feat(ruby): RSpec's described_class is the constant its example group names, so a spec's calls pin to the class under test (parser version bump)

CHANGELOG.md

@@ -13,6 +13,49 @@ not published here — see `docs/EVALS.md` for the instruments behind the headli
 
 ---
 
+## [Unreleased]
+
+
+### Added — RSpec's `described_class` is the class its example group names, so a spec's calls pin to the class under test (#338)
+
+`described_class` is how RSpec spells the class under test. Inside `RSpec.describe Calc do … end`,
+`described_class.m( 1 )` is `Calc.m( 1 )`. Its receiver is a bare identifier that no binding names, though, so every
+such call declined. A spec reached nothing through it, and `tested=`, `--seams` and `--test-gate` read the class under
+test as unreached by the spec written for it.
+
+The call now pins the way a written `Calc.m( 1 )` does (#267's constant-receiver arm). The rule is RSpec's own
+(rspec-core 3.13, `Metadata::ExampleGroupHash#described_class`): a group's described class is its first description
+argument, unless that is `nil` or a String, in which case it is the parent group's. So the innermost enclosing example
+group with a constant first argument answers. An example group is `describe` / `context` (and `feature`,
+`example_group` and the `x`- / `f`- spellings), called bare or on `RSpec`, with a block. A shared group
+(`shared_examples`, `shared_examples_for`, `shared_context`) stops the walk with no answer, because its body runs in
+whichever group includes it.
+
+Stated floors, each pinned by `test/rubydescribedclasscheck.sh`:
+- **(a)** A chained receiver (`described_class.new.m`) is untouched: #267's one-hop bound.
+- **(b)** A group with no constant (`describe "text"` at the top, `describe :sym`) names no class.
+- **(c)** A `describe` on any other receiver (`Docs.describe Calc do`) is not an RSpec example group.
+- **(d)** `subject`, the implicit `described_class.new`, is not modelled.
+- **(e)** A redefined `described_class` declines. A **method** of that name (any `:described_class` symbol, as in
+  `let( :described_class )`, or `def described_class`) declines every site in the file. A **local** of that name (an
+  assignment, `||=`, a multiple-assignment target, or a block or method parameter) declines the sites Ruby reads as
+  that local: after the binding in its own scope and in the blocks nested inside it, never in a sibling block, and
+  never across a `def`. The name is matched as a whole word, so `my_described_class = x` redefines nothing.
+- **(f)** A qualified describe is named by its final segment: `RSpec.describe Cask::Tab` reads as `Tab`. Where another
+  `Tab` defines the method too, the call splits between them. Where only the other `Tab` defines it, the call pins
+  there, unmarked. A written `Cask::Tab.m` behaves the same way.
+
+Measured with `--no-cache`, `--report` edge totals, `main` (3fcd515f) against this change:
+
+| Corpus | Edges |
+| --- | --- |
+| Rails app A | 26,649 → 26,755 (+106) |
+| Rails app B | 20,807 → 21,149 (+342) |
+| activerecord, activesupport, actionpack 8.1.3 `lib/`; this repo's `src/` | default map byte-identical |
+
+`kParserVer` → 125 (carried as 121 on the PR): `RawRef::recv` / `recvVar` change value for these call sites.
+The record layout is unchanged, so `kCacheVersion` stays 25.
+
 ## [0.6.5] — 2026-09-27
 
 

README.md

@@ -1977,9 +1977,9 @@ wrong, and it has. These are the results that say so, all in-tree, all published
 ### In the tests
 
 <details>
-<summary><b>650 gate scripts</b>, five contracts no unit test can hold, and the house rule: write the gate before the code it measures</summary> <!-- gatecount -->
+<summary><b>651 gate scripts</b>, five contracts no unit test can hold, and the house rule: write the gate before the code it measures</summary> <!-- gatecount -->
 
-`test/regression.sh` names **650 gate scripts** and is the authoritative list; <!-- gatecount -->
+`test/regression.sh` names **651 gate scripts** and is the authoritative list; <!-- gatecount -->
 `python3 test/pargates.py . ./build/ripwire -j 6` runs the same set in parallel. On top of them sit the
 contracts that do not fit a unit test: two runs byte-identical, warm output identical to cold, output
 that pipes clean through `xmllint --noout`, a sanitizer build with `-fno-sanitize-recover=all`, and a

docs/EVALS.md

@@ -21,7 +21,7 @@ section, and it is not an afterthought.
 | **Co-change / known-item evals** | `--eval`, `--eval-retrieval` (see `bench/ANSWERQUALITY.md`) | Whether the tool surfaces the other files a real historical commit touched; and known-item retrieval across four rankers. |
 | **Ensemble calibration harness** | `bench/ensemblecal/` | Whether `--ensemble`'s four evidence families are actually orthogonal, how often each fires, how stable each is across commits — and the preset ladder derived from that (§9). |
 | **Differential argv harness** | `test/argvdiffcheck.sh` | That a refactor changed *nothing observable*: two binaries, every argv vector, stdout + stderr + exit code byte-identical. |
-| **The gate suite** | `test/regression.sh`, `test/pargates.py` | 650 gate scripts plus the determinism, cache-transparency and golden contracts. <!-- gatecount --> |
+| **The gate suite** | `test/regression.sh`, `test/pargates.py` | 651 gate scripts plus the determinism, cache-transparency and golden contracts. <!-- gatecount --> |
 | **`--quality-delta`** | `src/quality.h` | Ten measured code-quality failure modes, reported only where a change made them worse. |
 
 ### The labeling protocol (why the held-out eval is allowed to disagree with the ranker)
@@ -5866,7 +5866,7 @@ copy here would be exactly the dialect divergence that gate exists to catch. Com
 tags, wrap, stable-order defaults), seven individually invoked standalone gates (`g1freshcheck`,
 `skillscan`, `htmlexport`, `compresscheck`, `handoffcheck`, `releaseinstallcheck`,
 `taskroutecheck`), and a single loop
-naming **650 gate scripts**, all of which exist on disk. <!-- gatecount -->
+naming **651 gate scripts**, all of which exist on disk. <!-- gatecount -->
 
 `python3 test/pargates.py . ./build/ripwire -j 6` runs the same scripts in parallel so a full
 verification fits in one sitting. It does not modify `regression.sh`.
@@ -6885,7 +6885,7 @@ Listed because the reason is more useful than the silence.
   shipped**. See `bench/locbench/anchorhop_calib.json`. The mention anchor's reproducible numbers are
   the ablations in §4.
 - **A single round gate-count.** Two in-tree numbers disagree (`test/pargates.py`'s docstring says
-  ~210; `test/argvdiffcheck.sh` says 200+), while the loop in `test/regression.sh` names 650. The <!-- gatecount -->
+  ~210; `test/argvdiffcheck.sh` says 200+), while the loop in `test/regression.sh` names 651. The <!-- gatecount -->
   loop is the authority; the stale docstrings are a known drift. Since 2026-09-10 the number is not
   written by hand anywhere: `docs/gatecount_build.py` derives it from the loop and rewrites every
   published site, `test/gatecountcheck.sh` fails if any of them drifts, and `test/manifestcheck.sh`

present/deck5_ripwire_build.js

@@ -1123,7 +1123,7 @@ function storyCards(s, { kick, head, stories, footText }){
   kicker(s, "// how it stays true", AMBER);
   title(s, "Proven, not promised");
   const cards = [
-    ["650 gate scripts", "the suite runs on every push — plus determinism, cache-transparency and golden contracts; the gate count itself is gated against the runner's own loop"], // gatecount
+    ["651 gate scripts", "the suite runs on every push — plus determinism, cache-transparency and golden contracts; the gate count itself is gated against the runner's own loop"], // gatecount
     ["byte-identical, always", "two runs over the same tree produce the same bytes; warm equals cold. Enforced in CI, twice — Release AND a plain flavour, because NDEBUG once blinded a whole class of checks"],
     ["differential refactoring", "a refactor must prove it changed nothing observable: two binaries, hundreds of argv vectors, stdout + stderr + exit codes byte-identical"],
     ["held-out labels, authored blind", "eval labels were written by reading source before the ranker ever ran on them — so the eval is allowed to say the ranker is wrong. It has."],
@@ -1147,7 +1147,7 @@ function storyCards(s, { kick, head, stories, footText }){
   title(s, "Claims you can trust, because we publish what failed", { size: 32 });
 
   card(s, MX, 1.72, 3.86, 1.72);
-  stat(s, "650", "gate scripts named by test/regression.sh — and the COUNT itself is gated against the runner's own loop, so it cannot go stale quietly", // gatecount
+  stat(s, "651", "gate scripts named by test/regression.sh — and the COUNT itself is gated against the runner's own loop, so it cannot go stale quietly", // gatecount
     MX+0.15, 1.86, 3.56, CYAN, { bsize: 42, bh: 0.66, lsize: 9.5 });
   card(s, 4.68, 1.72, 3.86, 1.72, CARD2);
   stat(s, "8", "registered NEGATIVES — changes built, gated green, measured against a band written before the code, and reverted rather than tuned",
@@ -1397,7 +1397,7 @@ function storyCards(s, { kick, head, stories, footText }){
     ["183 long flags · 34 slides",        "bash test/deckclaimcheck.sh"],
     ["every --flag named here exists",    "bash test/deckcheck.sh"],
     ["74.7% fewer element bytes",         "bash test/showcasecapturecheck.sh"],
-    ["650 gate scripts",                  "bash test/manifestcheck.sh"], // gatecount
+    ["651 gate scripts",                  "bash test/manifestcheck.sh"], // gatecount
     ["49 repos · 71 papers · 237 surveyed","bash test/readmedriftcheck.sh"],
     ["the ten moments, any row",          "ripwire . --callers=SYM | wc -c"],
     ["the head-to-head table",            "bench/headtohead/r4-2026-08-06/"],