Ψ-W1-T3 review remediation: soften the double-fire claim to unspecified-by-SDK, mark the unload mirror [verify — DAW], fix stale comment, drop redundant assertions, dedupe hook-partitioning comments, drop what-comment; file the action_registry test-seam deferral.

CLAUDE.md

@@ -181,7 +181,7 @@ Comments carry *why*, and context where non-obvious — never *what* the code al
   2. `rec->Register("gaccel", &accel)` — puts the action in the Actions list.
   3. `rec->Register("hookcommand", ...)` — receives every action fired; claim only your own id, return `false` otherwise.
   4. On unload (`rec == nullptr`), mirror-unregister everything with the same strings prefixed by `'-'`.
-- **Non-main sections use a different mechanism.** `gaccel_register_t` carries no section field — `command_id` + `gaccel` can only ever produce a Main-section action. To publish into another section (Media Explorer = 32063, MIDI editor = 32060, MIDI event list = 32061, MIDI inline = 32062), register a `custom_action_register_t{uniqueSectionId, idStr, name, extra}` under `"custom_action"`; it returns the command id, or **0 on failure** (e.g. a duplicate `idStr`) — which the caller must tolerate rather than half-register. `idStr` must be unique **across all sections**, so an action published into both Main and a non-main section needs a SECOND id string; the FOREVER-STABLE contract binds it identically from the moment it ships. `custom_action_register_t` has no `ACCEL`, so a non-main entry ships no default keybinding. Dispatch for these ids arrives through `"hookcommand2"` (`bool(KbdSectionInfo*, int command, int val, int val2, int relmode, HWND)`) — `"hookcommand"` runs for the main section only. The two hooks must partition the ids between them: claiming one command in both double-fires it. On unload, mirror with `"-custom_action"` and `"-hookcommand2"`.
+- **Non-main sections use a different mechanism.** `gaccel_register_t` carries no section field — `command_id` + `gaccel` can only ever produce a Main-section action. To publish into another section (Media Explorer = 32063, MIDI editor = 32060, MIDI event list = 32061, MIDI inline = 32062), register a `custom_action_register_t{uniqueSectionId, idStr, name, extra}` under `"custom_action"`; it returns the command id, or **0 on failure** (e.g. a duplicate `idStr`) — which the caller must tolerate rather than half-register. `idStr` must be unique **across all sections**, so an action published into both Main and a non-main section needs a SECOND id string; the FOREVER-STABLE contract binds it identically from the moment it ships. `custom_action_register_t` has no `ACCEL`, so a non-main entry ships no default keybinding. Dispatch for these ids arrives through `"hookcommand2"` (`bool(KbdSectionInfo*, int command, int val, int val2, int relmode, HWND)`) — `"hookcommand"` runs for the main section only. The two hooks must partition the ids between them; what happens when a command is claimed by both is unspecified by the SDK (`hookcommand2`'s doc says a `true` return prevents further hooks/actions from running, which is in tension with a clean double-fire either way), so nothing may rely on either outcome. On unload, mirror with `"-custom_action"` `[verify — DAW]` (the header confirms the `-` prefix for "most" registration types and spells out only `-pcmsrc` by name; `custom_action` itself is unconfirmed) and `"-hookcommand2"`.
 
 ## Product design docs
 

docs/PLAN.md

@@ -2412,7 +2412,10 @@ must not touch `main.cpp`; this track is why.
   (`custom_action` / `hookcommand2` / `-custom_action` mirror) — a deliverable of this
   track.
 - **DAW-verification obligation:** Daniel adds the action to the Media Explorer toolbar
-  and imports from it; also confirms the Main-section binding still fires.
+  and imports from it; also confirms the Main-section binding still fires. Also: unload,
+  reload, confirm no duplicate Media Explorer entry — the `-custom_action` unload mirror
+  is unconfirmed against the SDK header (root `CLAUDE.md` §"REAPER extension contract",
+  `[verify — DAW]`), and if unsupported the entry leaks across a reload.
 
 **Open questions.** `[verify]` re-verify `custom_action_register_t` and `hookcommand2`
 argument order/types against the SDK headers at implementation time (root `CLAUDE.md`

docs/TODO.md

@@ -445,3 +445,40 @@ today.
 bitmap and confirmed to place the stroke correctly, or it is redesigned to rasterize at
 physical rather than logical resolution once `IPlugViewContentScaleSupport` (or
 equivalent) makes scaling real.
+
+## `ingestHandleSectionCommand` has no unit test
+
+**Context (what shipped — Ψ-W1-T3, media-explorer-section).** The Media-Explorer
+import now dispatches through two hooks — `ingestHandleCommand` (Main,
+`"hookcommand"`) and `ingestHandleSectionCommand` (Media Explorer,
+`"hookcommand2"`). Both live in `ingest.cpp`, which compiles straight into the
+`reaper_reasampler` MODULE target.
+
+**The wart.** No `shell/` translation unit in this repo has a test target — every
+`<module>_tests` executable is a `core/` pure-module target. `ingestHandleSectionCommand`
+is a two-line command-id comparison; correctness here rests on code review, not CTest.
+Review verified this constraint is real and the deferral correct.
+
+**Intended fix.** Make `action_registry` a linkable library and give it the repo's
+first `shell/` test target, driven by a fake `reaper_plugin_info_t`. Its own header
+(`reaper_plugin.h:153-172`) shows `Register` is a plain member-function pointer on the
+struct, not a REAPER API pointer resolved through `REAPERAPI_LoadAPI` — a fake instance
+needs no live REAPER process to exercise `rec->Register(...)` calls. Once
+`action_registry` is test-covered, move the Media-Explorer section registration into it.
+
+**The constraint the fix MUST handle.** The extraction alone buys nothing:
+`action_registry` has no test target today either, so lifting `ingestHandleSectionCommand`
+into it without also standing up the test target just relocates the untested code. The
+same follow-up could collapse `ingest.cpp:466-472`'s hand-rolled `command_id`+`gaccel`
+pair onto `action_registry::registerAction`, which already does exactly that dance for
+the Q-W6 table.
+
+**Priority / risk.** Low / deferred. `ingestHandleSectionCommand` is a two-branch
+comparison, reviewed and correct at this scope; the gap is the missing test seam, not a
+known defect.
+
+**Done looks like.** `action_registry` is a linkable library with its own `shell/`-first
+CTest target driven by a fake `reaper_plugin_info_t`; the Media-Explorer section
+registration and `ingestHandleSectionCommand` move into it and gain unit coverage; and
+`ingest.cpp`'s own `command_id`+`gaccel` registration collapses onto
+`action_registry::registerAction` where the shapes match.

src/app/main.cpp

@@ -230,8 +230,8 @@ static bool OnHookCommand(int command, int /*flag*/)
 }
 
 // "hookcommand" covers the main section only, so actions we published into another
-// section arrive here instead. Claim ONLY those — every main-section id stays with
+// section arrive here instead. Partitioning contract: root `CLAUDE.md` §"REAPER
-// OnHookCommand, so no command can be claimed by both hooks.
+// extension contract".
 static bool OnHookCommand2(KbdSectionInfo* /*sec*/, int command, int /*val*/, int /*val2*/,
                            int /*relmode*/, HWND /*hwnd*/)
 {

src/shell/actions/ingest.cpp

@@ -479,7 +479,7 @@ void ingestRegisterActions(reaper_plugin_info_t* rec, ReaSamplerSession* session
     g_customImportMediaExplorer.uniqueSectionId = kSectionMediaExplorer;
     g_customImportMediaExplorer.idStr           = g_idImportMxStr.c_str();
     g_customImportMediaExplorer.name            = g_labelImportStr.c_str();
-    g_customImportMediaExplorer.extra           = nullptr;  // reserved
+    g_customImportMediaExplorer.extra           = nullptr;
     g_cmdImportMediaExplorerMx =
         rec->Register("custom_action", (void*)&g_customImportMediaExplorer);
     if (!g_cmdImportMediaExplorerMx)
@@ -496,8 +496,8 @@ bool ingestHandleCommand(int command) {
 
 bool ingestHandleSectionCommand(int command) {
     if (command == 0 || !g_session) return false;
-    // ONLY the Media Explorer id. The Main entry has its own distinct id and is claimed by
+    // ONLY the Media Explorer id — partitioning contract: root `CLAUDE.md`
-    // ingestHandleCommand off "hookcommand"; claiming it here too would double-fire it.
+    // §"REAPER extension contract".
     if (command == g_cmdImportMediaExplorerMx) { doImportFromMediaExplorer(); return true; }
     return false;
 }

tests/test_app_version.cpp

@@ -159,7 +159,7 @@ static void testMediaExplorerImportIdsAreDistinctAndChannelIsolated() {
     // The Media-Explorer import publishes into TWO action sections, and a custom_action
     // idStr must be unique across all sections — so the two entries carry two suffixes.
     // Both are FOREVER-STABLE per channel. Composed from the SHIPPED constants and checked
-    // against spelled-out literals, so a suffix edit in ingest.cpp fails here.
+    // against spelled-out literals, so a suffix edit in ingest.h fails here.
     const std::string mainId = channelCommandId(kIngestImportMediaExplorerId);
     const std::string mxId   = channelCommandId(kIngestImportMediaExplorerMxId);
 
@@ -174,22 +174,6 @@ static void testMediaExplorerImportIdsAreDistinctAndChannelIsolated() {
         CHECK(channelActionName("import Media Explorer file into selected track") ==
               "ReaSampler: import Media Explorer file into selected track");
     }
-
-    // Distinctness is what keeps the two dispatch hooks from both claiming one command:
-    // hookcommand owns the Main id, hookcommand2 owns the Media Explorer id. A suffix
-    // collapse would silently double-fire the import.
-    CHECK(mainId != mxId);
-
-    // Cross-channel isolation: this build's ids must NOT collide with the other channel's,
-    // or a beta install would rebind the stable keymap's entries. Asserted against the
-    // opposite channel's literals, which is the collision that would actually occur.
-    if (isBeta()) {
-        CHECK(mainId != "CEREBELLUM_REASAMPLER_INGEST_IMPORT_MEDIA_EXPLORER");
-        CHECK(mxId   != "CEREBELLUM_REASAMPLER_INGEST_IMPORT_MEDIA_EXPLORER_MX");
-    } else {
-        CHECK(mainId != "CEREBELLUM_REASAMPLER_BETA_INGEST_IMPORT_MEDIA_EXPLORER");
-        CHECK(mxId   != "CEREBELLUM_REASAMPLER_BETA_INGEST_IMPORT_MEDIA_EXPLORER_MX");
-    }
 }
 
 static void testStampClassifiesAsStampedOnOwnChannel() {