From fc70cea9b08afc13314012965791882709bed834 Mon Sep 17 00:00:00 2001
From: Greg Shuflin <greg@everydayimshuflin.com>
Date: Mon, 3 Jun 2024 22:07:39 -0500
Subject: [PATCH] analyzer: definition tracker

---
 src/analyzer.rs | 69 +++++++++++++++++++++++++++----------------------
 1 file changed, 38 insertions(+), 31 deletions(-)

diff --git a/src/analyzer.rs b/src/analyzer.rs
index e384f9a..75696f7 100644
--- a/src/analyzer.rs
+++ b/src/analyzer.rs
@@ -1,5 +1,39 @@
 use {super::*, CompileErrorKind::*};
 
+#[derive(Default)]
+struct DefinitionTracker<'src> {
+  definitions: HashMap<&'src str, (&'static str, Name<'src>)>,
+}
+
+impl<'src> DefinitionTracker<'src> {
+  fn define(
+    &mut self,
+    name: Name<'src>,
+    second_type: &'static str,
+    duplicates_allowed: bool,
+  ) -> CompileResult<'src> {
+    if let Some((first_type, original)) = self.definitions.get(name.lexeme()) {
+      if !(*first_type == second_type && duplicates_allowed) {
+        let (original, redefinition) = if name.line < original.line {
+          (name, *original)
+        } else {
+          (*original, name)
+        };
+
+        return Err(redefinition.token.error(Redefinition {
+          first_type,
+          second_type,
+          name: name.lexeme(),
+          first: original.line,
+        }));
+      }
+    }
+
+    self.definitions.insert(name.lexeme(), (second_type, name));
+    Ok(())
+  }
+}
+
 #[derive(Default)]
 pub(crate) struct Analyzer<'src> {
   assignments: Table<'src, Assignment<'src>>,
@@ -19,45 +53,18 @@ impl<'src> Analyzer<'src> {
   ) -> CompileResult<'src, Justfile<'src>> {
     let mut analyzer = Self::default();
 
+    let mut definitions = DefinitionTracker::default();
     let mut unprocessed_recipes = Vec::new();
     let mut unprocessed_assignments = Vec::new();
 
     let mut stack = Vec::new();
     stack.push(asts.get(root).unwrap());
 
-    let mut definitions: HashMap<&str, (&'static str, Name)> = HashMap::new();
-
-    let mut define = |name: Name<'src>,
-                      second_type: &'static str,
-                      duplicates_allowed: bool|
-     -> CompileResult<'src> {
-      if let Some((first_type, original)) = definitions.get(name.lexeme()) {
-        if !(*first_type == second_type && duplicates_allowed) {
-          let (original, redefinition) = if name.line < original.line {
-            (name, *original)
-          } else {
-            (*original, name)
-          };
-
-          return Err(redefinition.token.error(Redefinition {
-            first_type,
-            second_type,
-            name: name.lexeme(),
-            first: original.line,
-          }));
-        }
-      }
-
-      definitions.insert(name.lexeme(), (second_type, name));
-
-      Ok(())
-    };
-
     while let Some(ast) = stack.pop() {
       for item in &ast.items {
         match item {
           Item::Alias(alias) => {
-            define(alias.name, "alias", false)?;
+            definitions.define(alias.name, "alias", false)?;
             Self::analyze_alias(alias)?;
             analyzer.aliases.insert(alias.clone());
           }
@@ -72,7 +79,7 @@ impl<'src> Analyzer<'src> {
           }
           Item::Module { absolute, name, .. } => {
             if let Some(absolute) = absolute {
-              define(*name, "module", false)?;
+              definitions.define(*name, "module", false)?;
               analyzer
                 .modules
                 .insert(Self::analyze(loaded, paths, asts, absolute, Some(*name))?);
@@ -119,7 +126,7 @@ impl<'src> Analyzer<'src> {
     let recipes = {
       let mut recipe_table: Table<'src, UnresolvedRecipe<'src>> = Table::default();
       for recipe in unprocessed_recipes {
-        define(recipe.name, "recipe", settings.allow_duplicate_recipes)?;
+        definitions.define(recipe.name, "recipe", settings.allow_duplicate_recipes)?;
         if recipe_table
           .get(recipe.name.lexeme())
           .map_or(true, |original| recipe.file_depth <= original.file_depth)