix) {
                let name = text[prefix.len()..]
                    .split_whitespace()
                    .next()
                    .map(|s| s.trim_start_matches("a/").trim_start_matches("b/"))
                    .unwrap_or("unknown");
                return vec![Export {
                    name: name.to_string(),
                    kind: SymbolKind::Module,
                    line: node.start_position().row + 1,
                }];
            }
        }

        Vec::new()
    }

    fn scope_creating_kinds(&self) -> &'static [&'static str] {
        &["file_change"]
    }

    fn control_flow_kinds(&self) -> &'static [&'static str] {
        &[]
    }
    fn complexity_nodes(&self) -> &'static [&'static str] {
        &[]
    }
    fn nesting_nodes(&self) -> &'static [&'static str] {
        &["file_change"]
    }

    fn signature_suffix(&self) -> &'static str {
        ""
    }

    fn extract_function(
        &self,
        _node: &Node,
        _content: &str,
        _in_container: bool,
    ) -> Option<Symbol> {
        None
    }

    fn extract_container(&self, node: &Node, content: &str) -> Option<Symbol> {
        if node.kind() != "file_change" {
            return None;
        }

        let text = &content[node.byte_range()];
        let first_line = text.lines().next().unwrap_or(text);

        // Extract filename from diff header
        let name = first_line
            .split_whitespace()
            .find(|s| s.contains('/') || s.contains('.'))
            .map(|s| s.trim_start_matches("a/").trim_start_matches("b/"))
            .unwrap_or("unknown");

        Some(Symbol {
            name: name.to_string(),
            kind: SymbolKind::Module,
            signature: first_line.to_string(),
            docstring: None,
            attributes: Vec::new(),
            start_line: node.start_position().row + 1,
            end_line: node.end_position().row + 1,
            visibility: Visibility::Public,
            children: Vec::new(),
            is_interface_impl: false,
            implements: Vec::new(),
        })
    }

    fn extract_type(&self, _node: &Node, _content: &str) -> Option<Symbol> {
        None
    }
    fn extract_docstring(&self, _node: &Node, _content: &str) -> Option<String> {
        None
    }

    fn extract_attributes(&self, _node: &Node, _content: &str) -> Vec<String> {
        Vec::new()
    }
    fn extract_imports(&self, _node: &Node, _content: &str) -> Vec<Import> {
        Vec::new()
    }

    fn format_import(&self, _import: &Import, _names: Option<&[&str]>) -> String {
        // Diff has no imports
        String::new()
    }

    fn is_public(&self, _node: &Node, _content: &str) -> bool {
        true
    }
    fn get_visibility(&self, _node: &Node, _content: &str) -> Visibility {
        Visibility::Public
    }

    fn is_test_symbol(&self, _symbol: &crate::Symbol) -> bool {
        false
    }

    fn embedded_content(&self, _node: &Node, _content: &str) -> Option<crate::EmbeddedBlock> {
        None
    }

    fn container_body<'a>(&self, _node: &'a Node<'a>) -> Option<Node<'a>> {
        None
    }
    fn body_has_docstring(&self, _body: &Node, _content: &str) -> bool {
        false
    }
    fn node_name<'a>(&self, _node: &Node, _content: &'a str) -> Option<&'a str> {
        None
    }

    fn file_path_to_module_name(&self, path: &Path) -> Option<String> {
        let ext = path.extension()?.to_str()?;
        if !["diff", "patch"].contains(&ext) {
            return None;
        }
        let stem = path.file_stem()?.to_str()?;
        Some(stem.to_string())
    }

    fn module_name_to_paths(&self, module: &str) -> Vec<String> {
        vec![format!("{}.diff", module), format!("{}.patch", module)]
    }

    fn lang_key(&self) -> &'static str {
        "diff"
    }

    fn is_stdlib_import(&self, _: &str, _: &Path) -> bool {
        false
    }
    fn find_stdlib(&self, _: &Path) -> Option<PathBuf> {
        None
    }
    fn resolve_local_import(&self, _: &str, _: &Path, _: &Path) -> Option<PathBuf> {
        None
    }
    fn resolve_external_import(&self, _: &str, _: &Path) -> Option<ResolvedPackage> {
        None
    }
    fn get_version(&self, _: &Path) -> Option<String> {
        None
    }
    fn find_package_cache(&self, _: &Path) -> Option<PathBuf> {
        None
    }
    fn indexable_extensions(&self) -> &'static [&'static str] {
        &["diff", "patch"]
    }
    fn package_sources(&self, _: &Path) -> Vec<crate::PackageSource> {
        Vec::new()
    }

    fn should_skip_package_entry(&self, name: &str, is_dir: bool) -> bool {
        use crate::traits::{has_extension, skip_dotfiles};
        if skip_dotfiles(name) {
            return true;
        }
        !is_dir && !has_extension(name, self.indexable_extensions())
    }

    fn discover_packages(&self, _: &crate::PackageSource) -> Vec<(String, PathBuf)> {
        Vec::new()
    }

    fn package_module_name(&self, entry_name: &str) -> String {
        entry_name
            .strip_suffix(".diff")
            .or_else(|| entry_name.strip_suffix(".patch"))
            .unwrap_or(entry_name)
            .to_string()
    }

    fn find_package_entry(&self, path: &Path) -> Option<PathBuf> {
        if path.is_file() {
            Some(path.to_path_buf())
        } else {
            None
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::validate_unused_kinds_audit;

    #[test]
    fn unused_node_kinds_audit() {
        #[rustfmt::skip]
        let documented_unused: &[&str] = &[
            "block", // Hunk block
        ];
        validate_unused_kinds_audit(&Diff, documented_unused)
            .expect("Diff unused node kinds audit failed");
    }
}