From 55193d6d80f26ecf8246686301bcb884d7fcd566 Mon Sep 17 00:00:00 2001
From: Jakub Strojewski <jakub.strojewski@gmail.com>
Date: Tue, 19 Nov 2024 14:50:33 +0000
Subject: [PATCH] Make null param error more informative (#809)

---
 .../core/src/main/scala/doobie/util/put.scala |  4 ++--
 .../test/scala/doobie/util/WriteSuite.scala   | 23 +++++++++++++++++++
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/modules/core/src/main/scala/doobie/util/put.scala b/modules/core/src/main/scala/doobie/util/put.scala
index 2588c8ce9..2d4f8d3dd 100644
--- a/modules/core/src/main/scala/doobie/util/put.scala
+++ b/modules/core/src/main/scala/doobie/util/put.scala
@@ -56,7 +56,7 @@ sealed abstract class Put[A](
     ) {}
 
   def unsafeSetNonNullable(ps: PreparedStatement, n: Int, a: A): Unit =
-    if (a == null) sys.error("oops, null")
+    if (a == null) sys.error("Expected non-nullable param. Use Option to describe nullable values.")
     else put.fi.apply(ps, n, (put.k(a)))
 
   def unsafeSetNullable(ps: PreparedStatement, n: Int, oa: Option[A]): Unit =
@@ -66,7 +66,7 @@ sealed abstract class Put[A](
     }
 
   def unsafeUpdateNonNullable(rs: ResultSet, n: Int, a: A): Unit =
-    if (a == null) sys.error("oops, null")
+    if (a == null) sys.error("Expected non-nullable param. Use Option to describe nullable values.")
     else update.fi.apply(rs, n, (update.k(a)))
 
   def unsafeUpdateNullable(rs: ResultSet, n: Int, oa: Option[A]): Unit =
diff --git a/modules/core/src/test/scala/doobie/util/WriteSuite.scala b/modules/core/src/test/scala/doobie/util/WriteSuite.scala
index f90cdf885..6e75b6f59 100644
--- a/modules/core/src/test/scala/doobie/util/WriteSuite.scala
+++ b/modules/core/src/test/scala/doobie/util/WriteSuite.scala
@@ -122,4 +122,27 @@ class WriteSuite extends munit.FunSuite with WriteSuitePlatform {
       .unsafeRunSync()
   }
 
+  test("Write should yield correct error when Some(null) inserted") {
+    interceptMessage[RuntimeException]("Expected non-nullable param. Use Option to describe nullable values.") {
+      testNullPut(("a", Some(null)))
+    }
+  }
+
+  test("Write should yield correct error when null inserted into non-nullable field") {
+    interceptMessage[RuntimeException]("Expected non-nullable param. Use Option to describe nullable values.") {
+      testNullPut((null, Some("b")))
+    }
+  }
+
+  private def testNullPut(input: (String, Option[String])): Int = {
+    import doobie.implicits.*
+
+    (for {
+      _ <- sql"create temp table t0 (a text, b text null)".update.run
+      n <- Update[(String, Option[String])]("insert into t0 (a, b) values (?, ?)").run(input)
+    } yield n)
+      .transact(xa)
+      .unsafeRunSync()
+  }
+
 }