slosh: layout files are *.layout, not *.layout.kdl

The old name argued that the extension should say how to read the
file. The argument lost to a collision: zellij speaks the same KDL
syntax under that same extension with a different schema, and to
anyone arriving from there .kdl said *whose* file it is -- naming the
wrong owner is worse than not naming the parser. So a layout is
x.layout, a project's is slosh.layout, the name says what the file is
and --check says how it was read. (It is still KDL underneath; point
your editor's highlighting at *.layout.)

Nobody's checked-in workspace vanishes on upgrade: the project scan
still finds slosh.layout.kdl, never writes it, and where both
spellings exist the new one wins, because two files disagreeing needs
one answer. The unparseable-file heuristic in --check learned the new
suffix -- it matched '.layout.' with a trailing dot, which the new
name no longer has.

The webdemo overlay moves with it (demo.layout), rebuilt and
boot-checked.

4 files changed, 43 insertions, 17 deletions

diff --git a/tests/test_config.py b/tests/test_config.py
index cb80829..84d73c7 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -713,8 +713,8 @@ def test_the_shipped_files_are_what_they_claim():
     check(
         "config/config.kdl lints clean", conf.returncode == 0, repr(conf.stderr[:160])
     )
-    lay = root / "config" / "example.layout.kdl"
-    check("the example layout is named `*.layout.kdl`", lay.exists(), str(lay))
+    lay = root / "config" / "example.layout"
+    check("the example layout is named `*.layout`", lay.exists(), str(lay))
     exl = subprocess.run([BIN, "--check", str(lay)], capture_output=True, text=True)
     check("and it lints clean as a layout", exl.returncode == 0, repr(exl.stderr[:200]))
     out = subprocess.run(
diff --git a/tests/test_layout_files.py b/tests/test_layout_files.py
index 7bc8285..611c83d 100644
--- a/tests/test_layout_files.py
+++ b/tests/test_layout_files.py
@@ -287,7 +287,7 @@ def test_bad_layouts():
         r = s.api("apply-layout", kdl="layout { }")
         check("a layout with no tabs is refused", not r["ok"], str(r))
 
-        r = s.api("apply-layout", path="/nonexistent/layout.kdl")
+        r = s.api("apply-layout", path="/nonexistent/x.layout")
         check("a missing file is refused", not r["ok"], str(r))
 
         check(
diff --git a/tests/test_portable_layouts.py b/tests/test_portable_layouts.py
index 5b3ccc0..12229ba 100644
--- a/tests/test_portable_layouts.py
+++ b/tests/test_portable_layouts.py
@@ -27,7 +27,7 @@ def project(name, text):
     root = tempfile.mkdtemp(prefix="slosh-proj-")
     d = os.path.join(root, name)
     os.makedirs(os.path.join(d, "src"))
-    path = os.path.join(d, "slosh.layout.kdl")
+    path = os.path.join(d, "slosh.layout")
     with open(path, "w") as f:
         f.write(text)
     return d, path
@@ -234,7 +234,7 @@ layout {
     )
     with Session(SH, layout=path) as s:
         first = s.api("dump-layout", tab=s.tabs()[0]["id"], relative_to=d)["kdl"]
-        again = os.path.join(d, "again.layout.kdl")
+        again = os.path.join(d, "again.layout")
         with open(again, "w") as f:
             f.write(first)
     with Session(SH, layout=again) as s2:
@@ -278,7 +278,7 @@ layout {
         check("it names: " + want, want in said, said)
     check(
         "every problem carries a file and a line",
-        said.count("slosh.layout.kdl:") >= 6,
+        said.count("slosh.layout:") >= 6,
         said,
     )
 
@@ -325,7 +325,7 @@ def test_a_syntax_error_in_a_layout_is_reported_as_the_layout_it_is():
     code, said = lint(path)
     check(
         "it says which file and which line the syntax broke on",
-        "slosh.layout.kdl:" in said and "unclosed" in said,
+        "slosh.layout:" in said and "unclosed" in said,
         said,
     )
     check(
diff --git a/tests/test_workspaces.py b/tests/test_workspaces.py
index 3a0163d..d691fa2 100644
--- a/tests/test_workspaces.py
+++ b/tests/test_workspaces.py
@@ -1,6 +1,6 @@
 """Workspaces: projects on disk, and the tabs they open as.
 
-A *project* is a directory somebody works in -- one with a `slosh.layout.kdl`
+A *project* is a directory somebody works in -- one with a `slosh.layout`
 saying what it needs, or a `.git` and nothing said yet. A *workspace* is the tab
 it occupies here, and membership is that tab's `purpose` in the `project:`
 namespace, so there is no second answer to "what is this tab" and a dumped
@@ -48,7 +48,7 @@ def roots(**projects):
         if what == "git":
             os.makedirs(os.path.join(d, ".git"), exist_ok=True)
         elif what:
-            with open(os.path.join(d, "slosh.layout.kdl"), "w") as f:
+            with open(os.path.join(d, "slosh.layout"), "w") as f:
                 f.write(what)
     cfg = os.path.join(base, "config.kdl")
     with open(cfg, "w") as f:
@@ -70,6 +70,32 @@ def session(cfg, argv=None, **kw):
 # ---- discovery -------------------------------------------------------------
 
 
+def test_the_old_layout_spelling_is_still_found_never_preferred():
+    """`slosh.layout.kdl` was the name before the extension collided with
+    zellij's. A checked-in workspace must not vanish on upgrade, so the scan
+    still finds the old spelling -- and where both exist, the new one wins,
+    because two files disagreeing needs one answer."""
+    base, dev, cfg = roots(old=None, both=None)
+    with open(os.path.join(dev, "old", "slosh.layout.kdl"), "w") as f:
+        f.write(API_LAYOUT)
+    with open(os.path.join(dev, "both", "slosh.layout"), "w") as f:
+        f.write(API_LAYOUT)
+    with open(os.path.join(dev, "both", "slosh.layout.kdl"), "w") as f:
+        f.write(API_LAYOUT)
+    with session(cfg) as s:
+        got = {w["name"]: w for w in s.api("workspaces")["workspaces"]}
+        check(
+            "a project with only the old name is still a project",
+            "old" in got and got["old"]["layout"].endswith("slosh.layout.kdl"),
+            str(got.get("old")),
+        )
+        check(
+            "where both spellings exist the new one wins",
+            "both" in got and got["both"]["layout"].endswith("/slosh.layout"),
+            str(got.get("both")),
+        )
+
+
 def test_a_project_is_a_layout_file_or_a_git():
     """Both, because `~/dev` with forty checkouts and three layout files would
     otherwise be a picker with three rows -- and a `.git` is exactly the project
@@ -82,7 +108,7 @@ def test_a_project_is_a_layout_file_or_a_git():
         check("a directory that is neither is not listed", "notes" not in got, str(got))
         check(
             "the declared one names its file",
-            got["api"]["layout"].endswith("slosh.layout.kdl"),
+            got["api"]["layout"].endswith("slosh.layout"),
             str(got["api"]),
         )
         check(
@@ -208,7 +234,7 @@ def test_a_project_with_no_layout_opens_as_your_project_layout():
     bind to whichever project is opening -- not to the directory the file lives
     in, which would open every project in ~/.config."""
     base, dev, cfg = roots(web="git")
-    shared = os.path.join(base, "project.layout.kdl")
+    shared = os.path.join(base, "project.layout")
     with open(shared, "w") as f:
         f.write('layout { tab { pane purpose="agent:main"; pane cwd="src" } }\n')
     with open(cfg, "a") as f:
@@ -303,7 +329,7 @@ def test_saving_a_tab_writes_a_portable_layout_file():
         saved = s.api("save-workspace")
         check(
             "it says where it wrote",
-            saved["path"] == os.path.join(dev, "web", "slosh.layout.kdl"),
+            saved["path"] == os.path.join(dev, "web", "slosh.layout"),
             str(saved),
         )
         check(
@@ -554,7 +580,7 @@ def test_every_verb_has_a_bare_form():
         wrote = bare1(s, "save-workspace")
         check(
             "save-workspace names the file it wrote",
-            "slosh.layout.kdl" in wrote,
+            "slosh.layout" in wrote,
             repr(wrote),
         )
         check(
@@ -588,7 +614,7 @@ def test_a_dumped_session_restores_workspace_membership():
     with session(cfg) as s:
         r = s.api("open-workspace", name="api")
         whole = s.api("dump-layout")["kdl"]
-    restored = os.path.join(base, "session.layout.kdl")
+    restored = os.path.join(base, "session.layout")
     with open(restored, "w") as f:
         f.write(whole)
     with Session(SH, config=cfg, layout=restored, cols=100, rows=30) as s2:
@@ -609,7 +635,7 @@ def test_the_picker_lists_projects_and_opens_one():
         s.key("w")
         screen = s.snapshot().screen()
         check("it is titled as projects", "projects" in screen, screen)
-        check("a declared project shows its file", "slosh.layout.kdl" in screen, screen)
+        check("a declared project shows its file", "slosh.layout" in screen, screen)
         check("and one without says so", "no layout" in screen, screen)
 
         s.send("web")
@@ -649,11 +675,11 @@ def test_saving_from_the_keyboard_says_what_it_did():
         s.api("open-workspace", name="web")
         s.key("W")
         screen = s.snapshot().screen()
-        check("the toast names the file", "slosh.layout.kdl" in screen, screen)
+        check("the toast names the file", "slosh.layout" in screen, screen)
         check("and counts what it wrote", "1 pane" in screen, screen)
         check(
             "the file is there",
-            os.path.exists(os.path.join(dev, "web", "slosh.layout.kdl")),
+            os.path.exists(os.path.join(dev, "web", "slosh.layout")),
             screen,
         )