plots templates: change ui to not dump to file

Update dvc/commands/plots.py

Co-authored-by: David de la Iglesia Castro <[email protected]>

Update tests/unit/command/test_plots.py

Co-authored-by: David de la Iglesia Castro <[email protected]>

Update dvc/commands/plots.py

Co-authored-by: Paweł Redzyński <[email protected]>

fixed test

dvc/commands/plots.py

@@ -223,31 +223,22 @@ class CmdPlotsModify(CmdPlots):
 
 
 class CmdPlotsTemplates(CmdBase):
-    TEMPLATES_CHOICES = [
-        "simple",
-        "linear",
-        "confusion",
-        "confusion_normalized",
-        "scatter",
-        "smooth",
-        "bar_horizontal_sorted",
-        "bar_horizontal",
-    ]
-
     def run(self):
-        from dvc_render.vega_templates import dump_templates
+        from dvc.exceptions import InvalidArgumentError
+        from dvc_render.vega_templates import TEMPLATES
 
         try:
-            out = (
-                os.path.join(os.getcwd(), self.args.out)
-                if self.args.out
-                else self.repo.plots.templates_dir
-            )
+            target = self.args.template
+            if target:
+                for template in TEMPLATES:
+                    if target == template.DEFAULT_NAME:
+                        ui.write(json.dumps(template.DEFAULT_CONTENT))
+                        return 0
+                raise InvalidArgumentError(f"Unexpected template: {target}.")
 
-            targets = [self.args.target] if self.args.target else None
-            dump_templates(output=out, targets=targets)
-            templates_path = os.path.relpath(out, os.getcwd())
-            ui.write(f"Templates have been written into '{templates_path}'.")
+            else:
+                for template in TEMPLATES:
+                    ui.write(template.DEFAULT_NAME)
 
             return 0
         except DvcException:
@@ -357,8 +348,7 @@ def add_parser(subparsers, parent_parser):
     plots_modify_parser.set_defaults(func=CmdPlotsModify)
 
     TEMPLATES_HELP = (
-        "Write built-in plots templates to a directory "
-        "(.dvc/plots by default)."
+        "List built-in plots templates or show JSON specification for one."
     )
     plots_templates_parser = plots_subparsers.add_parser(
         "templates",
@@ -368,13 +358,14 @@ def add_parser(subparsers, parent_parser):
         formatter_class=argparse.RawDescriptionHelpFormatter,
     )
     plots_templates_parser.add_argument(
-        "target",
+        "template",
         default=None,
         nargs="?",
-        choices=CmdPlotsTemplates.TEMPLATES_CHOICES,
-        help="Template to write. Writes all templates by default.",
+        help=(
+            "Template for which to show JSON specification. "
+            "List all template names by default."
+        ),
     )
-    _add_output_argument(plots_templates_parser, typ="templates")
     plots_templates_parser.set_defaults(func=CmdPlotsTemplates)
 
 

tests/unit/command/test_plots.py

@@ -4,7 +4,6 @@ import posixpath
 from pathlib import Path
 
 import pytest
-from funcy import pluck_attr
 
 from dvc.cli import parse_args
 from dvc.commands.plots import CmdPlotsDiff, CmdPlotsShow, CmdPlotsTemplates
@@ -348,39 +347,38 @@ def test_plots_diff_json(dvc, mocker, capsys):
     render_mock.assert_not_called()
 
 
-@pytest.mark.parametrize("target", (("t1"), (None)))
-def test_plots_templates(tmp_dir, dvc, mocker, capsys, target):
-    assert not os.path.exists(dvc.plots.templates_dir)
-    mocker.patch(
-        "dvc.commands.plots.CmdPlotsTemplates.TEMPLATES_CHOICES",
-        ["t1", "t2"],
-    )
+@pytest.mark.parametrize(
+    "target,expected_out,expected_rtn",
+    (("t1", "\"{'t1'}\"", 0), (None, "t1\nt2", 0), ("t3", "", 1)),
+)
+def test_plots_templates(
+    dvc, mocker, capsys, target, expected_out, expected_rtn
+):
+    t1 = mocker.Mock()
+    t1.DEFAULT_NAME = "t1"
+    t1.DEFAULT_CONTENT = "{'t1'}"
 
-    arguments = ["plots", "templates", "--out", "output"]
+    t2 = mocker.Mock()
+    t2.DEFAULT_NAME = "t2"
+    t2.DEFAULT_CONTENT = "{'t2'}"
+
+    mocker.patch("dvc_render.vega_templates.TEMPLATES", [t1, t2])
+
+    arguments = ["plots", "templates"]
     if target:
         arguments += [target]
 
     cli_args = parse_args(arguments)
     assert cli_args.func == CmdPlotsTemplates
 
-    dump_mock = mocker.patch("dvc_render.vega_templates.dump_templates")
     cmd = cli_args.func(cli_args)
 
-    assert cmd.run() == 0
+    rtn = cmd.run()
+
     out, _ = capsys.readouterr()
 
-    dump_mock.assert_called_once_with(
-        output=os.path.abspath("output"), targets=[target] if target else None
-    )
-    assert "Templates have been written into 'output'." in out
-
-
-def test_plots_templates_choices(tmp_dir, dvc):
-    from dvc_render import TEMPLATES
-
-    assert CmdPlotsTemplates.TEMPLATES_CHOICES == list(
-        pluck_attr("DEFAULT_NAME", TEMPLATES)
-    )
+    assert out.strip() == expected_out
+    assert rtn == expected_rtn
 
 
 @pytest.mark.parametrize("split", (True, False))