Align Python fallback client with Rust CLI (#911)

python/CHANGELOG.md

@@ -9,6 +9,10 @@ Note that for version number starting with a `0`, i.e., `0.x.y`, a bump of `x`
 should be considered as a major (and thus potentially breaking) change. See
 semver guidelines for more details about this.
 
+## [Unreleased]
+- Python fallback client: removed `--compatibility-mode` / `-c` flag. Its original purpose (output mimicking Unix `file`) was lost when the `magic` field was removed in v0.6.1; it had since been a no-op alias for `--no-colors`.
+- Python fallback client: colors are now auto-disabled when stdout is not a TTY, matching Rust client behavior. Use `--colors` to force them on, `--no-colors` to force them off.
+
 ## [1.0.2] - 2026-02-25
 - Mark python 3.14 as supported.
 - Remove direct dependency on numpy.

python/src/magika/cli/magika_client.py

@@ -83,13 +83,6 @@
     is_flag=True,
     help="Output a simple label instead of a verbose content type description. Use --list-output-content-types for the list of supported output.",
 )
-@click.option(
-    "-c",
-    "--compatibility-mode",
-    "magic_compatibility_mode",
-    is_flag=True,
-    help="Compatibility mode: output is as close as possible to `file` and colors are disabled.",
-)
 @click.option(
     "-s",
     "--output-score",
@@ -112,11 +105,18 @@
     help="This option causes symlinks not to be followed. By default, symlinks are dereferenced.",
 )
 @click.option(
-    "--colors/--no-colors",
-    "with_colors",
+    "--colors",
+    "force_colors",
+    is_flag=True,
+    default=False,
+    help="Force color output regardless of terminal support.",
+)
+@click.option(
+    "--no-colors",
+    "no_colors",
     is_flag=True,
-    default=True,
-    help="Enable/disable use of colors.",
+    default=False,
+    help="Disable color output regardless of terminal support.",
 )
 @click.option("-v", "--verbose", is_flag=True, help="Enable more verbose output.")
 @click.option("-vv", "--debug", is_flag=True, help="Enable debug logging.")
@@ -137,12 +137,12 @@ def main(
     jsonl_output: bool,
     mime_output: bool,
     label_output: bool,
-    magic_compatibility_mode: bool,
     output_score: bool,
     prediction_mode_str: str,
     batch_size: int,
     no_dereference: bool,
-    with_colors: bool,
+    force_colors: bool,
+    no_colors: bool,
     verbose: bool,
     debug: bool,
     output_version: bool,
@@ -154,9 +154,16 @@ def main(
     # the argument "file" (which is ugly) and we re-assign it as soon as we can.
     files_paths = file
 
-    if magic_compatibility_mode:
-        # In compatibility mode we disable colors.
+    if force_colors and no_colors:
+        click.echo("Error: --colors and --no-colors are mutually exclusive.", err=True)
+        sys.exit(1)
+
+    if force_colors:
+        with_colors = True
+    elif no_colors:
         with_colors = False
+    else:
+        with_colors = sys.stdout.isatty()
 
     _l = get_logger(use_colors=with_colors)
 
@@ -198,8 +205,8 @@ def main(
         _l.error("You should use either --json or --jsonl, not both.")
         sys.exit(1)
 
-    if int(mime_output) + int(label_output) + int(magic_compatibility_mode) > 1:
-        _l.error("You should use only one of --mime, --label, --compatibility-mode.")
+    if int(mime_output) + int(label_output) > 1:
+        _l.error("You should use only one of --mime-type, --label.")
         sys.exit(1)
 
     if recursive:
@@ -283,8 +290,6 @@ def main(
             for file_path, result in zip(batch_files_paths, batch_predictions):
                 if result.ok:
                     if mime_output:
-                        # If the user requested the MIME type, we use the mime type
-                        # regardless of the compatibility mode.
                         output = result.prediction.output.mime_type
                     elif label_output:
                         output = str(result.prediction.output.label)

python/tests/test_python_magika_client.py

@@ -13,19 +13,39 @@
 # limitations under the License.
 
 import subprocess
+import sys
 from pathlib import Path
 
+CLIENT = (
+    Path(__file__).parent.parent / "src" / "magika" / "cli" / "magika_client.py"
+).resolve()
+
+
+def _run(*args: str) -> subprocess.CompletedProcess:
+    return subprocess.run(
+        [sys.executable, str(CLIENT), *args], capture_output=True, text=True
+    )
 
-def test_python_magika_client() -> None:
-    python_root_dir = Path(__file__).parent.parent
-    python_magika_client_path = (
-        python_root_dir / "src" / "magika" / "cli" / "magika_client.py"
-    ).resolve()
 
+def test_python_magika_client() -> None:
     # quick test to check there are no obvious problems
-    cmd = [str(python_magika_client_path), "--help"]
-    subprocess.run(cmd, capture_output=True, check=True)
+    subprocess.run([sys.executable, str(CLIENT), "--help"], capture_output=True, check=True)
 
     # quick test to check there are no crashes
-    cmd = [str(python_magika_client_path), str(python_magika_client_path)]
-    subprocess.run(cmd, capture_output=True, check=True)
+    subprocess.run([sys.executable, str(CLIENT), str(CLIENT)], capture_output=True, check=True)
+
+
+def test_compatibility_mode_removed() -> None:
+    result = _run("--compatibility-mode", str(CLIENT))
+    assert result.returncode != 0, "--compatibility-mode should no longer be accepted"
+
+
+def test_no_colors_flag() -> None:
+    result = _run("--no-colors", str(CLIENT))
+    assert result.returncode == 0
+    assert "\x1b[" not in result.stdout, "--no-colors should produce no ANSI escape codes"
+
+
+def test_colors_flag() -> None:
+    result = _run("--colors", str(CLIENT))
+    assert result.returncode == 0