add: do not create empty [tool.poetry.group] sections when adding a dependency to [dependency-groups] (#10130)

Author: radoering

src/poetry/console/commands/add.py

@@ -198,21 +198,11 @@ def handle(self) -> int:
                     for dep in groups_content[group]
                 ]
 
-            if "group" not in poetry_content:
-                poetry_content["group"] = table(is_super_table=True)
-
-            groups = poetry_content["group"]
-
-            if group not in groups:
-                groups[group] = table()
-                groups.add(nl())
-
-            this_group = groups[group]
-
-            if "dependencies" not in this_group:
-                this_group["dependencies"] = table()
-
-            poetry_section = this_group["dependencies"]
+            poetry_section = (
+                poetry_content.get("group", {})
+                .get(group, {})
+                .get("dependencies", table())
+            )
             project_section = []
 
         existing_packages = self.get_existing_packages_from_input(
@@ -379,8 +369,21 @@ def handle(self) -> int:
                 content["tool"] = table()
             if "poetry" not in content["tool"]:
                 content["tool"]["poetry"] = poetry_content
-            if group == MAIN_GROUP and "dependencies" not in poetry_content:
-                poetry_content["dependencies"] = poetry_section
+            if group == MAIN_GROUP:
+                if "dependencies" not in poetry_content:
+                    poetry_content["dependencies"] = poetry_section
+            else:
+                if "group" not in poetry_content:
+                    poetry_content["group"] = table(is_super_table=True)
+
+                groups = poetry_content["group"]
+
+                if group not in groups:
+                    groups[group] = table()
+                    groups.add(nl())
+
+                if "dependencies" not in groups[group]:
+                    groups[group]["dependencies"] = poetry_section
 
         if groups_content and group != MAIN_GROUP:
             if "dependency-groups" not in content:

tests/console/commands/test_add.py

@@ -633,8 +633,9 @@ def test_add_to_new_group_keeps_existing_group(
     ]
 
 
+@pytest.mark.parametrize("additional_poetry_group", [False, True])
 def test_add_to_existing_group(
-    app: PoetryTestApplication, tester: CommandTester
+    app: PoetryTestApplication, tester: CommandTester, additional_poetry_group: bool
 ) -> None:
     pyproject: dict[str, Any] = app.poetry.file.read()
     groups_content: dict[str, Any] = tomlkit.parse(
@@ -646,6 +647,16 @@ def test_add_to_existing_group(
 """
     )
     pyproject["dependency-groups"] = groups_content["dependency-groups"]
+    if additional_poetry_group:
+        poetry_groups_content: dict[str, Any] = tomlkit.parse(
+            """\
+[tool.poetry.group.example.dependencies]
+cachy = { allow-prereleases = true }
+"""
+        )
+        pyproject["tool"]["poetry"]["group"] = poetry_groups_content["tool"]["poetry"][
+            "group"
+        ]
     pyproject = cast("TOMLDocument", pyproject)
     app.poetry.file.write(pyproject)
 
@@ -666,6 +677,13 @@ def test_add_to_existing_group(
         "cachy (>=0.2.0,<0.3.0)",
         "pendulum (>=1.4.4,<2.0.0)",
     ]
+    if additional_poetry_group:
+        assert "example" in pyproject["tool"]["poetry"]["group"]
+        assert pyproject["tool"]["poetry"]["group"]["example"]["dependencies"] == {
+            "cachy": {"allow-prereleases": True},
+        }
+    else:
+        assert "group" not in pyproject["tool"]["poetry"]
 
 
 def test_add_to_group_with_latest_overwrite_existing(
@@ -757,6 +775,7 @@ def test_add_to_group_uses_existing_legacy_group(
 
     pyproject = app.poetry.file.read()
     pyproject = cast("dict[str, Any]", pyproject)
+    assert "dependency-groups" not in pyproject
     assert "example" in pyproject["tool"]["poetry"]["group"]
     assert "pendulum" in pyproject["tool"]["poetry"]["group"]["example"]["dependencies"]
     assert "cachy" in pyproject["tool"]["poetry"]["group"]["example"]["dependencies"]