From 6bcf8203753117cfffb4b9a0eaa8d96aa2f3f53f Mon Sep 17 00:00:00 2001
From: Don Olmstead <me@donolmstead.dev>
Date: Tue, 18 Aug 2026 14:49:47 -0700
Subject: [PATCH] Support primary constructors

Change the check for the `_` value constructor to support `new _()`.
---
 CHANGELOG.md                                          |  6 +++++-
 built_value_generator/lib/src/value_source_class.dart | 11 +++++++----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 56236f4a..08818e18 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+# 8.12.8
+
+- Support generating from classes using primary constructors.
+
 # 8.12.7
 
 - Allow `analyzer 13.0.0` and `analyzer 14.0.0`
@@ -200,7 +204,7 @@
 
 # 8.3.1
 
-- Fix generation support for optional generic bounds, e.g. 
+- Fix generation support for optional generic bounds, e.g.
   `class Foo<T extends Object?>`.
 - Fix generation for classes with names starting `$`.
 - Ignore lint `unnecessary_lambdas` in generated code.
diff --git a/built_value_generator/lib/src/value_source_class.dart b/built_value_generator/lib/src/value_source_class.dart
index bc187535..d125625c 100644
--- a/built_value_generator/lib/src/value_source_class.dart
+++ b/built_value_generator/lib/src/value_source_class.dart
@@ -669,6 +669,11 @@ abstract class ValueSourceClass
       }
 
       final expectedConstructor = '$name._()';
+      bool constructorCheck(ConstructorDeclaration c) {
+        final check = c.typeName != null ? expectedConstructor : '_()';
+        return c.toSource().contains(check);
+      }
+
       if (valueClassConstructors.isEmpty) {
         result.add(
           GeneratorError(
@@ -683,7 +688,7 @@ abstract class ValueSourceClass
       } else if (valueClassConstructors.length > 1) {
         var found = false;
         for (var constructor in valueClassConstructors) {
-          if (constructor.toSource().contains(expectedConstructor)) {
+          if (constructorCheck(constructor)) {
             found = true;
           } else {
             result.add(
@@ -709,9 +714,7 @@ abstract class ValueSourceClass
             ),
           );
         }
-      } else if (!(valueClassConstructors.single.toSource().contains(
-            expectedConstructor,
-          ))) {
+      } else if (!constructorCheck(valueClassConstructors.single)) {
         result.add(
           GeneratorError(
             (b) => b