Skip empty damage work and index focus rules by pseudo-class

evidence/focus-rule-supply-20261006/README.md

@@ -0,0 +1,11 @@
+# Focus rule supply
+
+The existing RuleSet parser owns pseudo-class dependencies from every selector, including ancestor and nested selectors. Stylesheet.rules_map now indexes those declarations alongside target names. Focus/blur/focus-within acquisition selects indexed rules and deletes its scan of every rule for every changed scope. Actual dynamic selector checks, nested-scope target traversal, component/virtual DOM handling and cascade application remain unchanged. Candidate collection unions rule identities; cascade precedence still comes from the unchanged apply path.
+
+The rules_map reader first acquires rules, so a pending read/parse cannot serve an older index. Successful parse and reparse retire the same existing index; copies retain their normal source/parse lifetime. New pseudo-class keys cannot collide with native target keys (type, *, #id, .class). No new cache or registry.
+
+AST before: 249 native production, 467 test and 288 Toad production modules, zero omissions. RuleSet._post_parse is the dependency producer; Stylesheet.rules_map is the one index; App application focus, Widget focus and Screen changed focus-within scopes converge on _update_focus_dependencies. Existing matching/index readers were inspected. After native parser: 249 modules, zero omissions. External dynamic mutation is not proven absent by lexical AST; no new support for post-parse selector mutation is claimed. Three production lines replaced; index lifetime and all three focus consumers use the existing owner.
+
+Seven focused controls passed, including real mounted descendants/components across CSS read and reparse. One original matched sidebar App finished zero with empty stderr, 508 widgets/10 tabs, no provider. Right profile: same three focus updates, own declaration discovery 7.05ms -> .47ms and full method 19.03ms -> 11.22ms. Left full method 18.51ms -> 7.99ms. This is a single source headless observation. First-display medians 41.8/42.2ms versus 40.1/45.6ms, tails vary, paint was slower: no reliable overall frame or live speedup claim.
+
+RESULT.json binds original raw profiles/logs and source evidence. No new build, install, provider, public operation or repeated benchmark. The existing empty-damage pending_for checkpoint remains on this same PR, independently scoped.

evidence/focus-rule-supply-20261006/RESULT.json

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+{
+  "source": "6c5c0a055",
+  "controls": "7 passed in 1.09s",
+  "app_exit": 0,
+  "app_widgets": 508,
+  "app_tabs": 10,
+  "providers": 0,
+  "metrics": {
+    "before": {
+      "channels": {
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+        "own_seconds": 0.006711723,
+        "inclusive_seconds": 0.018510871
+      },
+      "thread": {
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+        "own_seconds": 0.007046747000000001,
+        "inclusive_seconds": 0.019031289
+      }
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+    "after": {
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+        "own_seconds": 0.00039156600000000004,
+        "inclusive_seconds": 0.007986836
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+        "calls": 3,
+        "own_seconds": 0.00046633400000000005,
+        "inclusive_seconds": 0.011223700000000001
+      }
+    }
+  },
+  "scope": "Single source App completed headless first-display check, not installed/live/terminal-pixel latency. Whole-frame medians and tails vary; no reliable overall speedup.",
+  "keepers": {
+    "evidence/focus-rule-supply-20261006/before.json": "66889e3b9ba8f9bcb5b50e9c5d9bdfd0114f0b83a43897a89287bf99891d77bf",
+    "evidence/focus-rule-supply-20261006/after.json": "554f279fe1d0248212feea3dcbf0d3f69bb0ac2276fcdbd635676319dfd9312e",
+    "evidence/focus-rule-supply-20261006/controls.log": "c928e2b325450f4fe53ea38feef281d6c7aed611956284bd9706a12f60e5c96a",
+    "/home/ts/.cache/agent-scratch/focus-rule-supply-20261006/app.stdout.log": "5247e1d6a489d95bcead12039f0c6af7ada02fe1327cdf371d94b8a1a02f3c2d",
+    "/home/ts/.cache/agent-scratch/focus-rule-supply-20261006/app.stderr.log": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+    "/home/ts/.cache/agent-scratch/focus-rule-supply-20261006/toggle-channels.pstats": "187497551c23b99916e7083098982a659112bdf7dcba9f7ea08ea63fff617fc6",
+    "/home/ts/.cache/agent-scratch/focus-rule-supply-20261006/toggle-thread.pstats": "762601eab880b54be284c0412aab7b5787a8b40bcc284a4b9af5962401140b89"
+  }
+}

evidence/focus-rule-supply-20261006/after.json

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+}