feat(lints): add quote dependency and improve variable name detection

Use `quote` token stream matching instead of debug formatting
to detect variable references in `unnecessary_render_result_creation`,
fixing false positives from string-based matching.

5 files changed, 42 insertions, 48 deletions

diff --git a/mingling_cli/Cargo.lock b/mingling_cli/Cargo.lock
index 6d34351..e617d0a 100644
--- a/mingling_cli/Cargo.lock
+++ b/mingling_cli/Cargo.lock
@@ -254,6 +254,7 @@ dependencies = [
  "just_template",
  "mingling",
  "proc-macro2",
+ "quote",
  "serde",
  "serde_json",
  "syn 3.0.2",
diff --git a/mingling_cli/Cargo.toml b/mingling_cli/Cargo.toml
index ab51d9e..5b36c6b 100644
--- a/mingling_cli/Cargo.toml
+++ b/mingling_cli/Cargo.toml
@@ -40,6 +40,7 @@ annotate-snippets = "0.12.16"
 # Code analyze
 proc-macro2 = { version = "1.0.107", features = ["span-locations"] }
 syn = { version = "3.0.2", features = ["full", "extra-traits"] }
+quote = "1.0.47"
 
 # Configure & Serialization
 serde = { version = "1.0.229", features = ["derive"] }
diff --git a/mingling_cli/src/lints.rs b/mingling_cli/src/lints.rs
index 8fab924..1db4c6b 100644
--- a/mingling_cli/src/lints.rs
+++ b/mingling_cli/src/lints.rs
@@ -12,21 +12,17 @@ pub fn run_all_lints(file: &syn::File, source: &str) -> Vec<MlintReport> {
     let mut reports = vec![];
     for item in &file.items {
         if let syn::Item::Fn(f) = item {
-            // Check item-level #[mlint(allow/warn/deny(template_linter))]
             let skip = get_mlint_override(&f.attrs, "template_linter") == Some(MlintLevelOverride::Allow);
             if !skip {
                 let mut rs = template_linter::linter(f.clone(), source);
-                // Apply deny override at item level
                 if get_mlint_override(&f.attrs, "template_linter") == Some(MlintLevelOverride::Deny) {
                     for r in &mut rs { r.level = MlintLevel::Error; }
                 }
                 reports.extend(rs);
             }
-            // Check item-level #[mlint(allow/warn/deny(unnecessary_render_result_creation))]
             let skip = get_mlint_override(&f.attrs, "unnecessary_render_result_creation") == Some(MlintLevelOverride::Allow);
             if !skip {
                 let mut rs = unnecessary_render_result_creation::linter(f.clone(), source);
-                // Apply deny override at item level
                 if get_mlint_override(&f.attrs, "unnecessary_render_result_creation") == Some(MlintLevelOverride::Deny) {
                     for r in &mut rs { r.level = MlintLevel::Error; }
                 }
@@ -35,45 +31,38 @@ pub fn run_all_lints(file: &syn::File, source: &str) -> Vec<MlintReport> {
 
         }
     }
-    // Apply file-level #![mlint(allow/warn/deny(...))] overrides
     for r in &mut reports {
         let name = &r.lint_code;
         if let Some(override_level) = get_mlint_override(&file.attrs, name) {
             match override_level {
-                MlintLevelOverride::Allow => {
-                    // remove by marking; filtered below
-                    r.level = MlintLevel::Help; // sentinel: filtered out
-                }
-                MlintLevelOverride::Deny => {
-                    r.level = MlintLevel::Error;
-                }
+                MlintLevelOverride::Allow => r.level = MlintLevel::Help,
+                MlintLevelOverride::Deny => r.level = MlintLevel::Error,
                 MlintLevelOverride::Warn => {
-                    if r.level != MlintLevel::Error {
-                        r.level = MlintLevel::Warning;
-                    }
+                    if r.level != MlintLevel::Error { r.level = MlintLevel::Warning; }
                 }
             }
         }
     }
-    // Remove allowed reports (sentinel = Help)
     reports.retain(|r| r.level != MlintLevel::Help);
     reports
 }
 
 #[macro_export]
 macro_rules! assert_detected {
-    ($linter:expr, $ast_type:ty => $code:tt) => {
-        // Parse the string into a syn::ItemFn
-        let ast: $ast_type = syn::parse_str(&stringify!($code)).unwrap();
-        assert!(!$linter(ast, &stringify!($code).to_string()).is_empty());
+    ($linter:expr, $ast_type:ty => { $($code:tt)* }) => {
+        // $($code:tt)* captures tokens INSIDE the braces, not including the braces
+        // e.g. `fn foo() { ... }` — exactly what syn::ItemFn expects
+        let source = stringify!($($code)*);
+        let ast: $ast_type = syn::parse_str(&source).unwrap();
+        assert!(!$linter(ast, &source).is_empty());
     };
 }
 
 #[macro_export]
 macro_rules! assert_not_detected {
-    ($linter:expr, $ast_type:ty => $code:tt) => {
-        // Parse the string into a syn::ItemFn
-        let ast: $ast_type = syn::parse_str(&stringify!($code)).unwrap();
-        assert!($linter(ast, &stringify!($code).to_string()).is_empty());
+    ($linter:expr, $ast_type:ty => { $($code:tt)* }) => {
+        let source = stringify!($($code)*);
+        let ast: $ast_type = syn::parse_str(&source).unwrap();
+        assert!($linter(ast, &source).is_empty());
     };
 }
\ No newline at end of file
diff --git a/mingling_cli/src/lints/unnecessary_render_result_creation.rs b/mingling_cli/src/lints/unnecessary_render_result_creation.rs
index 06c47d9..03f81d2 100644
--- a/mingling_cli/src/lints/unnecessary_render_result_creation.rs
+++ b/mingling_cli/src/lints/unnecessary_render_result_creation.rs
@@ -15,6 +15,7 @@
 //! Default: `warn`
 
 use crate::linter::mlint_report::{MlintLevel, MlintReport};
+use quote::ToTokens;
 
 pub fn linter(ast: syn::ItemFn, source: &str) -> Vec<MlintReport> {
     if !has_renderer_attr(&ast) {
@@ -169,8 +170,19 @@ fn check_stmt_usage(stmt: &syn::Stmt, r_name: &str, print_count: &mut usize) ->
         }
     }
 
-    let s = format!("{stmt:#?}");
-    !s.contains(&format!("\"{r_name}\""))
+    // Any other reference to r → not allowed
+    // Check the token stream for the variable name
+    let ts_string = stmt.to_token_stream().to_string();
+    if ts_string.contains(&format!("({r_name})"))
+        || ts_string.contains(&format!(" {r_name})"))
+        || ts_string.contains(&format!("(&mut {r_name})"))
+        || ts_string.contains(&format!("&{r_name}"))
+        || ts_string.contains(&format!("move {r_name}"))
+        || ts_string.contains(&format!(",{r_name},"))
+    {
+        return false;
+    }
+    true
 }
 
 #[cfg(test)]
diff --git a/mingling_cli/tmpls/lints.tmpl b/mingling_cli/tmpls/lints.tmpl
index fae1126..3b20ed4 100644
--- a/mingling_cli/tmpls/lints.tmpl
+++ b/mingling_cli/tmpls/lints.tmpl
@@ -12,11 +12,9 @@ pub fn run_all_lints(file: &syn::File, source: &str) -> Vec<MlintReport> {
 >>>>>>>>>> calls;
 
 @@@ >>> calls
-            // Check item-level #[mlint(allow/warn/deny(<<<name>>>))]
             let skip = get_mlint_override(&f.attrs, "<<<name>>>") == Some(MlintLevelOverride::Allow);
             if !skip {
                 let mut rs = <<<name>>>::linter(f.clone(), source);
-                // Apply deny override at item level
                 if get_mlint_override(&f.attrs, "<<<name>>>") == Some(MlintLevelOverride::Deny) {
                     for r in &mut rs { r.level = MlintLevel::Error; }
                 }
@@ -25,46 +23,39 @@ pub fn run_all_lints(file: &syn::File, source: &str) -> Vec<MlintReport> {
 @@@ <<<
         }
     }
-    // Apply file-level #![mlint(allow/warn/deny(...))] overrides
     for r in &mut reports {
         let name = &r.lint_code;
         if let Some(override_level) = get_mlint_override(&file.attrs, name) {
             match override_level {
-                MlintLevelOverride::Allow => {
-                    // remove by marking; filtered below
-                    r.level = MlintLevel::Help; // sentinel: filtered out
-                }
-                MlintLevelOverride::Deny => {
-                    r.level = MlintLevel::Error;
-                }
+                MlintLevelOverride::Allow => r.level = MlintLevel::Help,
+                MlintLevelOverride::Deny => r.level = MlintLevel::Error,
                 MlintLevelOverride::Warn => {
-                    if r.level != MlintLevel::Error {
-                        r.level = MlintLevel::Warning;
-                    }
+                    if r.level != MlintLevel::Error { r.level = MlintLevel::Warning; }
                 }
             }
         }
     }
-    // Remove allowed reports (sentinel = Help)
     reports.retain(|r| r.level != MlintLevel::Help);
     reports
 }
 
 #[macro_export]
 macro_rules! assert_detected {
-    ($linter:expr, $ast_type:ty => $code:tt) => {
-        // Parse the string into a syn::ItemFn
-        let ast: $ast_type = syn::parse_str(&stringify!($code)).unwrap();
-        assert!(!$linter(ast, &stringify!($code).to_string()).is_empty());
+    ($linter:expr, $ast_type:ty => { $($code:tt)* }) => {
+        // $($code:tt)* captures tokens INSIDE the braces, not including the braces
+        // e.g. `fn foo() { ... }` — exactly what syn::ItemFn expects
+        let source = stringify!($($code)*);
+        let ast: $ast_type = syn::parse_str(&source).unwrap();
+        assert!(!$linter(ast, &source).is_empty());
     };
 }
 
 #[macro_export]
 macro_rules! assert_not_detected {
-    ($linter:expr, $ast_type:ty => $code:tt) => {
-        // Parse the string into a syn::ItemFn
-        let ast: $ast_type = syn::parse_str(&stringify!($code)).unwrap();
-        assert!($linter(ast, &stringify!($code).to_string()).is_empty());
+    ($linter:expr, $ast_type:ty => { $($code:tt)* }) => {
+        let source = stringify!($($code)*);
+        let ast: $ast_type = syn::parse_str(&source).unwrap();
+        assert!($linter(ast, &source).is_empty());
     };
 }