From 22f46863f4f4658683ceb9daaaa0fa08a47373e4 Mon Sep 17 00:00:00 2001
From: Hanusz Leszek <leszek.hanusz@gmail.com>
Date: Sun, 10 Apr 2022 16:12:20 +0200
Subject: [PATCH] Represent serialized floats to approximately python float
 precision

---
 gql/dsl.py                 |  7 +++++--
 tests/starwars/test_dsl.py | 16 ++++++++++++++++
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/gql/dsl.py b/gql/dsl.py
index 634c10cb..26b9f426 100644
--- a/gql/dsl.py
+++ b/gql/dsl.py
@@ -106,10 +106,13 @@ def ast_from_serialized_value_untyped(serialized: Any) -> Optional[ValueNode]:
         return BooleanValueNode(value=serialized)
 
     if isinstance(serialized, int):
-        return IntValueNode(value=f"{serialized:d}")
+        return IntValueNode(value=str(serialized))
 
     if isinstance(serialized, float) and isfinite(serialized):
-        return FloatValueNode(value=f"{serialized:g}")
+        value = str(serialized)
+        if value.endswith(".0"):
+            value = value[:-2]
+        return FloatValueNode(value=value)
 
     if isinstance(serialized, str):
         return StringValueNode(value=serialized)
diff --git a/tests/starwars/test_dsl.py b/tests/starwars/test_dsl.py
index 50f5449c..c0f2b441 100644
--- a/tests/starwars/test_dsl.py
+++ b/tests/starwars/test_dsl.py
@@ -1,6 +1,8 @@
 import pytest
 from graphql import (
+    FloatValueNode,
     GraphQLError,
+    GraphQLFloat,
     GraphQLID,
     GraphQLInt,
     GraphQLList,
@@ -87,6 +89,20 @@ def test_ast_from_value_with_non_null_type_and_none():
     assert "Received Null value for a Non-Null type Int." in str(exc_info.value)
 
 
+def test_ast_from_value_float_precision():
+
+    # Checking precision of float serialization
+    # See https://github.com/graphql-python/graphql-core/pull/164
+
+    assert ast_from_value(123456789.01234567, GraphQLFloat) == FloatValueNode(
+        value="123456789.01234567"
+    )
+
+    assert ast_from_value(1.1, GraphQLFloat) == FloatValueNode(value="1.1")
+
+    assert ast_from_value(123.0, GraphQLFloat) == FloatValueNode(value="123")
+
+
 def test_ast_from_serialized_value_untyped_typeerror():
     with pytest.raises(TypeError) as exc_info:
         ast_from_serialized_value_untyped(GraphQLInt)