Add tool to generate formatting fixtures

.pre-commit-config.yaml

@@ -50,10 +50,14 @@ repos:
     rev: v4.1.0
     hooks:
       - id: end-of-file-fixer
+        # ignore formatting-prettier to have an accurate prettier comparison
+        # also temporarily ignore formatting-after until #1927 is merged
         exclude: >
           (?x)^(
             test/eco/.*.result|
-            test/fixtures/formatting-before/.*
+            test/fixtures/formatting-before/.*|
+            test/fixtures/formatting-prettier/.*|
+            test/fixtures/formatting-after/.*
           )$
       - id: trailing-whitespace
         exclude: >

pytest.ini

@@ -64,3 +64,4 @@ xfail_strict = true
 
 markers =
     eco: Tests effects on a set of 3rd party ansible repositories
+    formatting_fixtures: Test that regenerates and tests formatting fixtures (requires prettier on PATH)

test/conftest.py

@@ -1,6 +1,15 @@
 import os
 from contextlib import contextmanager
-from typing import Iterator
+from typing import TYPE_CHECKING, Iterator
+
+import pytest
+
+if TYPE_CHECKING:
+    from typing import List  # pylint: disable=ungrouped-imports
+
+    from _pytest import nodes
+    from _pytest.config import Config
+    from _pytest.config.argparsing import Parser
 
 
 @contextmanager
@@ -12,3 +21,31 @@ def cwd(path: str) -> Iterator[None]:
         yield
     finally:
         os.chdir(old_pwd)
+
+
+def pytest_addoption(parser: "Parser") -> None:
+    """Add --regenerate-formatting-fixtures option to pytest."""
+    parser.addoption(
+        "--regenerate-formatting-fixtures",
+        action="store_true",
+        default=False,
+        help="Regenerate formatting fixtures with prettier and internal formatter",
+    )
+
+
+def pytest_collection_modifyitems(items: "List[nodes.Item]", config: "Config") -> None:
+    """Skip tests based on --regenerate-formatting-fixtures option."""
+    do_regenerate = config.getoption("--regenerate-formatting-fixtures")
+    skip_other = pytest.mark.skip(
+        reason="not a formatting_fixture test and "
+        "--regenerate-formatting-fixtures was specified"
+    )
+    skip_formatting_fixture = pytest.mark.skip(
+        reason="specify --regenerate-formatting-fixtures to "
+        "only run formatting_fixtures test"
+    )
+    for item in items:
+        if do_regenerate and "formatting_fixtures" not in item.keywords:
+            item.add_marker(skip_other)
+        elif not do_regenerate and "formatting_fixtures" in item.keywords:
+            item.add_marker(skip_formatting_fixture)

test/fixtures/__init__.py

@@ -0,0 +1 @@
+"""Fixtures used in tests."""

test/fixtures/formatting-after/fmt-1.yml

@@ -44,3 +44,4 @@ overly-indented-vault-value: !vault |
   123466303630313
 
 # this file also has 3 newlines at end-of-file instead of one
+

test/fixtures/formatting-after/fmt-2.yml

@@ -0,0 +1,19 @@
+# preamble/header comment
+---
+# initial comment
+- foo: bar
+
+- baz: # over indented
+    - qwerty
+    - foobar
+  animals: # under indented
+    - crow
+    - pig
+    - giraffe
+
+- nothing: null # null
+
+- octal:
+    - 0o123 # YAML 1.2 octal
+    - 0123 # YAML 1.1 octal
+

test/fixtures/formatting-before/fmt-2.yml

@@ -0,0 +1,19 @@
+# preamble/header comment
+---
+# initial comment
+  - foo: bar
+
+  - baz:  # over indented
+        - qwerty
+        - foobar
+    animals: # under indented
+    - crow
+    - pig
+    - giraffe
+
+  - nothing: null  # null
+
+  - octal:
+    - 0o123  # YAML 1.2 octal
+    - 0123  # YAML 1.1 octal
+

test/fixtures/formatting-prettier/fmt-1.yml

@@ -0,0 +1,47 @@
+---
+# ^ too many newlines before
+foo: bar # This is a comment has extra spaces preceding it
+
+fruits: # unindented sequence:
+  - apple
+  - orange
+vegetables: # indented sequence:
+  - onion
+  - carrot
+
+quoting:
+  - "that should have double quotes"
+  - "that should remain in single quotes"
+  - 'a string with " inside'
+  # next line has some undesired trailing spaces:
+  - "a string with ' inside"
+  - can't be sure!
+  # next line should be converted to use double quotes:
+  - ["foo", "bar"]
+
+inline-dictionary:
+  - { foo: bar } # should add some spacing between curly braces and content
+
+# YAML 1.1 Boolean-hell: https://yaml.org/type/bool.html
+booleans-true:
+  preferred: true # YAML 1.2 compatible!
+  answer-1.1: YES
+  canonical-1.1: y
+  canonical-upper-1.1: Y
+  logical-1.1: True
+  option-1.1: on
+booleans-false:
+  preferred: false # YAML 1.2 compatible!
+  answer-1.1: NO
+  canonical-1.1: n
+  canonical-upper-1.1: N
+  logical-1.1: False
+  option-1.1: off
+
+# ^ double newline should be removed
+overly-indented-vault-value: !vault |
+  $ANSIBLE_VAULT;1.1;AES256
+  123466303630313
+
+# this file also has 3 newlines at end-of-file instead of one
+

test/fixtures/formatting-prettier/fmt-2.yml

@@ -0,0 +1,19 @@
+# preamble/header comment
+---
+# initial comment
+- foo: bar
+
+- baz: # over indented
+    - qwerty
+    - foobar
+  animals: # under indented
+    - crow
+    - pig
+    - giraffe
+
+- nothing: null # null
+
+- octal:
+    - 0o123 # YAML 1.2 octal
+    - 0123 # YAML 1.1 octal
+

test/fixtures/test_regenerate_formatting_fixtures.py

@@ -0,0 +1,39 @@
+"""Test that re-generates formatting fixtures."""
+import shutil
+import subprocess
+from pathlib import Path
+
+import pytest
+
+
+@pytest.mark.formatting_fixtures()
+def test_regenerate_formatting_fixtures() -> None:
+    """Re-generate formatting fixtures with prettier and internal formatter.
+
+    Pass ``--regenerate-formatting-fixtures`` to run this and skip all other tests.
+    This is a "test" because once fixtures are regenerated,
+    we run prettier again to make sure it does not change files formatted
+    with our internal formatting code.
+    """
+    print("Looking for prettier on PATH...")
+    subprocess.check_call(["which", "prettier"])
+
+    fixtures_dir = Path("test/fixtures/")
+    fixtures_dir_before = fixtures_dir / "formatting-before"
+    fixtures_dir_prettier = fixtures_dir / "formatting-prettier"
+    fixtures_dir_after = fixtures_dir / "formatting-after"
+
+    fixtures_dir_prettier.mkdir(exist_ok=True)
+    fixtures_dir_after.mkdir(exist_ok=True)
+
+    print("\nCopying before fixtures...")
+    for fixture in fixtures_dir_before.glob("fmt-[0-9].yml"):
+        shutil.copy(str(fixture), str(fixtures_dir_prettier / fixture.name))
+        shutil.copy(str(fixture), str(fixtures_dir_after / fixture.name))
+
+    print("\nWriting fixtures with prettier...")
+    subprocess.check_call(["prettier", "-w", str(fixtures_dir_prettier)])
+    # NB: pre-commit end-of-file-fixer can also modify files.
+
+    # prepare ruamel.yaml fixtures (diff in next PR will show how it compares).
+    subprocess.check_call(["prettier", "-w", str(fixtures_dir_after)])