Generate gitignore files

Author: Miskler

README.md

@@ -79,6 +79,7 @@ The generator writes:
 - `requirements.txt`
 - `requirements-dev.txt`
 - `Makefile`
+- `.gitignore`
 - `.github/workflows/source-sync.yml`
 - `.github/workflows/tests.yml`
 - `.github/workflows/publish.yml`

msra_codegen/config.toml

@@ -23,6 +23,35 @@ base = [
     "mypy",
 ]
 
+[gitignore]
+patterns = [
+    "# Python bytecode",
+    "__pycache__/",
+    "*.py[cod]",
+    "*.pyd",
+    "# Virtual environments",
+    ".venv/",
+    "venv/",
+    "env/",
+    "# Test, lint, and coverage caches",
+    ".pytest_cache/",
+    ".mypy_cache/",
+    ".ruff_cache/",
+    ".coverage",
+    "coverage.xml",
+    "coverage.svg",
+    "htmlcov/",
+    "# Build artifacts",
+    "build/",
+    "dist/",
+    "*.egg-info/",
+    "# Generated project noise",
+    "merged.msra",
+    "error.log",
+    "screenshot.png",
+    "docs/_build/",
+]
+
 [classifiers]
 static = [
     "Operating System :: Microsoft :: Windows",

msra_codegen/gitignore.py

@@ -0,0 +1,31 @@
+from __future__ import annotations
+
+from pathlib import Path
+from typing import Any
+
+from .file_utils import write_text
+from .generator_config import config_section
+from .template_engine import render_template
+
+
+def build_gitignore_context() -> dict[str, Any]:
+    gitignore_config = config_section("gitignore")
+    patterns = gitignore_config.get("patterns")
+    if not isinstance(patterns, list) or not patterns:
+        raise RuntimeError("gitignore.patterns must be a non-empty list.")
+
+    normalized_patterns: list[str] = []
+    for index, pattern in enumerate(patterns):
+        if not isinstance(pattern, str):
+            raise TypeError(f"gitignore.patterns[{index}] must be a string.")
+        normalized_patterns.append(pattern.rstrip())
+
+    return {"patterns": normalized_patterns}
+
+
+def generate_gitignore_project(output_dir: Path) -> None:
+    context = build_gitignore_context()
+    write_text(
+        output_dir / ".gitignore",
+        render_template("gitignore.tpl", context),
+    )

msra_codegen/package_writer.py

@@ -15,6 +15,7 @@
     render_manager_template,
     write_group_package,
 )
+from .gitignore import generate_gitignore_project
 from .github_workflows import generate_github_workflows_project
 from .issue_templates import generate_github_issue_templates_project
 from .core_naming import abstraction_module_name_from_path, normalize_abstraction_path, normalize_script_path
@@ -151,6 +152,7 @@ def generate_project(
     if legacy_license_dir.exists():
         shutil.rmtree(legacy_license_dir)
     write_root_license(output_dir, project)
+    generate_gitignore_project(output_dir)
     generate_github_workflows_project(project, output_dir, package_name)
     generate_github_issue_templates_project(project, output_dir)
 

msra_codegen/templates/gitignore.tpl

@@ -0,0 +1,3 @@
+{% for pattern in patterns -%}
+{{ pattern }}
+{% endfor %}

tests/codegen.test.js

@@ -772,12 +772,18 @@ test("python codegen generates both bundled msra documents without failing", ()
       );
       const normalizedSourceSyncWorkflowText = normalizeNewlines(sourceSyncWorkflowText);
       const normalizedPublishWorkflowText = normalizeNewlines(publishWorkflowText);
+      const gitignoreText = readFileSync(path.join(testCase.outputDir, ".gitignore"), "utf8");
       assert.match(makefileText, /pip install -r requirements-dev\.txt/);
       assert.match(makefileText, new RegExp(`pytest --cov=${testCase.packageName}`));
       assert.match(makefileText, new RegExp(`python -m ruff check ${testCase.packageName} tests example\\.py docs/source/conf\\.py`));
       assert.match(makefileText, new RegExp(`python -m ruff check --select I --fix ${testCase.packageName} tests example\\.py docs/source/conf\\.py`));
       assert.match(makefileText, new RegExp(`python -m ruff format ${testCase.packageName} tests example\\.py docs/source/conf\\.py`));
       assert.match(makefileText, new RegExp(`python -m mypy ${testCase.packageName}`));
+      assert.match(gitignoreText, /^# Python bytecode$/m);
+      assert.match(gitignoreText, /^__pycache__\/$/m);
+      assert.match(gitignoreText, /^\.pytest_cache\/$/m);
+      assert.match(gitignoreText, /^merged\.msra$/m);
+      assert.match(gitignoreText, /^docs\/_build\/$/m);
       assert.match(normalizedSourceSyncWorkflowText, /name: source-sync/);
       assert.match(normalizedSourceSyncWorkflowText, /workflow_dispatch:/);
       assert.match(normalizedSourceSyncWorkflowText, /uses: actions\/checkout@v4/);