sidebar: framed like a pane, and in compact mode framed *with* it (tab_bar_chrome)

A list of tabs sitting in bare columns beside a framed layout reads as
text that wandered in from outside. So the sidebar gets a frame of its
own -- and in compact mode not its own: its inner vertical lands on the
tab area's ring column, and because the lines are strokes that union
with whatever is already in the cell, the corners become tees without
anyone computing a junction. The sidebar and the layout come out as one
figure, which is the whole point.

Classic mode gets a free-standing frame in the idle frame colour,
rounded or square with everything else. The frame costs a column each
side and a row top and bottom, taken from the sidebar's own budget --
and dropped entirely, before the list is, when the sidebar is too small
to afford it: chrome must not displace what it is chrome for.

The content box (cx/cw) now feeds the labels, the status rows, their
hits and the truncation budget alike, so the frame cannot disagree with
where the clicks land.

1 files changed, 116 insertions, 45 deletions

diff --git a/tests/test_tab_bar.py b/tests/test_tab_bar.py
index 47feba6..850192d 100644
--- a/tests/test_tab_bar.py
+++ b/tests/test_tab_bar.py
@@ -25,54 +25,65 @@ def _cfg(text):
 W = 18
 LEFT = _cfg(f'tab_bar_side "left"\ntab_bar_width {W}\n')
 RIGHT = _cfg(f'tab_bar_side "right"\ntab_bar_width {W}\n')
+BARE = _cfg(f'tab_bar_side "left"\ntab_bar_width {W}\ntab_bar_chrome false\n')
+
+# With tab_bar_chrome (the default) the frame takes a column each side and a
+# row top and bottom: content runs x 1..16, and gap 1 + frame 1 + pad 1 puts
+# the first tab on row 3. CX/CW/Y0 are that content box, so a geometry change
+# is one edit here rather than thirty coordinates below.
+CX, CW, Y0 = 1, W - 2, 3
 
 SH = ["/bin/sh", "-c", "stty raw -echo; cat"]
 
 
+def _row(snap, y):
+    """The sidebar's content on a row, without the frame either side."""
+    return snap.line(y)[CX : CX + CW]
+
+
 def test_left_sidebar_reserves_columns():
     with Session(SH, cols=90, rows=20, config=LEFT) as s:
         s.settle(30)
         snap = s.snapshot()
-        # gap 1 + tab_bar_pad 1 (the defaults): the first tab is row 2.
         check(
             "the first tab is a row in the sidebar",
-            snap.hit_at(1, 2) == "tab:1",
-            str(snap.hit_at(1, 2)),
+            snap.hit_at(CX, Y0) == "tab:1",
+            str(snap.hit_at(CX, Y0)),
         )
         check(
             "the whole row is the target, not just the label",
-            snap.hit_at(W - 1, 2) == "tab:1",
-            str(snap.hit_at(W - 1, 2)),
+            snap.hit_at(CX + CW - 1, Y0) == "tab:1",
+            str(snap.hit_at(CX + CW - 1, Y0)),
         )
         check(
             "the + sits on the row after the last tab",
-            snap.hit_at(1, 3) == "newtab",
-            str(snap.hit_at(1, 3)),
+            snap.hit_at(CX, Y0 + 1) == "newtab",
+            str(snap.hit_at(CX, Y0 + 1)),
         )
         p = s.pane(0)
         check("panes give up the sidebar's columns", p["x"] >= W, str(p["x"]))
-        # rows 20, status line on 19: the count takes the sidebar's last row.
+        # rows 20, status line on 19, the frame's bottom line on 18.
         check(
             "the pane count moved to the sidebar's bottom",
-            "1 pane" in snap.line(18)[:W],
-            repr(snap.line(18)[:W]),
+            "1 pane" in _row(snap, 17),
+            repr(_row(snap, 17)),
         )
 
 
 def test_sidebar_rows_click_like_the_strip():
     with Session(SH, cols=90, rows=20, config=LEFT) as s:
         s.settle(30)
-        s.click(1, 3)  # the + row: a new tab, which becomes the active one
+        s.click(CX, Y0 + 1)  # the + row: a new tab, which becomes the active one
         s.until(lambda _: len(s.tabs()) == 2)
         check("the + row makes a tab", len(s.tabs()) == 2, str(len(s.tabs())))
         check("...and it is the one you are in", s.tabs()[1]["active"], str(s.tabs()))
         snap = s.snapshot()
         check(
             "the new tab is the next row down",
-            snap.hit_at(1, 3) == "tab:2",
-            str(snap.hit_at(1, 3)),
+            snap.hit_at(CX, Y0 + 1) == "tab:2",
+            str(snap.hit_at(CX, Y0 + 1)),
         )
-        s.click(1, 2)  # the first tab's row
+        s.click(CX, Y0)  # the first tab's row
         s.until(lambda _: s.tabs()[0]["active"])
         check("clicking a row selects that tab", s.tabs()[0]["active"], str(s.tabs()))
 
@@ -84,8 +95,8 @@ def test_right_sidebar_takes_the_other_edge():
         x0 = 90 - W
         check(
             "the first tab is a row on the right edge",
-            snap.hit_at(x0 + 1, 2) == "tab:1",
-            str(snap.hit_at(x0 + 1, 2)),
+            snap.hit_at(x0 + CX, Y0) == "tab:1",
+            str(snap.hit_at(x0 + CX, Y0)),
         )
         p = s.pane(0)
         check(
@@ -100,16 +111,16 @@ def test_pad_pushes_the_list_down():
     with Session(SH, cols=90, rows=20, config=pad) as s:
         s.settle(30)
         snap = s.snapshot()
-        # gap 1 + pad 3: the first tab is on row 4, and the rows above are air.
+        # Two rows further down than the default pad of 1.
         check(
             "the pad rows are not targets",
-            snap.hit_at(1, 1) is None and snap.hit_at(1, 3) is None,
-            f"{snap.hit_at(1, 1)} / {snap.hit_at(1, 3)}",
+            snap.hit_at(CX, Y0) is None and snap.hit_at(CX, Y0 + 1) is None,
+            f"{snap.hit_at(CX, Y0)} / {snap.hit_at(CX, Y0 + 1)}",
         )
         check(
             "the first tab starts below the pad",
-            snap.hit_at(1, 4) == "tab:1",
-            str(snap.hit_at(1, 4)),
+            snap.hit_at(CX, Y0 + 2) == "tab:1",
+            str(snap.hit_at(CX, Y0 + 2)),
         )
         p = s.pane(0)
         check(
@@ -134,21 +145,21 @@ def test_status_rows_sit_under_their_tab():
         snap = s.snapshot()
         check(
             "a pane's OSC status is a row under its tab",
-            "building 3/7" in snap.line(3)[:W],
-            repr(snap.line(3)[:W]),
+            "building 3/7" in _row(snap, Y0 + 1),
+            repr(_row(snap, Y0 + 1)),
         )
         check(
             "the other tab moved down to make room",
-            snap.hit_at(1, 4) == "tab:2",
-            str(snap.hit_at(1, 4)),
+            snap.hit_at(CX, Y0 + 2) == "tab:2",
+            str(snap.hit_at(CX, Y0 + 2)),
         )
         check(
             "the row is a door to the pane that said it",
-            snap.hit_at(2, 3) == f"find:{pane}",
-            str(snap.hit_at(2, 3)),
+            snap.hit_at(CX + 1, Y0 + 1) == f"find:{pane}",
+            str(snap.hit_at(CX + 1, Y0 + 1)),
         )
         # We are in tab 2: clicking the status row is a cross-tab jump.
-        s.click(2, 3)
+        s.click(CX + 1, Y0 + 1)
         s.until(lambda _: s.tabs()[0]["active"])
         check("clicking it selects that tab", s.tabs()[0]["active"], str(s.tabs()))
         check(
@@ -169,18 +180,18 @@ def test_status_cap_spends_its_last_row_on_the_ellipsis():
         snap = s.snapshot()
         check(
             "over the cap, the row says there was more",
-            snap.line(3)[:W].strip() == "\u2026",
-            repr(snap.line(3)[:W]),
+            _row(snap, Y0 + 1).strip() == "\u2026",
+            repr(_row(snap, Y0 + 1)),
         )
         check(
             "an ellipsis is not a door",
-            snap.hit_at(2, 3) is None,
-            str(snap.hit_at(2, 3)),
+            snap.hit_at(CX + 1, Y0 + 1) is None,
+            str(snap.hit_at(CX + 1, Y0 + 1)),
         )
         check(
             "and only the cap's rows were spent",
-            snap.hit_at(1, 4) == "newtab",
-            str(snap.hit_at(1, 4)),
+            snap.hit_at(CX, Y0 + 2) == "newtab",
+            str(snap.hit_at(CX, Y0 + 2)),
         )
 
 
@@ -188,7 +199,7 @@ def test_a_long_status_is_cut_and_says_so():
     with Session(SH, cols=90, rows=20, config=LEFT) as s:
         s.settle(30)
         _status(s, "a status far too long for the sidebar")
-        row = s.snapshot().line(3)[:W]
+        row = _row(s.snapshot(), Y0 + 1)
         check(
             "the status stops at the sidebar's edge", row.endswith("\u2026"), repr(row)
         )
@@ -199,8 +210,8 @@ def test_a_dead_pane_reports_its_exit_instead():
     # and the point here is the words, not the (already tested) truncation.
     kept = _cfg('tab_bar_side "left"\ntab_bar_width 24\nkeep_dead "all"\n')
     with Session(["/bin/sh", "-c", "exit 3"], cols=90, rows=20, config=kept) as s:
-        s.until(lambda snap: "exited" in snap.line(3))
-        row = s.snapshot().line(3)[:24]
+        s.until(lambda snap: "exited" in snap.line(Y0 + 1))
+        row = s.snapshot().line(Y0 + 1)[CX : CX + 22]
         check("how it died replaces what it last said", "status 3" in row, repr(row))
 
 
@@ -208,7 +219,7 @@ def test_an_unnamed_tab_borrows_its_directory():
     cd = ["/bin/sh", "-c", "cd /tmp && stty raw -echo; cat"]
     with Session(cd, cols=90, rows=20, config=LEFT) as s:
         s.settle(60)
-        row = s.snapshot().line(2)[:W]
+        row = _row(s.snapshot(), Y0)
         check("the label is the focused pane's dir", "1:tmp" in row, repr(row))
 
 
@@ -218,20 +229,77 @@ def test_a_real_name_beats_the_derived_one():
     lay.close()
     with Session(SH, cols=90, rows=20, config=LEFT, layout=lay.name) as s:
         s.settle(60)
-        row = s.snapshot().line(2)[:W]
+        row = _row(s.snapshot(), Y0)
         check("a declared name is not second-guessed", "1:api" in row, repr(row))
 
 
 def test_the_borrowed_name_follows_a_cd():
     loop = ["/bin/sh", "-c", 'cd /tmp && while IFS= read -r l; do eval "$l"; done']
     with Session(loop, cols=90, rows=20, config=LEFT) as s:
-        s.until(lambda snap: "1:tmp" in snap.line(2))
+        s.until(lambda snap: "1:tmp" in snap.line(Y0))
         s.send(r"cd /home\n")
-        s.until(lambda snap: "1:home" in snap.line(2))
-        row = s.snapshot().line(2)[:W]
+        s.until(lambda snap: "1:home" in snap.line(Y0))
+        row = _row(s.snapshot(), Y0)
         check("the kernel's answer moves the label", "1:home" in row, repr(row))
 
 
+def test_the_sidebar_is_framed_like_a_pane():
+    with Session(SH, cols=90, rows=20, config=LEFT) as s:
+        s.settle(40)
+        snap = s.snapshot()
+        top, bottom = snap.line(1), snap.line(18)
+        check("a frame runs round the list", top[0] in "\u256d\u250c", repr(top[:W]))
+        check(
+            "...closed at the bottom, above the status line",
+            bottom[0] in "\u2570\u2514",
+            repr(bottom[:W]),
+        )
+        check(
+            "and the list sits inside it",
+            snap.line(Y0)[0] == "\u2502" and snap.line(Y0)[CX + CW] == "\u2502",
+            repr(snap.line(Y0)[:W]),
+        )
+
+
+def test_compact_shares_its_lines_with_the_ring():
+    """The point of the chrome: one figure, not a box beside a box.
+
+    The sidebar's inner vertical *is* the tab area's ring column, so the
+    stroke union turns the ring's top-left corner into a tee -- nobody
+    computes that, it falls out of the same machinery the dividers use.
+    """
+    conf = _cfg(f'compact true\ntab_bar_side "left"\ntab_bar_width {W}\n')
+    with Session(SH, cols=90, rows=20, config=conf) as s:
+        s.settle(40)
+        snap = s.snapshot()
+        check(
+            "the sidebar meets the ring in a junction, not a corner",
+            snap.line(0)[W] == "\u252c",
+            repr(snap.line(0)[: W + 2]),
+        )
+        check(
+            "...and again at the bottom",
+            snap.line(18)[W] == "\u2534",
+            repr(snap.line(18)[: W + 2]),
+        )
+
+
+def test_chrome_false_gives_the_columns_back():
+    with Session(SH, cols=90, rows=20, config=BARE) as s:
+        s.settle(40)
+        snap = s.snapshot()
+        check(
+            "no frame: the list starts in the first column",
+            snap.hit_at(0, 2) == "tab:1",
+            str(snap.hit_at(0, 2)),
+        )
+        check(
+            "and the whole width is the target",
+            snap.hit_at(W - 1, 2) == "tab:1",
+            str(snap.hit_at(W - 1, 2)),
+        )
+
+
 def test_narrow_terminal_falls_back_to_top():
     # 40 < width + min_pane cols + 4: the sidebar would leave no room for the
     # pane it is chrome for, so the strip goes back to the top row.
@@ -251,11 +319,11 @@ def test_growing_back_restores_the_sidebar():
     with Session(SH, cols=40, rows=20, config=LEFT) as s:
         s.settle(30)
         s.resize(90, 20)
-        s.until(lambda snap: snap.hit_at(1, 2) == "tab:1")
+        s.until(lambda snap: snap.hit_at(CX, Y0) == "tab:1")
         check(
             "a resize moves the bar without anyone storing state",
-            s.snapshot().hit_at(1, 2) == "tab:1",
-            str(s.snapshot().hit_at(1, 2)),
+            s.snapshot().hit_at(CX, Y0) == "tab:1",
+            str(s.snapshot().hit_at(CX, Y0)),
         )
         p = s.pane(0)
         check("and the panes give the columns back", p["x"] >= W, str(p["x"]))
@@ -273,6 +341,9 @@ if __name__ == "__main__":
     test_an_unnamed_tab_borrows_its_directory()
     test_a_real_name_beats_the_derived_one()
     test_the_borrowed_name_follows_a_cd()
+    test_the_sidebar_is_framed_like_a_pane()
+    test_compact_shares_its_lines_with_the_ring()
+    test_chrome_false_gives_the_columns_back()
     test_narrow_terminal_falls_back_to_top()
     test_growing_back_restores_the_sidebar()
     sys.exit(report())