fix: sync live wall thickness preview

Issue: #234
User-Visible: yes

demo/smoke_wall_chain_thickness.mjs

@@ -7,7 +7,8 @@
  * no recorded thickness — the shape a mid-edit toolbar field used to produce —
  * and then reads three things that used to disagree: the committed partitions,
  * what the Thickness tool reports for the same stretch, and what a resumed
- * legacy draft carries.
+ * legacy draft carries. A missing live tail uses the current field; only an
+ * internal historical gap inherits the preceding segment.
  */
 import { launch, checkAll, finish } from './serve.mjs';
 const { page, browser } = await launch();
@@ -39,8 +40,8 @@ const res = await page.evaluate(async () => {
     [100 + 12 * g, 100 + 6 * g],
   ];
 
-  // Two recorded segments at 30 and 25 cm, then a third point whose thickness
-  // is missing: exactly what a field left mid-edit produced before #234.
+  // Two recorded segments at 30 and 25 cm, then a live third segment whose
+  // record does not exist yet. The current field is 30 cm.
   c._drawWallField = '30';
   await upd();
   out.fieldAcceptedThirty = c._drawWallCm === 30;
@@ -61,8 +62,8 @@ const res = await page.evaluate(async () => {
   out.storedThreeSegments = stored.length === 3;
   out.storedFirstThirty = stored[0] === 30;
   out.storedSecondTwentyFive = stored[1] === 25;
-  // The gap inherits the previous segment, never the global default.
-  out.gapInheritedPrevious = stored[2] === 25;
+  // A live missing tail uses the current field, not the previous segment.
+  out.liveTailUsesCurrentField = stored[2] === 30;
   out.nothingFellBackToFifteen = !stored.includes(15);
 
   // The Thickness tool reads the same value it stored: the mismatch between

docs/CHANGELOG.md

@@ -59,8 +59,10 @@
   edited between segments — used to be previewed at the drawn value and saved at
   15 cm, and the plan only revealed it later when the Thickness tool reported a
   number nobody had chosen. Preview, both writers and the Thickness highlight now
-  read one resolver, and a missing record inherits the previous segment of the
-  same chain ([#234](https://github.com/Matysh/houseplan-card/issues/234)).
+  read one resolver: a historical missing record inherits the previous segment,
+  while the live rubber-band uses the current field value and therefore no longer
+  changes thickness on click
+  ([#234](https://github.com/Matysh/houseplan-card/issues/234)).
 
 - Wall hatching no longer changes density with the space's grid scale. The same
   15 cm wall used to look different on plans with different `cell_cm` — from a

docs/CHANGELOG.ru.md

@@ -69,8 +69,9 @@
   отрезками, — показывался с нарисованной толщиной, а сохранялся с 15 см, и
   расхождение обнаруживалось позже: инструмент «Толщина» подсвечивал значение,
   которого никто не выбирал. Теперь превью, оба пути записи и подсветка читают
-  один резолвер, а пропуск наследует толщину предыдущего отрезка той же цепочки
-  ([#234](https://github.com/Matysh/houseplan-card/issues/234)).
+  один резолвер: старый пропуск наследует толщину предыдущего отрезка, а live
+  rubber-band использует текущее значение поля и больше не меняет толщину при
+  клике ([#234](https://github.com/Matysh/houseplan-card/issues/234)).
 
 - Плотность штриховки стен больше не зависит от масштаба пространства. Раньше
   одна и та же стена 15 см выглядела на планах с разным `cell_cm` по-разному —

docs/images/screenshots.json

@@ -1,7 +1,7 @@
 {
   "version": 1,
   "fixture": "synthetic-only",
-  "sourceFingerprint": "967bdb37e447ec29a88d82707f5ff957e576be72fbe801445c6cbdec970e43eb",
+  "sourceFingerprint": "2d8295e95a0721f11075dd0388ab4960c79b480ae199a381d3bbd1086e5e5b34",
   "captureScriptSha256": "34f2219790d46efd8250e7a1bd829cb8fc0b0547e1260635fefa52407551b41b",
   "command": "npm run build && node demo/docs/capture.mjs",
   "scenarios": {
@@ -13,7 +13,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "967bdb37e447ec29a88d82707f5ff957e576be72fbe801445c6cbdec970e43eb",
+      "sourceSha256": "2d8295e95a0721f11075dd0388ab4960c79b480ae199a381d3bbd1086e5e5b34",
       "imageSha256": "2885f96e348b15ab7c696e56e99bddcd9bb2ee94218a883e5a2155f45f5042aa"
     },
     "view-touch": {
@@ -24,7 +24,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "967bdb37e447ec29a88d82707f5ff957e576be72fbe801445c6cbdec970e43eb",
+      "sourceSha256": "2d8295e95a0721f11075dd0388ab4960c79b480ae199a381d3bbd1086e5e5b34",
       "imageSha256": "f62d8af3617c00a5e99511bd765980d2e27badf25047a1be34046b64195abe6c"
     },
     "space-create": {
@@ -35,7 +35,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "967bdb37e447ec29a88d82707f5ff957e576be72fbe801445c6cbdec970e43eb",
+      "sourceSha256": "2d8295e95a0721f11075dd0388ab4960c79b480ae199a381d3bbd1086e5e5b34",
       "imageSha256": "c33a7279165a4cec6fa6fadb6fd08cd967e082a17fe101ef442d27d36ae59b6b"
     },
     "room-contour-close": {
@@ -46,8 +46,8 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "967bdb37e447ec29a88d82707f5ff957e576be72fbe801445c6cbdec970e43eb",
-      "imageSha256": "4d63670c7bcca33da21a6cf17275786bed12e8422a50d02d4dabe59645f2cd82"
+      "sourceSha256": "2d8295e95a0721f11075dd0388ab4960c79b480ae199a381d3bbd1086e5e5b34",
+      "imageSha256": "3d22e1a2a96823e443833e40ea8b93747099b0fae1e9e19315d8789ae4604997"
     },
     "plan-context-tray": {
       "file": "05-plan-context-tray.png",
@@ -57,7 +57,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "967bdb37e447ec29a88d82707f5ff957e576be72fbe801445c6cbdec970e43eb",
+      "sourceSha256": "2d8295e95a0721f11075dd0388ab4960c79b480ae199a381d3bbd1086e5e5b34",
       "imageSha256": "a6c526fede11bc3503fd2384bd4a3f6afa008f481c5c47578f06cae6c81c6f9b"
     },
     "device-editor": {
@@ -68,7 +68,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "967bdb37e447ec29a88d82707f5ff957e576be72fbe801445c6cbdec970e43eb",
+      "sourceSha256": "2d8295e95a0721f11075dd0388ab4960c79b480ae199a381d3bbd1086e5e5b34",
       "imageSha256": "9585b59add4d35b5a6f028ce5b720ef1b77a3f8b19436d192cd1a0e6fc637264"
     },
     "device-display-preview": {
@@ -79,7 +79,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "967bdb37e447ec29a88d82707f5ff957e576be72fbe801445c6cbdec970e43eb",
+      "sourceSha256": "2d8295e95a0721f11075dd0388ab4960c79b480ae199a381d3bbd1086e5e5b34",
       "imageSha256": "cfc317da4628d079a116ff71311fbf06b1eb3b181928a5ea7ba888ab936a5e8b"
     },
     "background-editor": {
@@ -90,7 +90,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "967bdb37e447ec29a88d82707f5ff957e576be72fbe801445c6cbdec970e43eb",
+      "sourceSha256": "2d8295e95a0721f11075dd0388ab4960c79b480ae199a381d3bbd1086e5e5b34",
       "imageSha256": "d7cfe70551d9260169df8efd832e32ed7df99c7f60b55d1fd4a8322bd4c47175"
     },
     "room-card": {
@@ -101,7 +101,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "967bdb37e447ec29a88d82707f5ff957e576be72fbe801445c6cbdec970e43eb",
+      "sourceSha256": "2d8295e95a0721f11075dd0388ab4960c79b480ae199a381d3bbd1086e5e5b34",
       "imageSha256": "029a3e69ec647a8a370d99e6bb7f9225833c526739076022f6b52ba54bff30ea"
     },
     "device-info": {
@@ -112,7 +112,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "967bdb37e447ec29a88d82707f5ff957e576be72fbe801445c6cbdec970e43eb",
+      "sourceSha256": "2d8295e95a0721f11075dd0388ab4960c79b480ae199a381d3bbd1086e5e5b34",
       "imageSha256": "a06cbf83f09e2f67b3566d7c0b10e973db060c3d20786f26f74ada6a21937c3e"
     }
   }

scripts/mutation-gate.mjs

@@ -50,8 +50,22 @@ export const MUTANTS = [
       + 'that silently replaced 30 cm with 15 cm in the stored plan (#234)',
     patches: [{
       file: 'src/wall-face-graph.ts',
-      find: '    const cm = own ?? previous ?? fallbackTail;',
-      replace: '    const cm = own ?? fallbackTail;',
+      find: '    const inherited = previous ?? active ?? fallback;',
+      replace: '    const inherited = active ?? fallback;',
+    }],
+  },
+  {
+    id: 'chain-thickness-live-tail-inherits-previous',
+    guard: 'npx tsc -p tsconfig.test.json && node scripts/fix-test-build.mjs '
+      + '&& node --test --test-name-pattern="live rubber-band" '
+      + 'test/wall-face-graph.test.mjs',
+    because: 'the last missing thickness belongs to the live rubber-band, so a field change '
+      + 'between clicks must preview the value that the click will commit instead of inheriting '
+      + 'the preceding segment (#234)',
+    patches: [{
+      file: 'src/wall-face-graph.ts',
+      find: '    const liveTail = active ?? previous ?? fallback;',
+      replace: '    const liveTail = previous ?? active ?? fallback;',
     }],
   },
   {

src/wall-face-graph.ts

@@ -65,9 +65,11 @@ export function normalizeUnifiedWallTool(value: unknown): unknown {
  * the owner discovered it much later by hovering a wall. Two formulas for one
  * meaning always drift; there is exactly one here now.
  *
- * A missing record inherits the previous segment of the same chain, then the
- * toolbar field, then the default (owner's decision 2026-08-21): that is what
- * the person saw on screen while drawing, and a global default is not.
+ * A missing record inside a committed chain inherits the previous segment,
+ * then the toolbar field, then the default (owner's decision 2026-08-21).
+ * The final missing record is different: it is the live rubber-band, so the
+ * toolbar field must win before the previous segment. Otherwise changing the
+ * field between clicks previews the old thickness and commits the new one.
  *
  * Strictly positive is the validity boundary. The previous `wallChainSegments`
  * accepted a recorded zero, which cannot be drawn through the UI (1..100 cm,
@@ -89,12 +91,15 @@ export function chainSegmentCms(
   // ровно тем дублированием, которое задача и убирает. Невалидный default —
   // дефект вызывающего, поэтому он приводится к минимальной допустимой
   // толщине (1 см, docs/WALL-THICKNESS.md), а не к выдуманному значению.
-  const fallbackTail = valid(activeCm) ?? valid(defaultCm) ?? 1;
+  const active = valid(activeCm);
+  const fallback = valid(defaultCm) ?? 1;
   const out: number[] = [];
   let previous: number | null = null;
   for (let i = 0; i < count; i++) {
     const own = valid(recorded?.[i]);
-    const cm = own ?? previous ?? fallbackTail;
+    const inherited = previous ?? active ?? fallback;
+    const liveTail = active ?? previous ?? fallback;
+    const cm = own ?? (i === count - 1 ? liveTail : inherited);
     out.push(cm);
     previous = cm;
   }

test/wall-face-graph.test.mjs

@@ -55,17 +55,25 @@ test('chainSegmentCms fills a gap from the previous segment, then the field (#23
   // потеряна. Раньше запись давала 15, превью — 30; теперь ответ один.
   assert.deepEqual(chainSegmentCms(3, [30, 30], 30, 15), [30, 30, 30]);
   // Дырка в середине наследует предыдущий, а не следующий и не дефолт.
-  assert.deepEqual(chainSegmentCms(4, [30, undefined, 20], 12, 15), [30, 30, 20, 20]);
+  assert.deepEqual(chainSegmentCms(3, [30, undefined, 20], 12, 15), [30, 30, 20]);
   // Нет ни одной записи — текущее поле.
   assert.deepEqual(chainSegmentCms(2, [], 22, 15), [22, 22]);
   // Нет и поля — дефолт вызывающего.
   assert.deepEqual(chainSegmentCms(2, [], null, 15), [15, 15]);
 });
 
+test('chainSegmentCms gives the live rubber-band the current field value (#234)', () => {
+  // The last missing record is not historical damage: it is the segment under
+  // the cursor. A field change between clicks must be visible before commit.
+  assert.deepEqual(chainSegmentCms(2, [12], 24, 15), [12, 24]);
+  // With no active field, a missing tail remains a historical gap and inherits.
+  assert.deepEqual(chainSegmentCms(3, [30, undefined], null, 15), [30, 30, 30]);
+});
+
 test('chainSegmentCms treats only strictly positive records as valid (#234)', () => {
   // Прежняя wallChainSegments считала записанный 0 валидным; через UI ноль
   // недостижим (1..100 см), но в старом черновике лежать может.
-  assert.deepEqual(chainSegmentCms(3, [0, 30, 0], 25, 15), [25, 30, 30]);
+  assert.deepEqual(chainSegmentCms(3, [0, 30, 0], 25, 15), [25, 30, 25]);
   assert.deepEqual(chainSegmentCms(4, [NaN, -5, null, 'x'], 18, 15), [18, 18, 18, 18]);
   assert.deepEqual(chainSegmentCms(2, [Infinity, 40], 18, 15), [18, 40]);
 });