refactor: modularize codebase and add 404 unit tests (#13)

compliance-graph/src/parsers/rust_parser.rs

@@ -363,6 +363,214 @@ impl RustParser {
     }
 }
 
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use compliance_core::traits::graph_builder::LanguageParser;
+    use std::path::PathBuf;
+
+    fn parse_rust(source: &str) -> ParseOutput {
+        let parser = RustParser::new();
+        parser
+            .parse_file(&PathBuf::from("test.rs"), source, "repo1", "build1")
+            .unwrap()
+    }
+
+    #[test]
+    fn test_extract_use_path_simple() {
+        let parser = RustParser::new();
+        assert_eq!(
+            parser.extract_use_path("use std::collections::HashMap;"),
+            Some("std::collections::HashMap".to_string())
+        );
+    }
+
+    #[test]
+    fn test_extract_use_path_nested() {
+        let parser = RustParser::new();
+        assert_eq!(
+            parser.extract_use_path("use crate::models::graph::CodeNode;"),
+            Some("crate::models::graph::CodeNode".to_string())
+        );
+    }
+
+    #[test]
+    fn test_extract_use_path_no_prefix() {
+        let parser = RustParser::new();
+        assert_eq!(parser.extract_use_path("let x = 5;"), None);
+    }
+
+    #[test]
+    fn test_extract_use_path_empty() {
+        let parser = RustParser::new();
+        assert_eq!(parser.extract_use_path(""), None);
+    }
+
+    #[test]
+    fn test_parse_function() {
+        let output = parse_rust("fn hello() {\n    let x = 1;\n}\n");
+        let fn_nodes: Vec<_> = output
+            .nodes
+            .iter()
+            .filter(|n| n.kind == CodeNodeKind::Function)
+            .collect();
+        assert_eq!(fn_nodes.len(), 1);
+        assert_eq!(fn_nodes[0].name, "hello");
+        assert!(fn_nodes[0].qualified_name.contains("hello"));
+    }
+
+    #[test]
+    fn test_parse_struct() {
+        let output = parse_rust("struct Foo {\n    x: i32,\n}\n");
+        let struct_nodes: Vec<_> = output
+            .nodes
+            .iter()
+            .filter(|n| n.kind == CodeNodeKind::Struct)
+            .collect();
+        assert_eq!(struct_nodes.len(), 1);
+        assert_eq!(struct_nodes[0].name, "Foo");
+    }
+
+    #[test]
+    fn test_parse_enum() {
+        let output = parse_rust("enum Color {\n    Red,\n    Blue,\n}\n");
+        let enum_nodes: Vec<_> = output
+            .nodes
+            .iter()
+            .filter(|n| n.kind == CodeNodeKind::Enum)
+            .collect();
+        assert_eq!(enum_nodes.len(), 1);
+        assert_eq!(enum_nodes[0].name, "Color");
+    }
+
+    #[test]
+    fn test_parse_trait() {
+        let output = parse_rust("trait Drawable {\n    fn draw(&self);\n}\n");
+        let trait_nodes: Vec<_> = output
+            .nodes
+            .iter()
+            .filter(|n| n.kind == CodeNodeKind::Trait)
+            .collect();
+        assert_eq!(trait_nodes.len(), 1);
+        assert_eq!(trait_nodes[0].name, "Drawable");
+    }
+
+    #[test]
+    fn test_parse_file_node_always_created() {
+        let output = parse_rust("");
+        let file_nodes: Vec<_> = output
+            .nodes
+            .iter()
+            .filter(|n| n.kind == CodeNodeKind::File)
+            .collect();
+        assert_eq!(file_nodes.len(), 1);
+        assert_eq!(file_nodes[0].language, "rust");
+    }
+
+    #[test]
+    fn test_parse_multiple_functions() {
+        let source = "fn foo() {}\nfn bar() {}\nfn baz() {}\n";
+        let output = parse_rust(source);
+        let fn_nodes: Vec<_> = output
+            .nodes
+            .iter()
+            .filter(|n| n.kind == CodeNodeKind::Function)
+            .collect();
+        assert_eq!(fn_nodes.len(), 3);
+    }
+
+    #[test]
+    fn test_parse_main_is_entry_point() {
+        let output = parse_rust("fn main() {\n    println!(\"hi\");\n}\n");
+        let main_node = output.nodes.iter().find(|n| n.name == "main").unwrap();
+        assert!(main_node.is_entry_point);
+    }
+
+    #[test]
+    fn test_parse_pub_fn_is_entry_point() {
+        let output = parse_rust("pub fn handler() {}\n");
+        let node = output.nodes.iter().find(|n| n.name == "handler").unwrap();
+        assert!(node.is_entry_point);
+    }
+
+    #[test]
+    fn test_parse_private_fn_is_not_entry_point() {
+        let output = parse_rust("fn helper() {}\n");
+        let node = output.nodes.iter().find(|n| n.name == "helper").unwrap();
+        assert!(!node.is_entry_point);
+    }
+
+    #[test]
+    fn test_parse_function_calls_create_edges() {
+        let source = "fn caller() {\n    callee();\n}\nfn callee() {}\n";
+        let output = parse_rust(source);
+        let call_edges: Vec<_> = output
+            .edges
+            .iter()
+            .filter(|e| e.kind == CodeEdgeKind::Calls)
+            .collect();
+        assert!(!call_edges.is_empty());
+        assert!(call_edges.iter().any(|e| e.target.contains("callee")));
+    }
+
+    #[test]
+    fn test_parse_use_declaration_creates_import_edge() {
+        let source = "use std::collections::HashMap;\nfn foo() {}\n";
+        let output = parse_rust(source);
+        let import_edges: Vec<_> = output
+            .edges
+            .iter()
+            .filter(|e| e.kind == CodeEdgeKind::Imports)
+            .collect();
+        assert!(!import_edges.is_empty());
+    }
+
+    #[test]
+    fn test_parse_impl_methods() {
+        let source = "struct Foo {}\nimpl Foo {\n    fn do_thing(&self) {}\n}\n";
+        let output = parse_rust(source);
+        let fn_nodes: Vec<_> = output
+            .nodes
+            .iter()
+            .filter(|n| n.kind == CodeNodeKind::Function)
+            .collect();
+        assert_eq!(fn_nodes.len(), 1);
+        assert_eq!(fn_nodes[0].name, "do_thing");
+        // Method should be qualified under the impl type
+        assert!(fn_nodes[0].qualified_name.contains("Foo"));
+    }
+
+    #[test]
+    fn test_parse_mod_item() {
+        let source = "mod inner {\n    fn nested() {}\n}\n";
+        let output = parse_rust(source);
+        let mod_nodes: Vec<_> = output
+            .nodes
+            .iter()
+            .filter(|n| n.kind == CodeNodeKind::Module)
+            .collect();
+        assert_eq!(mod_nodes.len(), 1);
+        assert_eq!(mod_nodes[0].name, "inner");
+    }
+
+    #[test]
+    fn test_parse_line_numbers() {
+        let source = "fn first() {}\n\n\nfn second() {}\n";
+        let output = parse_rust(source);
+        let first = output.nodes.iter().find(|n| n.name == "first").unwrap();
+        let second = output.nodes.iter().find(|n| n.name == "second").unwrap();
+        assert_eq!(first.start_line, 1);
+        assert!(second.start_line > first.start_line);
+    }
+
+    #[test]
+    fn test_language_and_extensions() {
+        let parser = RustParser::new();
+        assert_eq!(parser.language(), "rust");
+        assert_eq!(parser.extensions(), &["rs"]);
+    }
+}
+
 impl LanguageParser for RustParser {
     fn language(&self) -> &str {
         "rust"