✨ Allow setting unique in Field() for a column (#83)

Co-authored-by: Raphael Gibson <raphael.araujo@estantemagica.com.br>
Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>

tests/test_main.py

@@ -0,0 +1,93 @@
+from typing import Optional
+
+import pytest
+from sqlalchemy.exc import IntegrityError
+from sqlmodel import Field, Session, SQLModel, create_engine
+
+
+def test_should_allow_duplicate_row_if_unique_constraint_is_not_passed(clear_sqlmodel):
+    class Hero(SQLModel, table=True):
+        id: Optional[int] = Field(default=None, primary_key=True)
+        name: str
+        secret_name: str
+        age: Optional[int] = None
+
+    hero_1 = Hero(name="Deadpond", secret_name="Dive Wilson")
+    hero_2 = Hero(name="Deadpond", secret_name="Dive Wilson")
+
+    engine = create_engine("sqlite://")
+
+    SQLModel.metadata.create_all(engine)
+
+    with Session(engine) as session:
+        session.add(hero_1)
+        session.commit()
+        session.refresh(hero_1)
+
+    with Session(engine) as session:
+        session.add(hero_2)
+        session.commit()
+        session.refresh(hero_2)
+
+    with Session(engine) as session:
+        heroes = session.query(Hero).all()
+        assert len(heroes) == 2
+        assert heroes[0].name == heroes[1].name
+
+
+def test_should_allow_duplicate_row_if_unique_constraint_is_false(clear_sqlmodel):
+    class Hero(SQLModel, table=True):
+        id: Optional[int] = Field(default=None, primary_key=True)
+        name: str
+        secret_name: str = Field(unique=False)
+        age: Optional[int] = None
+
+    hero_1 = Hero(name="Deadpond", secret_name="Dive Wilson")
+    hero_2 = Hero(name="Deadpond", secret_name="Dive Wilson")
+
+    engine = create_engine("sqlite://")
+
+    SQLModel.metadata.create_all(engine)
+
+    with Session(engine) as session:
+        session.add(hero_1)
+        session.commit()
+        session.refresh(hero_1)
+
+    with Session(engine) as session:
+        session.add(hero_2)
+        session.commit()
+        session.refresh(hero_2)
+
+    with Session(engine) as session:
+        heroes = session.query(Hero).all()
+        assert len(heroes) == 2
+        assert heroes[0].name == heroes[1].name
+
+
+def test_should_raise_exception_when_try_to_duplicate_row_if_unique_constraint_is_true(
+    clear_sqlmodel,
+):
+    class Hero(SQLModel, table=True):
+        id: Optional[int] = Field(default=None, primary_key=True)
+        name: str
+        secret_name: str = Field(unique=True)
+        age: Optional[int] = None
+
+    hero_1 = Hero(name="Deadpond", secret_name="Dive Wilson")
+    hero_2 = Hero(name="Deadpond", secret_name="Dive Wilson")
+
+    engine = create_engine("sqlite://")
+
+    SQLModel.metadata.create_all(engine)
+
+    with Session(engine) as session:
+        session.add(hero_1)
+        session.commit()
+        session.refresh(hero_1)
+
+    with pytest.raises(IntegrityError):
+        with Session(engine) as session:
+            session.add(hero_2)
+            session.commit()
+            session.refresh(hero_2)