#21871 Running `pants fmt` with `--changed-since` changes result vs directly listing target Issue created by mattalbr Describe the bug

vscode ➜ /workspace (pipeline_next) $ pants lint datasci/pipeline/test/test_model_assets.py 
00:33:37.94 [INFO] Completed: Format with Black - black made no changes.
00:33:37.94 [INFO] Completed: Format with isort - isort made no changes.

✓ black succeeded.
✓ isort succeeded.

vscode ➜ /workspace (pipeline_next) $ pants fmt datasci/pipeline/test/test_model_assets.py 
00:33:48.51 [INFO] Completed: Format with Black - black made no changes.
00:33:48.51 [INFO] Completed: Format with isort - isort made no changes.

✓ black made no changes.
✓ isort made no changes.

vscode ➜ /workspace (pipeline_next) $ pants lint --changed-since=upstream/dev
00:34:19.84 [WARN] Completed: Format with isort - isort made changes.
  datasci/pipeline/delfina_data/model_assets/model_publishers.py
  datasci/pipeline/delfina_data/models.py
  datasci/pipeline/test/test_model_assets.py
00:34:19.84 [INFO] Completed: Format with Black - black made no changes.
00:34:19.84 [INFO] Completed: Format with Black - black made no changes.
00:34:19.84 [INFO] Completed: Format with isort - isort made no changes.
00:34:19.84 [INFO] Completed: Format with Black - black made no changes.
00:34:19.84 [INFO] Completed: Format with isort - isort made no changes.
00:34:19.84 [INFO] Completed: Format with Black - black made no changes.
00:34:19.84 [INFO] Completed: Format with Black - black made no changes.
00:34:19.84 [INFO] Completed: Format with isort - isort made no changes.
00:34:19.84 [INFO] Completed: Format with isort - isort made no changes.

✓ black succeeded.
✕ isort failed.

(One or more formatters failed. Run `pants fmt` to fix.)

vscode ➜ /workspace (pipeline_next) $ pants fmt --changed-since=upstream/dev
00:34:28.05 [INFO] Completed: Format with Black - black made no changes.
00:34:28.05 [INFO] Completed: Format with isort - isort made no changes.
00:34:28.05 [INFO] Completed: Format with Black - black made no changes.
00:34:28.05 [INFO] Completed: Format with isort - isort made no changes.
00:34:28.05 [INFO] Completed: Format with isort - isort made no changes.
00:34:28.05 [WARN] Completed: Format with isort - isort made changes.
  datasci/pipeline/delfina_data/model_assets/model_publishers.py
  datasci/pipeline/delfina_data/models.py
  datasci/pipeline/test/test_model_assets.py
00:34:28.05 [INFO] Completed: Format with Black - black made no changes.
00:34:28.05 [INFO] Completed: Format with Black - black made no changes.

✓ black made no changes.
+ isort made changes.

As you can see, linting the file and fmting the file both returned green, until running with --changed-since after which they made edits. FWIW, I think the --changed-since output is correct, and I'm surprised the imports aren't getting reordered without it. imports before:

from concurrent.futures import as_completed
from datetime import datetime
from typing import NamedTuple

import dagster as dg
import pandera.typing.polars as pt
import polars as pl
from backend import models as gaia_models
from backend import schemas as gaia_schemas
from google.cloud import pubsub_v1

from .. import decorators as dd
from ..models import make_dagster_type
from ..models import ModelResults
from ..models import PublishResults
from ..pipeline_checks.asset_checks import *

imports after:

from concurrent.futures import as_completed
from datetime import datetime
from typing import NamedTuple

import dagster as dg
import pandera.typing.polars as pt
import polars as pl
from google.cloud import pubsub_v1

from backend import models as gaia_models
from backend import schemas as gaia_schemas

from .. import decorators as dd
from ..models import make_dagster_type
from ..models import ModelResults
from ..models import PublishResults
from ..pipeline_checks.asset_checks import *

Pants version 2.23.1 OS MacOS and Ubuntu Additional info [isort] args = [ "--profile=black", "-l", "100", "--force-single-line-imports", "--force-alphabetical-sort-within-sections", "--single-line-exclusions=typing", ] interpreter_constraints = [ "CPython>=3.11,<4" ] install_from_resolve = "python-default" # 5.13.2 pantsbuild/pants