fix: preserve learned patterns and source analysis semantics (#54)

Co-authored-by: Mark Stuart <mstuart@users.noreply.github.com>

Author: mstuart

src/git/decision_parser.rs

@@ -39,22 +39,23 @@ impl DecisionParser {
     pub fn parse_message(&self, message: &str) -> Vec<Decision> {
         let mut decisions = Vec::new();
 
+        let normalized = message.to_lowercase();
         // Check if message contains decision keywords
         let has_decision = self
             .decision_keywords
             .iter()
-            .any(|re| re.is_match(&message.to_lowercase()));
+            .any(|re| re.is_match(&normalized));
 
         if !has_decision {
             return decisions;
         }
 
         // Extract decision type
-        let decision_type = if message.contains("migrat") {
+        let decision_type = if normalized.contains("migrat") {
             "migration"
-        } else if message.contains("arch:") || message.contains("architecture") {
+        } else if normalized.contains("arch:") || normalized.contains("architecture") {
             "architecture"
-        } else if message.contains("refactor:") {
+        } else if normalized.contains("refactor:") {
             "refactoring"
         } else {
             "general"
@@ -86,7 +87,7 @@ impl DecisionParser {
 
 fn extract_migration_pair(message: &str) -> (Option<String>, String) {
     // Pattern: "from X to Y" or "migrate from X to Y"
-    let from_to_re = Regex::new(r"from\s+(\w+)\s+to\s+(\w+)").unwrap();
+    let from_to_re = Regex::new(r"(?i)from\s+(\w+)\s+to\s+(\w+)").unwrap();
 
     if let Some(caps) = from_to_re.captures(message) {
         let from = caps.get(1).map(|m| m.as_str().to_string());

src/graph/analyzer.rs

@@ -51,8 +51,10 @@ fn source_aliases(file_path: &str) -> Vec<String> {
     ) {
         aliases.push(path.with_extension("").to_string_lossy().into_owned());
     }
-    if matches!(extension, Some("ts" | "tsx" | "js"))
-        && path.file_stem().and_then(|stem| stem.to_str()) == Some("index")
+    if (matches!(extension, Some("ts" | "tsx" | "js"))
+        && path.file_stem().and_then(|stem| stem.to_str()) == Some("index"))
+        || (extension == Some("rs")
+            && path.file_stem().and_then(|stem| stem.to_str()) == Some("mod"))
     {
         if let Some(parent) = path.parent() {
             aliases.push(parent.to_string_lossy().into_owned());
@@ -168,7 +170,7 @@ impl DependencyGraph {
                 return self.node_map.get(&with_ext).copied();
             }
         }
-        for ext in &["/index.ts", "/index.js", "/index.tsx"] {
+        for ext in &["/index.ts", "/index.js", "/index.tsx", "/mod.rs"] {
             let with_index = format!("{}{}", resolved, ext);
             if self.source_paths.contains(&with_index) {
                 return self.node_map.get(&with_index).copied();
@@ -315,7 +317,8 @@ impl DependencyGraph {
             return normalize_path(&joined.to_string_lossy());
         }
 
-        import_path.to_string()
+        let joined = source_dir.join(source_stem).join(import_path);
+        normalize_path(&joined.to_string_lossy())
     }
 
     /// What does this file depend on? (direct)

src/sessions/patterns.rs

@@ -45,20 +45,11 @@ impl PatternLibrary {
 
     /// Record an observation of a pattern key.
     pub fn observe(&mut self, key: &str) {
-        *self.observations.entry(key.to_string()).or_insert(0) += 1;
-    }
-
-    /// Record an observation with an example.
-    pub fn observe_with_example(&mut self, key: &str, example: &str) {
-        self.observe(key);
-
-        let count = *self.observations.get(key).unwrap_or(&1);
+        let count = self.observations.entry(key.to_string()).or_insert(0);
+        *count += 1;
+        let count = *count;
         let confidence = Self::calc_confidence(count);
-
         if let Some(pattern) = self.patterns.iter_mut().find(|p| p.key == key) {
-            if pattern.examples.len() < 10 {
-                pattern.examples.push(example.to_string());
-            }
             pattern.observation_count = count;
             pattern.confidence = confidence;
         } else {
@@ -67,13 +58,23 @@ impl PatternLibrary {
                 pattern_type,
                 key: key.to_string(),
                 description,
-                observation_count: 1,
-                confidence: 0.1,
-                examples: vec![example.to_string()],
+                observation_count: count,
+                confidence,
+                examples: Vec::new(),
             });
         }
     }
 
+    /// Record an observation with an example.
+    pub fn observe_with_example(&mut self, key: &str, example: &str) {
+        self.observe(key);
+        if let Some(pattern) = self.patterns.iter_mut().find(|p| p.key == key) {
+            if pattern.examples.len() < 10 {
+                pattern.examples.push(example.to_string());
+            }
+        }
+    }
+
     fn classify_pattern(&self, key: &str) -> (PatternType, String) {
         if key.starts_with("naming:") {
             (

tests/nov2_regressions.rs

@@ -0,0 +1,49 @@
+use code_memory::git::decision_parser::DecisionParser;
+use code_memory::graph::analyzer::DependencyGraph;
+use code_memory::sessions::PatternLibrary;
+
+#[test]
+fn migration_keywords_are_case_insensitive_without_losing_technology_case() {
+    let decisions = DecisionParser::new()
+        .parse_message("Decided to Migrate FROM REST TO GraphQL\nKeep typed queries.");
+    assert_eq!(decisions.len(), 1);
+    assert_eq!(decisions[0].decision_type, "migration");
+    assert_eq!(decisions[0].from.as_deref(), Some("REST"));
+    assert_eq!(decisions[0].to, "GraphQL");
+}
+
+#[test]
+fn plain_observations_are_visible_to_pattern_queries() {
+    let mut library = PatternLibrary::new();
+    for _ in 0..6 {
+        library.observe("naming:rust:snake_case");
+    }
+    let patterns = library.confident_patterns(0.5);
+    assert_eq!(patterns.len(), 1);
+    assert_eq!(patterns[0].observation_count, 6);
+    assert!(patterns[0].examples.is_empty());
+    library.observe_with_example("naming:rust:snake_case", "fn hello_world()");
+    assert_eq!(library.all_patterns()[0].observation_count, 7);
+    assert_eq!(library.all_patterns()[0].examples, ["fn hello_world()"]);
+}
+
+#[test]
+fn rust_child_modules_resolve_in_flat_and_directory_layouts() {
+    for (parent, child) in [
+        ("src/foo.rs", "src/foo/child.rs"),
+        ("src/foo/mod.rs", "src/foo/child.rs"),
+        ("src/lib.rs", "src/child/mod.rs"),
+    ] {
+        for child_first in [false, true] {
+            let mut graph = DependencyGraph::new();
+            if child_first {
+                graph.add_file(child, "pub fn helper() {}\n");
+            }
+            graph.add_file(parent, "mod child;\n");
+            if !child_first {
+                graph.add_file(child, "pub fn helper() {}\n");
+            }
+            assert_eq!(graph.depends_on(parent), [child], "{parent} -> {child}");
+        }
+    }
+}