Provide --update option as comma separated list

README.rst

@@ -105,7 +105,7 @@ To update one or more dependencies to the latest allowed version, run:
 
 .. code:: console
 
-    pip-df sync --update DEPENDENCY1 --update DEPENDENCY2 ...
+    pip-df sync --update DEPENDENCY1,DEPENDENCY2 ...
 
 If you need to add some dependencies from VCS references (e.g. when a library
 with a patch you need is not available as a release on a package index), add
@@ -138,7 +138,7 @@ How to
    ``setup.py`` and add the git reference in ``requirements.txt.in``)
 -  Remove a dependency (remove it from ``setup.py``)
 -  Update a dependency to the most recent version
-   (``pip-df sync --update   DEPENDENCY1 --update DEPENDENCY2``)
+   (``pip-df sync --update   DEPENDENCY1,DEPENDENCY2``)
 -  Update all dependencies to the latest version
    (``pip-df sync --update-all`` or remove ``requirements.txt`` and run
    ``pip-df sync``)
@@ -199,12 +199,11 @@ pip-df sync
      dependencies.
 
    Options:
-     -u, --update DEPENDENCY         Make sure DEPENDENCY is upgraded (or
-                                     downgraded) to the latest allowed version.
-                                     If DEPENDENCY is not part of your
+     -u, --update DEP1,DEP2,...      Make sure selected dependencies are upgraded
+                                     (or downgraded) to the latest allowed
+                                     version. If DEP is not part of your
                                      application dependencies anymore, this
-                                     option has no effect. This option can be
-                                     repeated.
+                                     option has no effect.
 
      --update-all                    Upgrade (or downgrade) all dependencies of
                                      your application to the latest allowed

news/33.feature

@@ -0,0 +1 @@
+``--update`` is changed to accept a comma-separated list of distribution names.

src/pip_deepfreeze/__main__.py

@@ -1,13 +1,13 @@
 import shutil
 from pathlib import Path
-from typing import List, Optional
+from typing import Optional
 
 import typer
 
 from .detect import supports_editable
 from .sync import sync as sync_operation
 from .tree import tree as tree_operation
-from .utils import increase_verbosity, log_debug, log_error
+from .utils import comma_split, increase_verbosity, log_debug, log_error
 
 app = typer.Typer()
 
@@ -20,16 +20,15 @@ class MainOptions:
 @app.command()
 def sync(
     ctx: typer.Context,
-    to_upgrade: List[str] = typer.Option(
+    to_upgrade: str = typer.Option(
         None,
         "--update",
         "-u",
-        metavar="DEPENDENCY",
+        metavar="DEP1,DEP2,...",
         help=(
-            "Make sure DEPENDENCY is upgraded (or downgraded) to the latest "
-            "allowed version. If DEPENDENCY is not part of your application "
-            "dependencies anymore, this option has no effect. "
-            "This option can be repeated."
+            "Make sure selected dependencies are upgraded (or downgraded) to "
+            "the latest allowed version. If DEP is not part of your application "
+            "dependencies anymore, this option has no effect."
         ),
     ),
     upgrade_all: bool = typer.Option(
@@ -80,7 +79,7 @@ def sync(
     sync_operation(
         ctx.obj.python,
         upgrade_all,
-        to_upgrade,
+        comma_split(to_upgrade),
         editable,
         extras=[],
         uninstall_unneeded=uninstall_unneeded,

src/pip_deepfreeze/utils.py

@@ -2,7 +2,7 @@
 import subprocess
 from pathlib import Path
 from subprocess import CalledProcessError
-from typing import IO, Any, Dict, Iterator, Optional, Sequence, Union
+from typing import IO, Any, Dict, Iterator, List, Optional, Sequence, Union
 
 import typer
 
@@ -82,3 +82,13 @@ def check_output(
         cmd_str = shlex_join(str(item) for item in cmd)
         log_error(f"Error running: {cmd_str}.")
         raise typer.Exit(1)
+
+
+def comma_split(s: str) -> List[str]:
+    if not s:
+        return []
+    s = s.strip()
+    if not s:
+        return []
+    items = [item.strip() for item in s.split(",")]
+    return [item for item in items if item]

tests/test_utils.py

@@ -6,6 +6,7 @@
 from pip_deepfreeze.utils import (
     check_call,
     check_output,
+    comma_split,
     decrease_verbosity,
     increase_verbosity,
     log_debug,
@@ -82,3 +83,18 @@ def test_check_output(capsys):
         check_output([sys.executable, "-c", "import sys; sys.exit(1)"])
     assert e.value.exit_code == 1
     assert "Error running: " in capsys.readouterr().err
+
+
+@pytest.mark.parametrize(
+    "s, expected",
+    [
+        (None, []),
+        ("", []),
+        ("  ", []),
+        (" a", ["a"]),
+        ("a, b", ["a", "b"]),
+        ("a,,b, c ", ["a", "b", "c"]),
+    ],
+)
+def test_comma_split(s, expected):
+    assert comma_split(s) == expected