stage: resolve stage path before creating the stage (#3630)

Current logic is extremely complex and messy, hiding a lot of bugs
inside. There are pretty much only 2 scenarios for stage creation:

1) `dvc add/import/etc` when dvcfile is created beside the output file
2) `dvc run` when dvcfile is created at the place of execution

both are transparently affected by `--fname` flag. Since we've removed
`--cwd` complexity already, there is no reason to generalize stage path
resolution for those two scenarios.

dvc/repo/add.py

@@ -12,7 +12,7 @@ from ..output.base import OutputDoesNotExistError
 from ..progress import Tqdm
 from ..repo.scm_context import scm_context
 from ..stage import Stage
-from ..utils import LARGE_DIR_SIZE
+from ..utils import LARGE_DIR_SIZE, resolve_paths
 
 logger = logging.getLogger(__name__)
 
@@ -123,9 +123,8 @@ def _create_stages(repo, targets, fname, pbar=None):
         disable=len(targets) < LARGE_DIR_SIZE,
         unit="file",
     ):
-        stage = Stage.create(
-            repo, outs=[out], accompany_outs=True, fname=fname
-        )
+        path, wdir, out = resolve_paths(repo, out)
+        stage = Stage.create(repo, fname or path, wdir=wdir, outs=[out])
         repo._reset()
 
         if not stage:

dvc/repo/imp_url.py

@@ -1,6 +1,9 @@
+import os
+
 from . import locked as locked_repo
 from dvc.repo.scm_context import scm_context
-from dvc.utils import resolve_output
+from dvc.utils import resolve_output, resolve_paths, relpath
+from dvc.utils.fs import path_isin
 
 
 @locked_repo
@@ -9,15 +12,14 @@ def imp_url(self, url, out=None, fname=None, erepo=None, locked=True):
     from dvc.stage import Stage
 
     out = resolve_output(url, out)
+    path, wdir, out = resolve_paths(self, out)
+
+    # NOTE: when user is importing something from within his own repository
+    if os.path.exists(url) and path_isin(os.path.abspath(url), self.root_dir):
+        url = relpath(url, wdir)
 
     stage = Stage.create(
-        self,
-        cmd=None,
-        deps=[url],
-        outs=[out],
-        fname=fname,
-        erepo=erepo,
-        accompany_outs=True,
+        self, fname or path, wdir=wdir, deps=[url], outs=[out], erepo=erepo,
     )
 
     if stage is None:

dvc/repo/run.py

@@ -1,14 +1,30 @@
+import os
+
 from . import locked
 from .scm_context import scm_context
 
 
 @locked
 @scm_context
-def run(self, no_exec=False, **kwargs):
+def run(self, fname=None, no_exec=False, **kwargs):
     from dvc.stage import Stage
 
-    stage = Stage.create(self, **kwargs)
+    outs = (
+        kwargs.get("outs", [])
+        + kwargs.get("outs_no_cache", [])
+        + kwargs.get("metrics", [])
+        + kwargs.get("metrics_no_cache", [])
+        + kwargs.get("outs_persist", [])
+        + kwargs.get("outs_persist_no_cache", [])
+    )
 
+    if outs:
+        base = os.path.basename(os.path.normpath(outs[0]))
+        path = base + Stage.STAGE_FILE_SUFFIX
+    else:
+        path = Stage.STAGE_FILE
+
+    stage = Stage.create(self, fname or path, **kwargs)
     if stage is None:
         return None
 

dvc/stage.py

@@ -7,7 +7,6 @@ import subprocess
 import threading
 
 from functools import wraps
-from itertools import chain
 from funcy import decorator
 
 from voluptuous import Any, Schema, MultipleInvalid
@@ -21,7 +20,6 @@ from dvc.utils import fix_env
 from dvc.utils import relpath
 from dvc.utils.fs import path_isin
 from dvc.utils.collections import apply_diff
-from dvc.utils.fs import contains_symlink_up_to
 from dvc.utils.stage import dump_stage_file
 from dvc.utils.stage import parse_stage
 from dvc.utils.stage import parse_stage_for_update
@@ -418,23 +416,6 @@ class Stage(object):
         except MultipleInvalid as exc:
             raise StageFileFormatError(fname, exc)
 
-    @classmethod
-    def _stage_fname(cls, outs, add):
-        if not outs:
-            return cls.STAGE_FILE
-
-        out = outs[0]
-        fname = out.path_info.name + cls.STAGE_FILE_SUFFIX
-
-        if (
-            add
-            and out.is_in_repo
-            and not contains_symlink_up_to(out.fspath, out.repo.root_dir)
-        ):
-            fname = out.path_info.with_name(fname).fspath
-
-        return fname
-
     @staticmethod
     def _check_stage_path(repo, path, is_wdir=False):
         assert repo is not None
@@ -505,12 +486,20 @@ class Stage(object):
         return True
 
     @staticmethod
-    def create(repo, accompany_outs=False, **kwargs):
+    def create(repo, path, **kwargs):
         wdir = kwargs.get("wdir", None) or os.curdir
-        fname = kwargs.get("fname", None)
+
+        wdir = os.path.abspath(wdir)
+        path = os.path.abspath(path)
+
+        Stage._check_dvc_filename(path)
+
+        Stage._check_stage_path(repo, wdir, is_wdir=kwargs.get("wdir"))
+        Stage._check_stage_path(repo, os.path.dirname(path))
 
         stage = Stage(
             repo=repo,
+            path=path,
             wdir=wdir,
             cmd=kwargs.get("cmd", None),
             locked=kwargs.get("locked", False),
@@ -527,28 +516,6 @@ class Stage(object):
         stage._check_circular_dependency()
         stage._check_duplicated_arguments()
 
-        if not fname:
-            fname = Stage._stage_fname(stage.outs, accompany_outs)
-        stage._check_dvc_filename(fname)
-
-        # Autodetecting wdir for add, we need to create outs first to do that,
-        # so we start with wdir = . and remap out paths later.
-        if accompany_outs and kwargs.get("wdir") is None:
-            wdir = os.path.dirname(fname)
-
-            for out in chain(stage.outs, stage.deps):
-                if out.is_in_repo:
-                    out.def_path = relpath(out.path_info, wdir)
-
-        wdir = os.path.abspath(wdir)
-        path = os.path.abspath(fname)
-
-        Stage._check_stage_path(repo, wdir, is_wdir=kwargs.get("wdir"))
-        Stage._check_stage_path(repo, os.path.dirname(path))
-
-        stage.wdir = wdir
-        stage.path = path
-
         ignore_build_cache = kwargs.get("ignore_build_cache", False)
 
         # NOTE: remove outs before we check build cache

dvc/utils/__init__.py

@@ -344,6 +344,32 @@ def resolve_output(inp, out):
     return out
 
 
+def resolve_paths(repo, out):
+    from ..stage import Stage
+    from ..path_info import PathInfo
+    from .fs import contains_symlink_up_to
+
+    abspath = os.path.abspath(out)
+    dirname = os.path.dirname(abspath)
+    base = os.path.basename(os.path.normpath(out))
+
+    # NOTE: `out` might not exist yet, so using `dirname`(aka `wdir`) to check
+    # if it is a local path.
+    if (
+        os.path.exists(dirname)  # out might not exist yet, so
+        and PathInfo(abspath).isin_or_eq(repo.root_dir)
+        and not contains_symlink_up_to(abspath, repo.root_dir)
+    ):
+        wdir = dirname
+        out = base
+    else:
+        wdir = os.getcwd()
+
+    path = os.path.join(wdir, base + Stage.STAGE_FILE_SUFFIX)
+
+    return (path, wdir, out)
+
+
 def format_link(link):
     return "<{blue}{link}{nc}>".format(
         blue=colorama.Fore.CYAN, link=link, nc=colorama.Fore.RESET

tests/unit/test_stage.py

@@ -7,7 +7,6 @@ import mock
 import pytest
 
 from dvc.dependency.repo import DependencyREPO
-from dvc.path_info import PathInfo
 from dvc.stage import Stage
 from dvc.stage import StageUpdateError
 
@@ -61,15 +60,6 @@ class TestPathConversion(TestCase):
         self.assertEqual(stage.dumpd()["wdir"], "../..")
 
 
-@pytest.mark.parametrize("add", [True, False])
-def test_stage_fname(add):
-    out = mock.Mock()
-    out.is_in_repo = False
-    out.path_info = PathInfo("path/to/out.txt")
-    fname = Stage._stage_fname([out], add)
-    assert fname == "out.txt.dvc"
-
-
 def test_stage_update(mocker):
     dep = DependencyREPO({"url": "example.com"}, None, "dep_path")
     mocker.patch.object(dep, "update", return_value=None)