tests / fix: Fix v1.13.1 pane spacing issue (#809)

This may negate the fix from #737 (for #667 and #704)
that helped certain layouts.

If a client hasn't yet been attached, 80x24 isn't enough 
to handle workspace building splitting the panes out.

CHANGES

@@ -24,6 +24,34 @@ $ pipx install --suffix=@next 'tmuxp' --pip-args '\--pre' --force
 - Add [flake8-bugbear](https://github.com/PyCQA/flake8-bugbear) (#807)
 - Add [flake8-comprehensions](https://github.com/adamchainz/flake8-comprehensions) (#808)
 
+## tmuxp 1.13.x (2022-09-10)
+
+### Bug fixes
+
+- Layout size has been bumped for those experiencing layout spacing issues
+  (#809, fixes #800)
+
+  If you encounter issues with pane spacing, consider passing an `option` like
+  so:
+
+  ```yaml
+  session_name: main-pane-height
+  start_directory: "~"
+  options:
+    default-size: 999x999
+  windows:
+    - window_name: my window name
+      layout: main-horizontal
+      options:
+        main-pane-height: 30
+      panes:
+        - shell_command: top
+        - shell_command: top
+        - shell_command: top
+        - shell_command: echo "hey"
+        - shell_command: echo "moo"
+  ```
+
 ## tmuxp 1.13.1 (2022-08-21)
 
 ### Bug fixes

tests/fixtures/regressions/issue_800_default_size_many_windows.yaml

@@ -0,0 +1,12 @@
+session_name: many-windows-issue
+windows:
+- window_name: moo
+  layout: main-horizontal
+  panes:
+  - echo hello
+  - echo hello
+  - echo hello
+  - echo hello
+  - echo hello
+  - echo hello
+  - echo hello

tests/test_workspacebuilder.py

@@ -3,22 +3,26 @@
 import pathlib
 import textwrap
 import time
+import typing as t
 
 import pytest
 
 import kaptan
 
 import libtmux
-from libtmux import Window
 from libtmux.common import has_gte_version, has_lt_version
 from libtmux.test import retry_until, temp_session
+from libtmux.window import Window
 from tmuxp import config, exc
 from tmuxp.cli.load import load_plugins
 from tmuxp.workspacebuilder import WorkspaceBuilder
 
 from .constants import EXAMPLE_PATH, FIXTURE_PATH
 from .fixtures import utils as test_utils
 
+if t.TYPE_CHECKING:
+    from libtmux.server import Server
+
 
 def test_split_windows(session):
     yaml_config = test_utils.read_config_file("workspacebuilder/two_pane.yaml")
@@ -1209,11 +1213,100 @@ def height(p):
     def width(p):
         return int(p._info["pane_width"])
 
-    assert height(main_horizontal_pane) > height(panes[0])
+    main_horizontal_pane_height = height(main_horizontal_pane)
+    pane_heights = [height(pane) for pane in panes]
+    # TODO: When libtmux has new pane formatters added, use that to detect top / bottom
+    assert all(
+        main_horizontal_pane_height != pane_height for pane_height in pane_heights
+    ), "The top row should not be the same size as the bottom row (even though it can)"
+    assert all(
+        pane_heights[0] == pane_height for pane_height in pane_heights
+    ), "The bottom row should be uniform height"
     assert width(main_horizontal_pane) > width(panes[0])
 
     def is_almost_equal(x, y):
         return abs(x - y) <= 1
 
     assert is_almost_equal(height(panes[0]), height(panes[1]))
     assert is_almost_equal(width(panes[0]), width(panes[1]))
+
+
+class DefaultSizeNamespaceFixture(t.NamedTuple):
+    test_id: str
+    TMUXP_DEFAULT_SIZE: t.Optional[str]
+    raises: bool
+    confoverrides: t.Dict[str, t.Any]
+
+
+DEFAULT_SIZE_FIXTURES = [
+    DefaultSizeNamespaceFixture(
+        test_id="default-behavior",
+        TMUXP_DEFAULT_SIZE=None,
+        raises=False,
+        confoverrides={},
+    ),
+    DefaultSizeNamespaceFixture(
+        test_id="v1.13.1 default-size-breaks",
+        TMUXP_DEFAULT_SIZE=None,
+        raises=True,
+        confoverrides={"options": {"default-size": "80x24"}},
+    ),
+    DefaultSizeNamespaceFixture(
+        test_id="v1.13.1-option-workaround",
+        TMUXP_DEFAULT_SIZE=None,
+        raises=False,
+        confoverrides={"options": {"default-size": "800x600"}},
+    ),
+]
+
+
+@pytest.mark.parametrize(
+    DefaultSizeNamespaceFixture._fields,
+    DEFAULT_SIZE_FIXTURES,
+    ids=[f.test_id for f in DEFAULT_SIZE_FIXTURES],
+)
+@pytest.mark.skipif(has_lt_version("2.9"), reason="default-size only applies there")
+def test_issue_800_default_size_many_windows(
+    server: "Server",
+    monkeypatch: pytest.MonkeyPatch,
+    test_id: str,
+    TMUXP_DEFAULT_SIZE: t.Optional[str],
+    raises: bool,
+    confoverrides: t.Dict[str, t.Any],
+) -> None:
+    """Recreate default-size issue.
+
+    v1.13.1 added a default-size, but this can break building workspaces with
+    a lot of panes.
+
+    See also: https://github.com/tmux-python/tmuxp/issues/800
+    """
+    yaml_config = test_utils.read_config_file(
+        "regressions/issue_800_default_size_many_windows.yaml"
+    )
+    sconfig = kaptan.Kaptan(handler="yaml")
+    sconfig = sconfig.import_config(yaml_config).get()
+    sconfig = config.expand(sconfig)
+    sconfig = config.trickle(sconfig)
+
+    if isinstance(confoverrides, dict):
+        for k, v in confoverrides.items():
+            sconfig[k] = v
+
+    if TMUXP_DEFAULT_SIZE is not None:
+        monkeypatch.setenv("TMUXP_DEFAULT_SIZE", TMUXP_DEFAULT_SIZE)
+
+    builder = WorkspaceBuilder(sconf=sconfig, server=server)
+
+    if raises:
+        with pytest.raises(Exception):
+            builder.build()
+
+        builder.session.kill_session()
+
+        with pytest.raises(libtmux.exc.LibTmuxException, match="no space for new pane"):
+            builder.build()
+        return
+
+    builder.build()
+    assert len(server.list_sessions()) == 1

tmuxp/workspacebuilder.py

@@ -19,6 +19,10 @@
 
 logger = logging.getLogger(__name__)
 
+DEFAULT_WIDTH = "800"
+DEFAULT_HEIGHT = "600"
+DEFAULT_SIZE = f"{DEFAULT_WIDTH}x{DEFAULT_HEIGHT}"
+
 
 class WorkspaceBuilder:
 
@@ -205,22 +209,21 @@ def build(self, session=None, append=False):
                     "Session name %s is already running." % self.sconf["session_name"]
                 )
             else:
+                new_session_kwargs = {}
                 if "start_directory" in self.sconf:
-                    session = self.server.new_session(
-                        session_name=self.sconf["session_name"],
-                        start_directory=self.sconf["start_directory"],
-                    )
-                else:
-                    session = self.server.new_session(
-                        session_name=self.sconf["session_name"]
-                    )
+                    new_session_kwargs["start_directory"] = self.sconf[
+                        "start_directory"
+                    ]
+                session = self.server.new_session(
+                    session_name=self.sconf["session_name"]
+                )
 
             assert self.sconf["session_name"] == session.name
             assert len(self.sconf["session_name"]) > 0
 
         if has_gte_version("2.9"):
             # Use tmux default session size, overwrite Server::new_session
-            session.set_option("default-size", "80x24")
+            session.set_option("default-size", DEFAULT_SIZE)
 
         self.session = session
         self.server = session.server