From bb4f8b1c668c1ef60ab00282192e6a48fc99472e Mon Sep 17 00:00:00 2001
From: Henry Su <henrysu4707@gmail.com>
Date: Sun, 23 Aug 2026 11:42:55 -0500
Subject: [PATCH] fix: retrieve the zero-argument function overload when args
 is empty

functions.retrieve skipped the proargtypes filter for args: [], so overloaded names could return the wrong signature.
---
 src/lib/sql/functions.sql.ts | 12 +++++-------
 test/lib/functions.ts        | 16 ++++++++++++++++
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/src/lib/sql/functions.sql.ts b/src/lib/sql/functions.sql.ts
index ea41d5e1..b51054ce 100644
--- a/src/lib/sql/functions.sql.ts
+++ b/src/lib/sql/functions.sql.ts
@@ -38,10 +38,9 @@ with functions as (
     ${
       props.args === undefined
         ? ''
-        : props.args.length > 0
-          ? `p.proargtypes::text = ${
-              props.args.length
-                ? `(
+        : `p.proargtypes::text = ${
+            props.args.length > 0
+              ? `(
           SELECT STRING_AGG(type_oid::text, ' ') FROM (
             SELECT (
               split_args.arr[
@@ -60,9 +59,8 @@ with functions as (
             ) AS split_args
           ) args
     )`
-                : "''"
-            } AND`
-          : ''
+              : "''"
+          } AND`
     }
     p.prokind = 'f'
 )
diff --git a/test/lib/functions.ts b/test/lib/functions.ts
index ce26e078..7d0d63a6 100644
--- a/test/lib/functions.ts
+++ b/test/lib/functions.ts
@@ -531,3 +531,19 @@ test('retrieve function by args filter - function with no arguments', async () =
   })
   expect(res.error).toBeNull()
 })
+
+test('retrieve function by args filter - zero-argument overload among polymorphic functions', async () => {
+  const res = await pgMeta.functions.retrieve({
+    schema: 'public',
+    name: 'polymorphic_function_with_no_params_or_unnamed',
+    args: [],
+  })
+  expect(res.error).toBeNull()
+  expect(res.data).toMatchObject({
+    name: 'polymorphic_function_with_no_params_or_unnamed',
+    schema: 'public',
+    argument_types: '',
+    args: [],
+    return_type: 'integer',
+  })
+})