Fix bug introduced when removing brace escaping

Fixes #4.

Author: kyrias

CHANGELOG.md

@@ -0,0 +1,12 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+### Fixed
+
+- Fixed bug introduced when removing brace escaping support that lead to out-of-bound panics when two bound parameter references were too far apart. ([#4](https://github.com/kyrias/sqlx-conditional-queries/issues/4))

core/src/expand.rs

@@ -174,8 +174,8 @@ fn expand_compile_time_bindings(
         let mut fragment_str = fragment_string.as_str();
 
         while let Some(start_of_binding) = fragment_str.find('{') {
-            // Otherwise we've hit either a compile-time or a run-time binding, so first we
-            // push any prefix before the binding.
+            // We've hit either a compile-time or a run-time binding, so first we push any prefix
+            // before the binding.
             if !fragment_str[..start_of_binding].is_empty() {
                 expanded_fragments.push(syn::LitStr::new(
                     &fragment_str[..start_of_binding],
@@ -191,7 +191,7 @@ fn expand_compile_time_bindings(
                 return Err(ExpandError::MissingBindingClosingBrace(fragment.span()));
             };
 
-            if fragment_str[start_of_binding..].chars().nth(1) == Some('#') {
+            if fragment_str.chars().nth(1) == Some('#') {
                 // If the binding is a compile-time binding, expand it.
                 let binding_name = &fragment_str[2..end_of_binding];
                 if let Some(binding) = compile_time_bindings.get(binding_name) {

core/tests/lib.rs

@@ -0,0 +1 @@
+mod regressions;

core/tests/regressions/issue_4.rs

@@ -0,0 +1,14 @@
+#[test]
+fn regression_test_() {
+    let input: proc_macro2::TokenStream = r##"
+            SomeType,
+            r#"{#a}______{c}"#,
+            #a = match _ {
+                _ => "b",
+            },
+        "##
+    .parse()
+    .unwrap();
+
+    sqlx_conditional_queries_core::conditional_query_as(input).unwrap();
+}

core/tests/regressions/mod.rs

@@ -0,0 +1 @@
+mod issue_4;