Code Flag Options

AUTHORS.md

@@ -68,6 +68,7 @@ Multiple contributions by:
 - Gustavo Camargo
 - hauntsaninja
 - [Hadi Alqattan](mailto:alqattanhadizaki@gmail.com)
+- [Hassan Abouelela](mailto:hassan@hassanamr.com)
 - [Heaford](mailto:dan@heaford.com)
 - [Hugo Barrera](mailto::hugo@barrera.io)
 - Hugo van Kemenade

CHANGES.md

@@ -9,6 +9,7 @@
 - Respect `.gitignore` files in all levels, not only `root/.gitignore` file (apply
   `.gitignore` rules like `git` does) (#2225)
 - Restored compatibility with Click 8.0 on Python 3.6 when LANG=C used (#2227)
+- Fixed option usage when using the `--code` flag (#2259)
 - Add extra uvloop install + import support if in python env (#2258)
 
 ### _Blackd_

docs/usage_and_configuration/the_basics.md

@@ -68,13 +68,6 @@ $ black --code "print ( 'hello, world' )"
 print("hello, world")
 ```
 
-```{warning}
---check, --diff, and --safe / --fast have no effect when using -c / --code. Safety
-checks normally turned on by default that verify _Black_'s output are disabled as well.
-This is a bug which we intend to fix eventually. More details can be found in this [bug
-report](https://github.com/psf/black/issues/2104).
-```
-
 ### Writeback and reporting
 
 By default _Black_ reformats the files given and/or found in place. Sometimes you need

src/black/__init__.py

@@ -29,6 +29,7 @@
 from dataclasses import replace
 import click
 
+from black import output
 from black.const import DEFAULT_LINE_LENGTH, DEFAULT_INCLUDES, DEFAULT_EXCLUDES
 from black.const import STDIN_PLACEHOLDER
 from black.nodes import STARS, syms, is_simple_decorator_expression
@@ -385,8 +386,29 @@ def main(
     if config and verbose:
         out(f"Using configuration from {config}.", bold=False, fg="blue")
     if code is not None:
-        print(format_str(code, mode=mode))
+        then = datetime.utcnow()
+
+        try:
+            formatted = format_file_contents(code, fast=fast, mode=mode)
+        except NothingChanged:
+            formatted = code
+
+        if write_back is WriteBack.CHECK:
+            ctx.exit(0 if code == formatted else 1)
+        elif write_back in (WriteBack.DIFF, WriteBack.COLOR_DIFF):
+            now = datetime.utcnow()
+            src_name = f"STDIN\t{then} +0000"
+            dst_name = f"STDOUT\t{now} +0000"
+
+            diff_contents = output.diff(code, formatted, src_name, dst_name)
+            if write_back == WriteBack.COLOR_DIFF:
+                diff_contents = color_diff(diff_contents)
+            print(diff_contents)
+        else:
+            print(formatted)
+
         ctx.exit(0)
+
     report = Report(check=check, diff=diff, quiet=quiet, verbose=verbose)
     sources = get_sources(
         ctx=ctx,

tests/test_black.py

@@ -34,6 +34,7 @@
 from black import Feature, TargetVersion
 from black.cache import get_cache_file
 from black.debug import DebugVisitor
+from black.output import diff, color_diff
 from black.report import Report
 import black.files
 
@@ -63,6 +64,9 @@
 T = TypeVar("T")
 R = TypeVar("R")
 
+# Match the time output in a diff, but nothing else
+DIFF_TIME = re.compile(r"\t[\d-:+\. ]+")
+
 
 @contextmanager
 def cache_dir(exists: bool = True) -> Iterator[Path]:
@@ -2069,6 +2073,102 @@ def test_docstring_reformat_for_py27(self) -> None:
         actual = result.output
         self.assertFormatEqual(actual, expected)
 
+    def test_code_option(self) -> None:
+        """Test the code option with no changes."""
+        code = 'print("Hello world")\n'
+        args = ["--code", code]
+        result = CliRunner().invoke(black.main, args)
+
+        # The CLI prints an extra linebreak when exiting.
+        self.assertEqual(result.output, code + "\n")
+        self.assertEqual(result.exit_code, 0)
+
+    def test_code_option_changed(self) -> None:
+        """Test the code option when changes are required."""
+        code = "print('hello world')"
+        # The CLI prints an extra linebreak when exiting.
+        formatted = black.format_str(code, mode=DEFAULT_MODE) + "\n"
+
+        args = ["--code", code]
+        result = CliRunner().invoke(black.main, args)
+
+        self.assertEqual(result.output, formatted)
+        self.assertEqual(result.exit_code, 0)
+
+    def test_code_option_check(self) -> None:
+        """Test the code option when check is passed."""
+        args = ["--check", "--code", 'print("Hello world")\n']
+        result = CliRunner().invoke(black.main, args)
+
+        self.assertEqual(result.output, "")
+        self.assertEqual(result.exit_code, 0)
+
+    def test_code_option_check_changed(self) -> None:
+        """Test the code option when changes are required, and check is passed."""
+        args = ["--check", "--code", "print('hello world')"]
+        result = CliRunner().invoke(black.main, args)
+
+        self.assertEqual(result.output, "")
+        self.assertEqual(result.exit_code, 1)
+
+    def test_code_option_diff(self) -> None:
+        """Test the code option when diff is passed."""
+        code = "print('hello world')"
+        formatted = black.format_str(code, mode=DEFAULT_MODE)
+
+        # The CLI prints an extraline break when exiting.
+        result_diff = diff(code, formatted, "STDIN", "STDOUT") + "\n"
+
+        args = ["--diff", "--code", code]
+        result = CliRunner().invoke(black.main, args)
+
+        # Remove time from diff
+        output = DIFF_TIME.sub("", result.output)
+
+        self.assertEqual(output, result_diff)
+        self.assertEqual(result.exit_code, 0)
+
+    def test_code_option_color_diff(self) -> None:
+        """Test the code option when color and diff are passed."""
+        code = "print('hello world')"
+        formatted = black.format_str(code, mode=DEFAULT_MODE)
+
+        result_diff = diff(code, formatted, "STDIN", "STDOUT")
+        # The CLI prints an extraline break when exiting.
+        result_diff = color_diff(result_diff) + "\n"
+
+        args = ["--diff", "--color", "--code", code]
+        result = CliRunner().invoke(black.main, args)
+
+        # Remove time from diff
+        output = DIFF_TIME.sub("", result.output)
+
+        self.assertEqual(output, result_diff)
+        self.assertEqual(result.exit_code, 0)
+
+    def test_code_option_safe(self) -> None:
+        """Test that the code option throws an error when the sanity checks fail."""
+        # Patch black.assert_equivalent to ensure the sanity checks fail
+        with patch.object(black, "assert_equivalent", side_effect=AssertionError):
+            args = ["--safe", "--code", 'print("Hello world")']
+            result = CliRunner().invoke(black.main, args)
+
+            self.assertEqual(result.output, "")
+            self.assertEqual(result.exit_code, 1)
+
+    def test_code_option_fast(self) -> None:
+        """Test that the code option ignores errors when the sanity checks fail."""
+        # Patch black.assert_equivalent to ensure the sanity checks fail
+        with patch.object(black, "assert_equivalent", side_effect=AssertionError):
+            code = 'print("Hello world")'
+            formatted = black.format_str(code, mode=DEFAULT_MODE) + "\n"
+
+            args = ["--fast", "--code", code]
+            result = CliRunner().invoke(black.main, args)
+
+            self.assertEqual(result.output, formatted)
+            self.assertEqual(result.exit_code, 0)
+
 
 with open(black.__file__, "r", encoding="utf-8") as _bf:
     black_source_lines = _bf.readlines()