fix: keep Memory label visible above the memory graph

demos/tui_capture_2026-09-11-memory.md

@@ -0,0 +1,76 @@
+# Memory-label TUI capture — 2026-09-11
+
+New capture pair showing the `Memory: ...` label in the final rendered frame, after the
+fix in `42f4602` moved the label above the memory graph's clear/braille passes. It does not
+replace the older 2026-09-11 captures; those remain as historical material.
+
+## Build identity
+
+| Field | Value |
+| --- | --- |
+| Commit | `42f460271a45907d4e571741de4e79642f9f9df8` |
+| Working tree at build time | clean (`git status --porcelain` = 0 paths) |
+| Build command | `cargo build --locked` |
+| Binary | `target/debug/grainx` |
+| Binary SHA-256 | `8572c7e189a5736733869c337482a6a348838c9148d44831ff1048f991f7bbcc` |
+| Toolchain | `rustc 1.94.1 (e408947bf 2026-03-25)` / `cargo 1.94.1 (29ea6fb6a 2026-03-24)` |
+| Renderer | `pyte 0.8.2` (throwaway venv; capture itself uses only the Python standard library) |
+| Host | macOS Apple Silicon (darwin arm64), UTC session date 2026-09-11 |
+
+## Captured artifacts
+
+| File | SHA-256 |
+| --- | --- |
+| `tui_capture_2026-09-11-memory.raw` | `153bc2be869554ac1850c65af18b91658a1fd025e04a3c271fff9b3d0f5a9a1e` |
+| `tui_capture_2026-09-11-memory.txt` | `4b83973388f19e59fbebf77e1660d128740d3fb61894f74632116bf5235a8af9` |
+
+## Render command
+
+~~~bash
+python3 -m venv /tmp/grainx-c-render-venv
+/tmp/grainx-c-render-venv/bin/pip install pyte==0.8.2
+/tmp/grainx-c-render-venv/bin/python demos/capture_tui.py \
+  target/debug/grainx \
+  demos/tui_capture_2026-09-11-memory.raw \
+  demos/tui_capture_2026-09-11-memory.txt \
+  5 110 50
+~~~
+
+Final-frame check (fails if the label was cleared):
+
+~~~bash
+python3 -c 'import sys; lines=open("demos/tui_capture_2026-09-11-memory.txt").read().splitlines(); sys.exit(0 if any("Memory:" in l for l in lines) else 1)'
+~~~
+
+Observed final frame (pyte, 110x50), row 18 is the label and rows 19-25 are the memory graph:
+
+~~~text
+Memory: 52.4% (12.6GB/24.0GB)
+Network I/O: RX 14.0 KB  TX 1.0 KB (last interval)
+~~~
+
+The network label keeps its per-interval byte-delta semantics; `KB/s` appears nowhere in the
+raw stream.
+
+## Regression test
+
+`tests/tui_memory_label.rs` checks, for several terminal sizes, that `DashboardLayout::memory_label_y()`
+is outside the memory graph rectangle (whose clear and braille passes rewrite every cell) and below
+the CPU graph clear pass. It fails on the pre-fix row:
+
+~~~bash
+cargo test --locked --test tui_memory_label
+~~~
+
+## Privacy
+
+Host snapshot fields present: OS name, kernel version, uptime, CPU core percentages, memory totals,
+disk label and sizes, top process names, PIDs, per-process CPU and memory sizes. A pattern scan of
+the new raw/txt captures found no home-directory paths, credentials, tokens, keys, emails, or IP
+addresses. Regenerate on a quiet host if a neutral process list is required.
+
+## Limitations
+
+- Values are one host and one instant, not benchmarks.
+- The `CPU Usage:` label still sits inside the CPU graph rectangle and is cleared by the same
+  class of pass; this pre-existing issue is out of scope for the memory-label fix.

demos/tui_capture_2026-09-11-memory.txt

@@ -0,0 +1,50 @@
+=== grainx System Monitor === Iteration: 2 ===
+
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+
+Memory: 52.4% (12.6GB/24.0GB)
+⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+Network I/O: RX 14.0 KB  TX 1.0 KB (last interval)
+⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+
+System: Darwin | Kernel: 25.6.0 | Uptime: 1h
+Network totals: RX:0.0MB TX:0.0MB
+CPU Cores: C0:43.7% C1:34.8% C2:25.6% C3:19.5% C4: 3.0% C5: 2.3% C6: 2.0% C7: 1.7%
+Disks: Mac:84.0%(460.4GB) Mac:84.0%(460.4GB)
+Top Processes (UP/DOWN to select, 'k' to kill, 'q' to quit):
+>   717 ScreenTimeAgent         0.0%    25056KB
+    852 commerce                0.0%    13664KB
+    703 CMFSyncAgent            0.0%     8576KB
+   3194 node                    0.0%   103520KB
+    915 spindump_agent          0.0%     4416KB
+    677 corespotlightd          0.0%   158992KB
+    653 CoreLocationAgent       0.0%    44832KB
+    634 audioaccessoryd         0.0%    29856KB
+    576 trustd                  0.0%        0KB
+    561 CategoriesService       0.0%        0KB
+
+
+Performance: 0.0FPS | 0.0ms | Adaptive: ON
+Config: grainx_advanced | Controls: q=quit, h=help, p=pause, a=adaptive, s=export

src/rendering.rs

@@ -68,6 +68,12 @@ impl DashboardLayout {
             footer_y,
         }
     }
+
+    /// Row for the memory label, kept just above `mem_rect` so the memory
+    /// graph's clear and braille passes can never overwrite it.
+    pub fn memory_label_y(&self) -> u16 {
+        self.mem_rect.y.saturating_sub(1)
+    }
 }
 
 pub struct AdvancedCanvas {

src/ui.rs

@@ -157,7 +157,7 @@ pub async fn draw_dashboard(
     canvas.set_color(cpu_color)?;
     canvas.draw_braille_line(&state.cpu_points, &ctx.layout.cpu_rect)?;
 
-    canvas.set_cursor(0, ctx.layout.mem_rect.y)?;
+    canvas.set_cursor(0, ctx.layout.memory_label_y())?;
     canvas.set_color(ctx.palette.label)?;
     canvas.draw_str(&format!(
         "Memory: {:.1}% ({:.1}GB/{:.1}GB)",

tests/tui_memory_label.rs

@@ -0,0 +1,24 @@
+use grainx::rendering::DashboardLayout;
+
+/// The memory label must be drawn outside the memory graph rectangle, which the
+/// clear pass and braille pass rewrite cell by cell, and below the CPU graph
+/// clear pass. Otherwise the label is erased before the frame reaches the screen.
+#[test]
+fn memory_label_row_is_not_cleared_by_graph_passes() {
+    for (width, height) in [(60, 20), (80, 24), (100, 32), (110, 50), (200, 80)] {
+        let layout = DashboardLayout::from_terminal_size(width, height);
+        let label_y = layout.memory_label_y();
+        let mem_top = layout.mem_rect.y;
+        let mem_bottom = mem_top + layout.mem_rect.height;
+        let cpu_bottom = layout.cpu_rect.y + layout.cpu_rect.height;
+
+        assert!(
+            label_y < mem_top,
+            "memory label row {label_y} overlaps memory graph rows {mem_top}..{mem_bottom} at {width}x{height}"
+        );
+        assert!(
+            label_y >= cpu_bottom,
+            "memory label row {label_y} is inside the CPU graph clear pass ending at {cpu_bottom} at {width}x{height}"
+        );
+    }
+}