Implement --remove flag. (#36)

* Implement --remove flag.

* Consistency in whether to include quotes in pre-commit conifg YAML rev

* Use example email in github actions

* Consistency in use of double quotes in YAML

* Fix test in case of empty pre-commit repo list

.github/workflows/ci.yml

@@ -15,8 +15,8 @@ jobs:
 
       - name: Setup git user config
         run: |
-          git config --global user.name github-actions[bot]
-          git config --global user.email 41898282+github-actions[bot]@users.noreply.github.com
+          git config --global user.name placeholder
+          git config --global user.email placeholder@example.com
 
       - name: "Set up uv"
         uses: astral-sh/setup-uv@f3bcaebff5eace81a1c062af9f9011aae482ca9d # v3.1.7

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
   - repo: https://github.com/abravalheri/validate-pyproject
-    rev: v0.21
+    rev: "v0.21"
     hooks:
       - id: validate-pyproject
         additional_dependencies: ["validate-pyproject-schema-store[all]"]

pyproject.toml

@@ -28,16 +28,17 @@ dev-dependencies = [
     "pytest-md>=0.2.0",
     "pytest-emoji>=0.2.0",
     "deptry>=0.20.0",
-    "pre-commit>=4.0.1",
     "ruff>=0.7.0",
     "pytest-cov>=5.0.0",
     "gitpython>=3.1.43",
+    "pre-commit>=4.0.1",
 ]
 
 [tool.coverage.run]
 source = ["src"]
 omit = ["*/pytest-of-*/*"]
 
+
 [tool.ruff]
 src = ["src"]
 line-length = 88

src/usethis/_pre_commit/core.py

@@ -28,7 +28,11 @@
 ]
 
 
-def make_pre_commit_config() -> None:
+def ensure_pre_commit_config() -> None:
+    if (Path.cwd() / ".pre-commit-config.yaml").exists():
+        # Early exit; the file already exists
+        return
+
     console.print("✔ Creating .pre-commit-config.yaml file", style="green")
     try:
         pkg_version = get_github_latest_tag("abravalheri", "validate-pyproject")
@@ -40,34 +44,16 @@ def make_pre_commit_config() -> None:
     (Path.cwd() / ".pre-commit-config.yaml").write_text(yaml_contents)
 
 
-def ensure_pre_commit_config() -> None:
+def remove_pre_commit_config() -> None:
     if not (Path.cwd() / ".pre-commit-config.yaml").exists():
-        make_pre_commit_config()
-
-
-def delete_hook(name: str) -> None:
-    path = Path.cwd() / ".pre-commit-config.yaml"
-
-    with path.open(mode="r") as f:
-        content, sequence_ind, offset_ind = load_yaml_guess_indent(f)
-
-    yaml = ruamel.yaml.YAML(typ="rt")
-    yaml.indent(mapping=sequence_ind, sequence=sequence_ind, offset=offset_ind)
-
-    # search across the repos for any hooks with ID equal to name
-    for repo in content["repos"]:
-        for hook in repo["hooks"]:
-            if hook["id"] == name:
-                repo["hooks"].remove(hook)
+        # Early exit; the file already doesn't exist
+        return
 
-        # if repo has no hooks, remove it
-        if not repo["hooks"]:
-            content["repos"].remove(repo)
-
-    yaml.dump(content, path)
+    console.print("✔ Removing .pre-commit-config.yaml file", style="green")
+    (Path.cwd() / ".pre-commit-config.yaml").unlink()
 
 
-def add_single_hook(config: PreCommitRepoConfig) -> None:
+def add_hook(config: PreCommitRepoConfig) -> None:
     path = Path.cwd() / ".pre-commit-config.yaml"
 
     with path.open(mode="r") as f:
@@ -82,10 +68,14 @@ def add_single_hook(config: PreCommitRepoConfig) -> None:
     # Get an ordered list of the hooks already in the file
     existing_hooks = get_hook_names(path.parent)
 
+    if not existing_hooks:
+        raise NotImplementedError
+
     # Get the precendents, i.e. hooks occuring before the new hook
-    hook_idx = _HOOK_ORDER.index(hook_name)
-    if hook_idx == -1:
-        raise ValueError(f"Hook {hook_name} not recognized")
+    try:
+        hook_idx = _HOOK_ORDER.index(hook_name)
+    except ValueError:
+        raise NotImplementedError(f"Hook '{hook_name}' not recognized")
     precedents = _HOOK_ORDER[:hook_idx]
 
     # Find the last of the precedents in the existing hooks
@@ -111,6 +101,28 @@ def add_single_hook(config: PreCommitRepoConfig) -> None:
     yaml.dump(content, path)
 
 
+def remove_hook(name: str) -> None:
+    path = Path.cwd() / ".pre-commit-config.yaml"
+
+    with path.open(mode="r") as f:
+        content, sequence_ind, offset_ind = load_yaml_guess_indent(f)
+
+    yaml = ruamel.yaml.YAML(typ="rt")
+    yaml.indent(mapping=sequence_ind, sequence=sequence_ind, offset=offset_ind)
+
+    # search across the repos for any hooks with ID equal to name
+    for repo in content["repos"]:
+        for hook in repo["hooks"]:
+            if hook["id"] == name:
+                repo["hooks"].remove(hook)
+
+        # if repo has no hooks, remove it
+        if not repo["hooks"]:
+            content["repos"].remove(repo)
+
+    yaml.dump(content, path)
+
+
 def get_hook_names(path: Path) -> list[str]:
     yaml = ruamel.yaml.YAML()
     with (path / ".pre-commit-config.yaml").open(mode="r") as f:
@@ -140,3 +152,12 @@ def install_pre_commit() -> None:
         check=True,
         stdout=subprocess.DEVNULL,
     )
+
+
+def uninstall_pre_commit() -> None:
+    console.print("✔ Uninstalling pre-commit hooks", style="green")
+    subprocess.run(
+        ["uv", "run", "pre-commit", "uninstall"],
+        check=True,
+        stdout=subprocess.DEVNULL,
+    )

src/usethis/_tool.py

@@ -9,9 +9,10 @@
 from usethis import console
 from usethis._pre_commit.config import HookConfig, PreCommitRepoConfig
 from usethis._pre_commit.core import (
-    add_single_hook,
+    add_hook,
     ensure_pre_commit_config,
     get_hook_names,
+    remove_hook,
 )
 from usethis._pyproject.config import PyProjectConfig
 from usethis._uv.deps import get_dev_deps
@@ -71,12 +72,31 @@ def add_pre_commit_repo_config(self) -> None:
                     )
                     first_time_adding = False
 
-                add_single_hook(
+                add_hook(
                     PreCommitRepoConfig(
                         repo=repo_config.repo, rev=repo_config.rev, hooks=[hook]
                     )
                 )
 
+    def remove_pre_commit_repo_config(self) -> None:
+        """Remove the tool's pre-commit configuration."""
+        try:
+            repo_config = self.get_pre_commit_repo_config()
+        except NotImplementedError:
+            return
+
+        # Remove the config for this specific tool.
+        first_removal = True
+        for hook in repo_config.hooks:
+            if hook.id in get_hook_names(Path.cwd()):
+                if first_removal:
+                    console.print(
+                        f"✔ Removing {self.name} config from .pre-commit-config.yaml",
+                        style="green",
+                    )
+                    first_removal = False
+                remove_hook(hook.id)
+
     def add_pyproject_config(self) -> None:
         """Add the tool's pyproject.toml configuration."""
 
@@ -98,9 +118,7 @@ def add_pyproject_config(self) -> None:
             # The configuration is already present.
             return
 
-        console.print(
-            f"✔ Adding {self.pypi_name} configuration to pyproject.toml", style="green"
-        )
+        console.print(f"✔ Adding {self.name} config to pyproject.toml", style="green")
 
         # The old configuration should be kept for all ID keys except the final/deepest
         # one which shouldn't exist anyway since we checked as much, above. For example,
@@ -110,13 +128,64 @@ def add_pyproject_config(self) -> None:
 
         (Path.cwd() / "pyproject.toml").write_text(tomlkit.dumps(pyproject))
 
+    def remove_pyproject_config(self) -> None:
+        """Remove the tool's pyproject.toml configuration."""
+        try:
+            config = self.get_pyproject_config()
+        except NotImplementedError:
+            return
+
+        pyproject = tomlkit.parse((Path.cwd() / "pyproject.toml").read_text())
+
+        # Exit early if the configuration is not present.
+        try:
+            p = pyproject
+            for key in config.id_keys:
+                p = p[key]
+        except KeyError:
+            # The configuration is not present.
+            return
+
+        console.print(
+            f"✔ Removing {self.name} config from pyproject.toml",
+            style="green",
+        )
+
+        # Remove the configuration.
+        p = pyproject
+        for key in config.id_keys[:-1]:
+            p = p[key]
+        del p[config.id_keys[-1]]
+
+        # Cleanup: any empty sections should be removed.
+        for idx in range(len(config.id_keys) - 1):
+            p = pyproject
+            for key in config.id_keys[: idx + 1]:
+                p = p[key]
+            if not p:
+                del p
+
+        (Path.cwd() / "pyproject.toml").write_text(tomlkit.dumps(pyproject))
+
     def ensure_dev_dep(self) -> None:
         """Add the tool as a development dependency, if it is not already."""
         console.print(
             f"✔ Ensuring {self.pypi_name} is a development dependency", style="green"
         )
         subprocess.run(["uv", "add", "--dev", "--quiet", self.pypi_name], check=True)
 
+    def remove_dev_dep(self) -> None:
+        """Remove the tool as a development dependency, if it is present."""
+        if self.pypi_name not in get_dev_deps(Path.cwd()):
+            # Early exit; the tool is already not a dev dependency.
+            return
+
+        console.print(
+            f"✔ Removing {self.pypi_name} as a development dependency",
+            style="green",
+        )
+        subprocess.run(["uv", "remove", "--dev", "--quiet", self.pypi_name], check=True)
+
 
 class PreCommitTool(Tool):
     @property

src/usethis/tool.py

@@ -1,6 +1,11 @@
 import typer
 
-from usethis._pre_commit.core import ensure_pre_commit_config, install_pre_commit
+from usethis._pre_commit.core import (
+    ensure_pre_commit_config,
+    install_pre_commit,
+    remove_pre_commit_config,
+    uninstall_pre_commit,
+)
 from usethis._tool import ALL_TOOLS, DeptryTool, PreCommitTool, RuffTool
 
 app = typer.Typer(help="Add and configure development tools, e.g. linters")
@@ -9,30 +14,73 @@
 @app.command(
     help="Use the pre-commit framework to manage and maintain pre-commit hooks."
 )
-def pre_commit() -> None:
+def pre_commit(
+    remove: bool = typer.Option(
+        False, "--remove", help="Remove pre-commit instead of adding it."
+    ),
+) -> None:
+    _pre_commit(remove=remove)
+
+
+def _pre_commit(*, remove: bool = False) -> None:
     tool = PreCommitTool()
-    tool.ensure_dev_dep()
-    ensure_pre_commit_config()
-    for tool in ALL_TOOLS:
-        if tool.is_used():
-            tool.add_pre_commit_repo_config()
-    install_pre_commit()
+
+    if not remove:
+        tool.ensure_dev_dep()
+        ensure_pre_commit_config()
+        for tool in ALL_TOOLS:
+            if tool.is_used():
+                tool.add_pre_commit_repo_config()
+        install_pre_commit()
+    else:
+        uninstall_pre_commit()
+        remove_pre_commit_config()
+        tool.remove_dev_dep()
 
 
 @app.command(
     help="Use the deptry linter: avoid missing or superfluous dependency declarations."
 )
-def deptry() -> None:
+def deptry(
+    remove: bool = typer.Option(
+        False, "--remove", help="Remove deptry instead of adding it."
+    ),
+) -> None:
+    _deptry(remove=remove)
+
+
+def _deptry(*, remove: bool = False) -> None:
     tool = DeptryTool()
-    tool.ensure_dev_dep()
-    if PreCommitTool().is_used():
-        tool.add_pre_commit_repo_config()
+
+    if not remove:
+        tool.ensure_dev_dep()
+        if PreCommitTool().is_used():
+            tool.add_pre_commit_repo_config()
+    else:
+        if PreCommitTool().is_used():
+            tool.remove_pre_commit_repo_config()
+        tool.remove_dev_dep()
 
 
 @app.command(help="Use ruff: an extremely fast Python linter and code formatter.")
-def ruff() -> None:
+def ruff(
+    remove: bool = typer.Option(
+        False, "--remove", help="Remove ruff instead of adding it."
+    ),
+) -> None:
+    _ruff(remove=remove)
+
+
+def _ruff(*, remove: bool = False) -> None:
     tool = RuffTool()
-    tool.ensure_dev_dep()
-    tool.add_pyproject_config()
-    if PreCommitTool().is_used():
-        tool.add_pre_commit_repo_config()
+
+    if not remove:
+        tool.ensure_dev_dep()
+        tool.add_pyproject_config()
+        if PreCommitTool().is_used():
+            tool.add_pre_commit_repo_config()
+    else:
+        if PreCommitTool().is_used():
+            tool.remove_pre_commit_repo_config()
+        tool.remove_pyproject_config()
+        tool.remove_dev_dep()

tests/conftest.py

@@ -0,0 +1,18 @@
+import subprocess
+from pathlib import Path
+
+import pytest
+from git import Repo
+
+
+@pytest.fixture(scope="function")
+def uv_init_dir(tmp_path: Path) -> Path:
+    subprocess.run(["uv", "init", "--lib"], cwd=tmp_path, check=True)
+    return tmp_path
+
+
+@pytest.fixture(scope="function")
+def uv_init_repo_dir(tmp_path: Path) -> Path:
+    subprocess.run(["uv", "init", "--lib"], cwd=tmp_path, check=True)
+    Repo.init(tmp_path)
+    return tmp_path