✅ Use Ruff rules to ensure safe lazy-loading of rich (#1297)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Sofie Van Landeghem <svlandeg@users.noreply.github.com>

Author: 3 people

pyproject.toml

@@ -164,16 +164,20 @@ select = [
     "B",  # flake8-bugbear
     "C4",  # flake8-comprehensions
     "UP", # pyupgrade
+    "TID", # flake8-tidy-imports
 ]
 ignore = [
     "E501",  # line too long, handled by black
     "B008",  # do not perform function calls in argument defaults
     "C901",  # too complex
     "W191", # indentation contains tabs
+    "TID252", # relative imports okay
 ]
 
 [tool.ruff.lint.per-file-ignores]
 # "__init__.py" = ["F401"]
+# rich_utils is allowed to use rich imports
+"typer/rich_utils.py" = ["TID251"]
 # This file is more readable without yield from
 "docs_src/progressbar/tutorial004.py" = ["UP028", "B007"]
 # Default mutable data structure
@@ -192,6 +196,8 @@ ignore = [
 "docs_src/prompt/tutorial003.py" = ["F841"]
 # Loop control variable `x` not used within loop body
 "docs_src/using_click/tutorial001.py" = ["B007"]
+# No need to worry about rich imports in docs
+"docs_src/*" = ["TID"]
 
 [tool.ruff.lint.isort]
 known-third-party = ["typer", "click"]
@@ -201,3 +207,10 @@ known-first-party = ["reigns", "towns", "lands", "items", "users"]
 [tool.ruff.lint.pyupgrade]
 # Preserve types, even if a file imports `from __future__ import annotations`.
 keep-runtime-typing = true
+
+[tool.ruff.lint.flake8-tidy-imports]
+# Import rich_utils from within functions (lazy), not at the module level (TID253)
+banned-module-level-imports = ["typer.rich_utils"]
+
+[tool.ruff.lint.flake8-tidy-imports.banned-api]
+"rich".msg = "Use 'typer.rich_utils' instead of importing from 'rich' directly."

tests/assets/type_error_no_rich.py

@@ -1,7 +1,7 @@
 import typer
 import typer.main
 
-typer.main.rich = None
+typer.main.HAS_RICH = False
 
 
 def main(name: str = "morty"):

tests/assets/type_error_no_rich_short_disable.py

@@ -1,7 +1,7 @@
 import typer
 import typer.main
 
-typer.main.rich = None
+typer.main.HAS_RICH = False
 
 
 app = typer.Typer(pretty_exceptions_short=False)

tests/test_corner_cases.py

@@ -1,3 +1,4 @@
+import pytest
 import typer.core
 from typer.testing import CliRunner
 
@@ -16,17 +17,16 @@ def test_hidden_option():
     assert "(dynamic)" in result.output
 
 
-def test_hidden_option_no_rich():
-    rich = typer.core.rich
-    typer.core.rich = None
+def test_hidden_option_no_rich(monkeypatch: pytest.MonkeyPatch):
+    monkeypatch.setattr(typer.core, "HAS_RICH", False)
+
     result = runner.invoke(mod.app, ["--help"])
     assert result.exit_code == 0
     assert "Say hello" in result.output
     assert "--name" not in result.output
     assert "/lastname" in result.output
     assert "TEST_LASTNAME" in result.output
     assert "(dynamic)" in result.output
-    typer.core.rich = rich
 
 
 def test_coverage_call():

tests/test_tutorial/test_arguments/test_envvar/test_tutorial001.py

@@ -1,6 +1,7 @@
 import subprocess
 import sys
 
+import pytest
 import typer
 import typer.core
 from typer.testing import CliRunner
@@ -22,16 +23,14 @@ def test_help():
     assert "default: World" in result.output
 
 
-def test_help_no_rich():
-    rich = typer.core.rich
-    typer.core.rich = None
+def test_help_no_rich(monkeypatch: pytest.MonkeyPatch):
+    monkeypatch.setattr(typer.core, "HAS_RICH", False)
     result = runner.invoke(app, ["--help"])
     assert result.exit_code == 0
     assert "[OPTIONS] [NAME]" in result.output
     assert "Arguments" in result.output
     assert "env var: AWESOME_NAME" in result.output
     assert "default: World" in result.output
-    typer.core.rich = rich
 
 
 def test_call_arg():

tests/test_tutorial/test_arguments/test_envvar/test_tutorial001_an.py

@@ -1,6 +1,7 @@
 import subprocess
 import sys
 
+import pytest
 import typer
 import typer.core
 from typer.testing import CliRunner
@@ -22,16 +23,15 @@ def test_help():
     assert "default: World" in result.output
 
 
-def test_help_no_rich():
-    rich = typer.core.rich
-    typer.core.rich = None
+def test_help_no_rich(monkeypatch: pytest.MonkeyPatch):
+    monkeypatch.setattr(typer.core, "HAS_RICH", False)
+
     result = runner.invoke(app, ["--help"])
     assert result.exit_code == 0
     assert "[OPTIONS] [NAME]" in result.output
     assert "Arguments" in result.output
     assert "env var: AWESOME_NAME" in result.output
     assert "default: World" in result.output
-    typer.core.rich = rich
 
 
 def test_call_arg():

tests/test_tutorial/test_arguments/test_help/test_tutorial001.py

@@ -1,6 +1,7 @@
 import subprocess
 import sys
 
+import pytest
 import typer
 import typer.core
 from typer.testing import CliRunner
@@ -23,17 +24,15 @@ def test_help():
     assert "[required]" in result.output
 
 
-def test_help_no_rich():
-    rich = typer.core.rich
-    typer.core.rich = None
+def test_help_no_rich(monkeypatch: pytest.MonkeyPatch):
+    monkeypatch.setattr(typer.core, "HAS_RICH", False)
     result = runner.invoke(app, ["--help"])
     assert result.exit_code == 0
     assert "[OPTIONS] NAME" in result.output
     assert "Arguments" in result.output
     assert "NAME" in result.output
     assert "The name of the user to greet" in result.output
     assert "[required]" in result.output
-    typer.core.rich = rich
 
 
 def test_call_arg():

tests/test_tutorial/test_arguments/test_help/test_tutorial001_an.py

@@ -1,6 +1,7 @@
 import subprocess
 import sys
 
+import pytest
 import typer
 import typer.core
 from typer.testing import CliRunner
@@ -23,17 +24,15 @@ def test_help():
     assert "[required]" in result.output
 
 
-def test_help_no_rich():
-    rich = typer.core.rich
-    typer.core.rich = None
+def test_help_no_rich(monkeypatch: pytest.MonkeyPatch):
+    monkeypatch.setattr(typer.core, "HAS_RICH", False)
     result = runner.invoke(app, ["--help"])
     assert result.exit_code == 0
     assert "[OPTIONS] NAME" in result.output
     assert "Arguments" in result.output
     assert "NAME" in result.output
     assert "The name of the user to greet" in result.output
     assert "[required]" in result.output
-    typer.core.rich = rich
 
 
 def test_call_arg():

tests/test_tutorial/test_arguments/test_help/test_tutorial008.py

@@ -1,6 +1,7 @@
 import subprocess
 import sys
 
+import pytest
 import typer
 import typer.core
 from typer.testing import CliRunner
@@ -22,16 +23,14 @@ def test_help():
     assert "[default: World]" not in result.output
 
 
-def test_help_no_rich():
-    rich = typer.core.rich
-    typer.core.rich = None
+def test_help_no_rich(monkeypatch: pytest.MonkeyPatch):
+    monkeypatch.setattr(typer.core, "HAS_RICH", False)
     result = runner.invoke(app, ["--help"])
     assert result.exit_code == 0
     assert "[OPTIONS] [NAME]" in result.output
     assert "Say hi to NAME very gently, like Dirk." in result.output
     assert "Arguments" not in result.output
     assert "[default: World]" not in result.output
-    typer.core.rich = rich
 
 
 def test_call_arg():

tests/test_tutorial/test_arguments/test_help/test_tutorial008_an.py

@@ -1,6 +1,7 @@
 import subprocess
 import sys
 
+import pytest
 import typer
 import typer.core
 from typer.testing import CliRunner
@@ -22,16 +23,14 @@ def test_help():
     assert "[default: World]" not in result.output
 
 
-def test_help_no_rich():
-    rich = typer.core.rich
-    typer.core.rich = None
+def test_help_no_rich(monkeypatch: pytest.MonkeyPatch):
+    monkeypatch.setattr(typer.core, "HAS_RICH", False)
     result = runner.invoke(app, ["--help"])
     assert result.exit_code == 0
     assert "[OPTIONS] [NAME]" in result.output
     assert "Say hi to NAME very gently, like Dirk." in result.output
     assert "Arguments" not in result.output
     assert "[default: World]" not in result.output
-    typer.core.rich = rich
 
 
 def test_call_arg():