test: prove canonical directory test products

docs/build-system.md

@@ -2829,7 +2829,8 @@ and every component of the canonical import path. A selected command directory
 declares `package main` while retaining its complete canonical import identity.
 A source import of a command package from a
 different directory is rejected; the one same-directory exception is an
-external `main_test` variant's canonical import of its production action. Two
+external `main_test` variant's canonical import of its effective augmented
+test action. Two
 ordinary logical identities for one physical directory are rejected rather
 than compiled twice; section 11.16 records the deliberate exception for
 distinct expanded vendor routes that converge through symlinks.
@@ -2948,54 +2949,57 @@ supported manifest-free forms include `ww build DIR...`, `ww build DIR/...`,
 `ww test DIR...`, and `ww test DIR/...`, with overlapping direct and recursive
 roots. Test retains its existing `-run`, `-filter`, `-list`, `-timeout-ms`,
 `-j`, `-c`, and `-w` forms. `ww test -c -o test.bin DIR` names the result when
-the selected directory has one test variant; the coordinator rejects one output
-name for a multi-variant or recursive test request. Explicit `ww test FILE`
-retains its compatibility path.
+the request selects one canonical directory, including a directory with both
+same-package and external-package test sources. The coordinator rejects one
+output name only when it would fan out over multiple directory products.
+Explicit `ww test FILE` retains its compatibility path.
 
-The test coordinator still discovers requested directories, enumerates the
-test package names, selects variants, executes independent binaries, and emits
-captured results in byte-sorted package order. It no longer concatenates a
+The test coordinator still discovers requested directories, classifies the
+selected test package names, executes one binary per test-bearing canonical
+directory, and emits captured results in byte-sorted directory order. It no
+longer concatenates a
 generated production/test root, resolves imports, or starts one package graph
-per binary or directory. Instead it sends one ordered build request containing
-every selected directory/variant root to the Cstage or WWstage command. Its
-semantic selections are only the directory and selected variant/package
-identities; it also carries output destinations, coordinator-private completion
-paths, import search roots, and the optional command-scoped work-directory
-policy. The command owns source selection, package loading, compiler inputs,
-archive construction, generated-main construction, and linking for every
-package variant:
+per declared test package. Instead it sends one ordered build request containing
+one product descriptor per selected directory, with optional production,
+same-package, and external-package selectors, to the Cstage or WWstage command.
+It also carries output destinations, coordinator-private completion paths,
+import search roots, and the optional command-scoped work-directory policy.
+The command owns source selection, package loading, substitution, compiler
+inputs, archive construction, the single generated main, and linking:
 
 - The ordinary production action selects the directory's byte-sorted non-test
-  files. A no-test requested product uses this action directly, and every
-  ordinary, internal-test, or external-test import of that package reuses it.
+  files. A no-test request uses this action directly. Ordinary builds and
+  dependencies outside a tested closure continue to use it.
 - The internal production-plus-test variant selects the byte-sorted production
   files followed by byte-sorted matching `package p` test files. It is distinct
-  from production so its private production declarations and test declarations
-  remain isolated to that test product.
+  from production, exports declarations contributed by internal test files, and
+  replaces the ordinary action throughout the applicable tested closure.
 - When production sources establish `p`, the external variant selects only
   matching `package p_test` files, where `p` is the production declaration
   rather than an import-path leaf. A test-only directory may establish its own
-  one consistent test package name, matching pinned `go/build` classification.
-  A real source import of the production package uses its canonical import
-  path and is a direct edge to the same ordinary production action used by
-  ordinary products and transitive imports; there is no external-production
-  role or artifact.
+  `p`, `p_test`, or valid `p`/`p_test` pair, matching pinned `go/build`
+  classification. The external action's import of the package under test binds
+  to the augmented internal action when it exists. Importers affected by that
+  replacement are copied and rewired transitively; an ordinary and augmented
+  instance of one canonical package never coexist in the linked test closure.
 - Generated main is a separate package action whose owner-only generated unit
-  declares `package main` and imports exactly the selected variant and test
-  support. It consumes those direct `.wwi` files, emits its own `.wwi/.o/.a`,
-  and alone receives compiler `-T --entry`. Its target edge also receives the
-  compiler-private `--test-target-package <canonical-path>` binding. That
-  private canonical-path qualifier prevents a tested command declared `main`
-  from colliding with generated main; it is not user alias syntax.
+  declares `package main` and imports every applicable internal/external target
+  plus test support. It consumes those direct `.wwi` files, emits its own
+  `.wwi/.o/.a`, and alone receives compiler `-T --entry`. Repeated byte-sorted
+  `--test-target-package <canonical-path>` arguments identify the target set.
+  Those compiler-private canonical qualifiers prevent declared-name collisions;
+  they are not user alias syntax.
 
-The authoritative directory-action identity is the triple **(canonical
-filesystem directory, canonical ordinary import path, semantic variant)**.
-The semantic variants are production, internal production-plus-test, and
-external `_test`; generated main and the reserved test-support alias are
-explicit non-directory action classes. The declared package name is stored
-separately and is not part of canonical directory/path interning. Requested-root
-state, discovery role, product ordinal, output path, persistent artifact key,
-and discovery order never enter the triple.
+The coordinator groups one test product by canonical directory, but physical
+location is not a compiler/package identity. The authoritative action key uses
+the finalized canonical dotted import identity, semantic variant, role, and,
+for a copy made by recompile-for-test, the owning canonical directory product's
+stable test identity. The semantic variants are production,
+production-plus-same-package-test, external `_test`, directory generated main,
+and recompiled-for-test. The declared package name, local import binding,
+request spelling, path leaf, source filename, artifact basename, product
+ordinal, output path, and discovery order are presentation or source-location
+state and never substitute for that key.
 
 A literal directory root may enter the interner before its full import spelling
 is known. It is provisionally interned by canonical directory and variant, and
@@ -3059,19 +3063,19 @@ introduces a package registry.
 
 Artifact publication follows the semantic action instead of product order:
 production uses the full finalized ordinary identity, internal appends
-`-internal-test`, external appends `_test-external-test`, and their generated
-mains append `-main`. Generated package identities are likewise derived from
-the full variant identity, for example `__wwtestmain.a.foo.internal.main` and
-`__wwtestmain.b.foo_test.external.main`. Equivalent products therefore reuse an
-already-interned directory action and generated-main action and publish through
-the same persistent-workdir slots regardless of discovery or product order.
+`-internal-test`, external appends `_test-external-test`, and the one
+directory-owned generated main appends `-test-main`. Its package identity is
+`__wwtestmain.<canonical-directory-product-base>.main`, independent of either
+declared test name. Equivalent roots therefore converge on one directory
+product and reuse already interned actions and persistent-workdir slots
+regardless of discovery or request order.
 The narrow raw single-file compatibility path alone retains `__root`.
 
 A deterministic dependency-first traversal of the complete command union
 invokes the compiler, assembler, and in-driver deterministic archiver once per
 interned action. This is compile-time interning, not linker-argument
-deduplication. Each product is then linked separately from its generated-main
-or executable root archive and the complete reachable archive closure. The
+deduplication. Each canonical directory product is linked once from its single
+generated-main root archive and the complete reachable archive closure. The
 shared plan remains package-test-specific; it is not a generalized scheduler,
 action schema, cache, or protocol.
 
@@ -3095,15 +3099,19 @@ a rejected union build. After one successful union build, the completed test
 products share the coordinator's existing `-j` process bound; captured output
 is still emitted only in byte-sorted directory/package order.
 
-Every source-imported dependency is a production variant, so dependency
-`*_test.ww` files never enter the graph. Imports that occur only in selected
-test files add edges only to that internal or external variant. Each compiler
-unit contains only its action's owned source set, while its invocation receives
-only the byte-sorted direct dependency `.wwi` artifacts as separate inputs.
+Ordinary production loading never selects dependency `*_test.ww` files.
+Imports that occur only in selected test files add edges only to the applicable
+internal or external action. Recompile-for-test may create a product-scoped copy
+of an ordinary transitive importer, but that copy retains the importer's
+production source unit and changes only canonical dependency targets. Each
+compiler unit contains only its action's owned source set, while its invocation
+receives only the byte-sorted direct dependency `.wwi` artifacts as separate
+inputs.
 Variant compiles receive `--test-package`, which validates and retains private
 `@test` declarations as compiler-only export metadata without synthesizing an
-entry point. The distinct generated-main action consumes that metadata from its
-direct variant export and synthesizes the dispatcher with `-T`.
+entry point. The distinct directory generated-main action consumes that
+metadata from every direct target export and synthesizes one dispatcher with
+`-T`.
 
 The generated-main action, rather than the tested variant, owns the implicit
 direct test-runtime support edge. The command-scoped plan compiles the common
@@ -3125,22 +3133,23 @@ coexist only because the former is explicitly rebound to the compiler-only
 qualifier `__wwtest`. This is the sole role-based directory alias and cannot be
 created by a source import. The separate expanded-vendor-route exception in
 section 11.16 is canonical source-tree identity, not a role alias. All ordinary
-production actions, including an external test's colocated production
-dependency, use canonical directory identity and the global bidirectional
-import-path checks above. There is no role-based tolerance for duplicate
-ordinary import identities and no late product-closure ambiguity to resolve.
+and test actions use canonical action identity and the global bidirectional
+import-path checks above. External self-import substitution changes the target
+action, never the source spelling or file-local binding. There is no role-based
+tolerance for duplicate ordinary import identities and no late product-closure
+ambiguity to resolve.
 
-The selected internal/external variants and a production action reached by
-their imports or test-runtime closure are the sanctioned graph nodes that may
-share a physical directory. This also lets a toolchain package's own tests
-coexist with the production action required by the test runtime. An internal
-variant already defines those production symbols, so the colocated production
-archive is omitted from that product's final link while the production action's
-dependency archives remain in the closure. The external product includes the
-production archive. Variant-only archives are never linked into another
-product. All ordinary logical and physical package-identity collision checks
-remain unchanged; only distinct expanded vendor routes receive the section
-11.16 symlink-convergence exception.
+Production, internal, and external actions may select source from one physical
+directory, but the final directory test closure is strict: wherever the
+augmented internal action substitutes for production, every affected direct and
+transitive edge is rewired before tools. A closure containing both ordinary
+`p` and its augmented `ptest` is rejected rather than hidden by initialization
+or linker filtering. The external action therefore sees internal-test exports
+through `ptest`, and the one linked process owns exactly one package state.
+Variant-only archives never leak into an unrelated directory product. All
+ordinary logical and physical package-identity collision checks remain
+unchanged; only distinct expanded vendor routes receive the section 11.16
+symlink-convergence exception.
 
 Both stage linkers receive the generated-main archive first, followed by the
 complete reverse-topological reachable package-archive closure, runtime, and
@@ -3155,10 +3164,13 @@ one stable escape of the canonical discovery directory names the persistent
 command work directory. It contains neither a declared package leaf nor a
 product ordinal, so equivalent path spellings and reordered products select the
 same request state.
-Every `*_test.ww` package variant is built even when a file only
-declares helpers and contains no `@test`, so its package clause and imports are
-still checked by the shared loader. Every built variant is run, and a successful
-compiler-owned dispatcher with empty output is reported as `[no tests]`.
+Every selected `*_test.ww` package variant is built even when its files only
+declare helpers and contain no `@test`, so its package clause and imports are
+still checked; that is a real zero-test package and runs one empty combined
+harness. A directory with no selected test files instead follows the no-real-run
+path: validate/compile ordinary production as needed, publish status only, and
+create no support action, generated main, link, binary, result, or process. The
+coordinator alone emits its `[no tests]` report.
 
 Persistent workdirs keep a global driver/compiler/assembler/stamp identity and
 per-action committed units. When that global identity is stale, the command
@@ -3175,12 +3187,9 @@ stops as soon as a regenerated importer export is byte-identical. Stable
 semantic artifact keys make that behavior independent of which ordinary or
 test product first discovered the action.
 
-This ownership split follows the pinned Go 1.26.5 implementation cited in
-section 11.12: its loader reuses canonical cached package objects, its work
-builder interns actions by mode and package, and its test loader reuses ordinary
-production while constructing only the required internal, external, and
-generated-main variants. WW borrows that command-global ownership boundary
-without adding Go's build cache, import configuration format, or module system.
+The completed topology and its pinned Go 1.26.5 evidence are specified in
+section 11.22. WW borrows that command-global action boundary without adding
+Go's build cache, import-configuration format, or module system.
 
 ### 11.8 Implemented exact package-tool invocation slice
 
@@ -3389,7 +3398,8 @@ imports use their explicit compiler-owned bindings. Executable linking
 independently walks the full reachable package
 closure and passes archives, never interfaces. The same path handles an
 ordinary package, the production-plus-internal-test variant, the external test
-package and its reused production package, compiler-generated test main, and
+package and its effective production-or-augmented self dependency,
+compiler-generated directory test main, and
 the reserved test-support package. Persistent workdirs compare a newly emitted
 export with its committed predecessor before allowing a direct importer to
 reuse owner-identical artifacts, retaining correctness without a new cache
@@ -3411,8 +3421,9 @@ its non-`main` canonical identity in the unit, export, archive, compiler argv,
 and linker argv; the bootstrap self-rebuild independently proves the same rule
 for the real `w6a` and `w6l` command directories. A focused command-test row
 proves distinct production, internal, external, and generated-main actions,
-colocated external-production reuse, parser-only command markers, stage-equal
-unit/export/archive bytes, both test binaries' runtime behavior, and pre-tool
+colocated external-to-augmented substitution, parser-only command markers,
+stage-equal unit/export/archive bytes, the one combined test binary's runtime
+behavior, and pre-tool
 rejection when another directory tries to import the command.
 
 The exact-argv regression uses the real diamond
@@ -3424,9 +3435,9 @@ and byte-identical units, exports, archives, executables, and tool argument
 vectors across two clean
 Cstage builds and two clean WWstage builds. The existing directory-package
 variant regression checks separate production, internal, external, and
-generated-main actions, exact generated-main direct variant/support exports,
-canonical production reuse across ordinary and test products, and archive-only
-link closures. It also reverses equivalent product descriptors and compares
+directory-generated-main actions, exact generated-main direct target/support
+exports, canonical recompile-for-test substitution, and one archive-only link
+closure. It also reverses equivalent product descriptors and compares
 exact compiler and linker trace bytes, then changes a shared direct export in
 persistent workdirs to prove propagation through direct importers stops at the
 first byte-identical regenerated export. Both stages compile and run those
@@ -3661,9 +3672,10 @@ over 255 bytes.  They inspect the complete owner in units and exports, exact
 direct sorted/deduplicated `.wwi` compiler inputs, long mangled assembler
 symbols, complete archive-only link closures, runtime results, and independent
 Cstage/WWstage artifact bytes.  Two deep outside-root directories declaring
-the same leaf coexist under distinct reversible identities.  A long command
-package and its production, internal, external, and two generated-main actions
-remain distinct.  Logical and literal roots, dependency-first and root-first
+the same leaf coexist under distinct reversible identities. A long command
+package's internal, external, and one directory generated-main actions remain
+distinct while retaining its canonical package identity. Logical and literal
+roots, dependency-first and root-first
 discovery, equivalent and symlink spellings, reordered products, and warm
 requests reuse the same production action and persistent slot.  The persistent
 diamond observer also changes a shared dependency export, proves rebuilding of
@@ -3757,7 +3769,7 @@ lazily zero-extended `contextstate: []u8`.
 Products, load frames, and topological frames use typed dynamically allocated
 slices. `internal/wwpackage` continues to construct one union command for all
 selected directory-test groups, but now checks the complete
-`12 + 6*products + 2*includes` builder argument count before allocating or
+`12 + 9*products + 2*includes` builder argument count before allocating or
 starting the driver.
 
 All graph and product growth starts at capacity 8 and doubles until it covers
@@ -3819,30 +3831,26 @@ byte-identical export. Closing the chain at `p299 -> p000` produces the complete
 stage-identical 300-node cycle diagnostic with empty compiler, assembler, and
 linker traces.
 
-`dynamic_package_universe_crosses_former_boundary` first selects 309 package-test
-products through 257 directory spellings in one direct request per stage.
-Fifty-two real directories each produce ordinary production, internal
-production-plus-test, external `_test`, and two generated-main actions; the
-shared support closure brings that command-global universe to 270 actions. Two
-hundred five explicit symlink spellings of `p000` add distinct valid products
-and resolution contexts while reusing its one canonical internal action. The
-observer reverses product and variant order between stages, proves one compile
-per action, checks all 309 binaries exist, runs boundary products, validates
-variant-owned units, and compares every action artifact plus representative
-binaries byte-for-byte.
+`dynamic_package_universe_crosses_former_boundary` selects 257 canonical
+directory products in one direct request per stage. Fifty-two directories have
+combined same/external tests and each produces `ptest`, `pxtest`, and one
+directory `pmain`; 205 production-only directories take the no-test path. The
+shared support closure brings the command-global universe to exactly 370
+compile actions and 422 assembler invocations, with 52 generated dispatchers,
+links, binaries, and results. The 205 no-test products have only ordinary
+production actions and statuses: no support-owned target, main, link, binary,
+or result. The observer reverses all directory descriptors between stages,
+proves one compile per action, runs a boundary combined binary, validates
+variant-owned units and external self substitution, and compares representative
+action artifacts, normalized traces, and binaries byte-for-byte.
 
-The same observer then exercises the public `ww test <tree>/...` coordinator
-path. The generated tree has 257 real directories: the 52 test-bearing
-directories above plus 205 production-only directories. The coordinator forms
-and passes 309 products and 258 contexts (including support) in one driver
-request. Reusing the direct request's persistent semantic-action store preserves all 270
-existing actions and adds exactly 410 production/generated-main actions, for 680
-distinct actions. Both stages run every product, produce byte-identical ordered
-coordinator output and all 680 action artifacts, and perform no compilation on a
-second equivalent public request. It checks all 104 test-bearing result labels
-and all 205 no-test result labels, while a builder-boundary observer records
-exactly one invocation containing all 309 descriptors for each cold and warm
-public request. Existing focused observers continue to prove
+The same observer exercises the public `ww test <tree>/...` coordinator path
+against that persistent action store. The coordinator passes exactly 257
+directory descriptors in one driver request, prints 52 combined `ok` reports
+and 205 no-test `?` reports, and performs no new compilation. An unchanged warm
+request again invokes no compiler or assembler; the 52 real products follow the
+existing explicit-output relink convention while no-test products still create
+no linker work. Existing focused observers continue to prove
 dependency-first/root-first canonical reuse, root-only/combined artifact
 identity, exact reordered-product trace bytes, and request-shape-independent
 persistent action reuse.
@@ -4351,8 +4359,9 @@ selected test-only directory remains an unusable build root and fails. Build
 creates one production product per remaining directory. Test retains test-only
 directories and, after selection, constructs the already specified isolated
 production/no-test, internal production-plus-test, external `_test`, support,
-and generated-main actions. Pattern expansion does not create those variants
-and cannot make one variant visible to another.
+recompiled-for-test, and one directory-generated-main action. Pattern expansion
+does not create those actions; graph-owned substitution alone makes the
+augmented package visible through applicable external and transitive edges.
 
 Vendor selection remains distinct from vendor import resolution. Selecting a
 directory below `vendor`, literally or through an explicitly vendor-rooted
@@ -4592,14 +4601,14 @@ directory may establish one consistent package name from its test files, as in
 pinned `go/build`. External action identity remains the canonical production
 identity plus the existing external variant suffix where that production
 exists. Imports found only in internal or external test files belong only to
-that variant. Support and generated-main actions retain their isolated
+that action. Support and the directory generated-main retain isolated action
 identities and archive closures. A generated dispatcher privately binds its
-tested target through
-`--test-target-package <canonical-path>` so a command variant declared `main`
+tested targets through repeated, byte-sorted
+`--test-target-package <canonical-path>` arguments so a command variant declared `main`
 does not collide with the dispatcher's own synthesized `main`; this is
-compiler-generated wiring distinct from ordinary source aliases. Zero-test
-dispatchers mark their compiler-owned target/support metadata imports consumed.
-That private binding is installed or marked consumed only in the generated
+compiler-generated wiring distinct from ordinary source aliases. A real
+zero-test directory product marks all compiler-owned target/support metadata
+imports consumed. Those private bindings are installed or marked consumed only in the generated
 dispatcher's source section; an import from an earlier test-file section
 neither supplies nor satisfies it.
 
@@ -5117,14 +5126,15 @@ the reachable archive closure and runtime/native inputs; no `.wwi`, alias,
 blank spelling, or dispatcher sidecar appears.
 
 Production, production-plus-internal-test, external `_test`, test support, and
-generated main retain separate action identities. An internal product replaces
-the colocated production task with its combined variant and includes test-only
-blank edges/init declarations exactly once. An external product initializes
-ordinary production and its production dependencies before the external task.
-Support is an ordinary dependency task; generated main owns only the final
-dispatcher call and cannot duplicate a tested task. Test-file-only imports,
-runtime lets, and init functions never enter production. A blank import cannot
-bypass imported-`main` rejection, including through vendor expansion.
+directory generated main retain separate action identities. One canonical
+directory product replaces colocated production with `ptest` wherever internal
+tests augment it, rewires `pxtest` self-import and affected transitive importers
+to that action, and includes test-only blank edges/init declarations exactly
+once. Support is an ordinary dependency task; the one generated main owns only
+the final dispatcher call and cannot duplicate a tested task. Test-file-only
+imports, runtime lets, and init functions never enter production. A blank
+import cannot bypass imported-`main` rejection, including through vendor
+expansion.
 
 `.wwi` contains neither blank-only spelling, init declarations/bodies, hidden
 variable helpers, slice backing symbols, package tasks, nor dispatcher facts.
@@ -5139,7 +5149,7 @@ first regenerated byte-identical semantic export.
 
 The owner source voucher remains `<action>.unit.ww`; a linked product root also
 owns `<root>.init.unit.ww` for its dispatcher unit, `.init.s`, `.init.o`, and
-two-member archive. Current persistent formats are build 18 and test 17. Warm
+two-member archive. Current persistent formats are build 18 and test 19. Warm
 consumers select a dependency's staged `.wwi.new` or `.a.new` when that exact
 action changed in the same request. All action artifacts, init artifacts, tool
 identity copies, stamp, library/executable publications, and test statuses are
@@ -5184,9 +5194,10 @@ diamonds, independent lexical ties, aggregate and allocation initialization,
 multiple-cycle diagnostics, special-init rejection, test-variant isolation,
 canonical task/dispatcher/archive bytes, init-only invalidation, and warm
 invalid-init rollback across independent Cstage and WWstage roots. Direct and
-recursive test legs compare variant dispatcher/archive bytes and observable
-production-dependency order; exact task counts include support and generated
-main. Rejection rows compare complete normalized diagnostics and prove cold
+recursive test legs compare the one directory dispatcher/archive and observable
+dependency, `ptest`, `pxtest`, then `pmain` order; every production and
+dependency task runs exactly once. Exact task counts include support and the
+single generated main. Rejection rows compare complete normalized diagnostics and prove cold
 scratch absence. The observer also uses a repository-built `setrlimit` launcher
 to find one shared bounded-memory ceiling at which both drivers fail before a
 producer, and proves no-follow atomic rejection of dangling driver staging and
@@ -5305,7 +5316,7 @@ binary effect, or test execution.
 
 #### Persistence, rejection, and stage responsibility
 
-Persistent formats are build 18 and test 17 so a pre-slice workdir performs one
+Persistent formats are build 18 and test 19 so a pre-slice workdir performs one
 complete reachable-action refresh under the new membership contract. Thereafter
 an excluded-file add, removal, or content edit changes no unit voucher, `.wwi`,
 assembly, object, archive, dispatcher, test status, or reverse action. Existing
@@ -5340,9 +5351,242 @@ observers retain their broader ownership.
 Source-level `//go:build`/`+build` equivalents, arbitrary tags, cross-target
 selection, grouped/quoted/dot imports, modules, manifests, registries, and a
 programmable build language remain deliberately unsupported. Go's `UseAllFiles`
-escape is also not exposed. The separate remaining Go test-product topology
-divergence—one generated main for combined internal and external variants—is
-not hidden or changed by this slice.
+escape is also not exposed. Section 11.22 closes the formerly separate
+directory test-product topology divergence without changing these filename
+eligibility boundaries.
+
+### 11.22 Implemented one canonical directory package-test product
+
+`ww test` now owns one practical test product per canonical selected directory,
+not one product per declared test package. Production, augmented internal test,
+external test, support, recompiled dependency, and generated-main actions stay
+separate compilation units; only their execution/publication ownership is
+unified. This is the applicable Go 1.26.5 topology for WW's local, dotted,
+manifest-free package model.
+
+#### Pinned Go evidence and pre-fix divergence
+
+The reference is official Go 1.26.5 at commit
+`c19862e5f8415b4f24b189d065ed739517c548ba`:
+
+- `TestPackagesFor` defines one `pmain` test binary running `ptest` and optional
+  `pxtest`, with `ptest` equal to production plus same-package test files
+  ([`cmd/go/internal/load/test.go`, lines 85–101 and 175–226](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/internal/load/test.go#L85-L101)).
+- External self-import is recognized before the external package is formed and
+  is rebound to `ptest`, not ordinary `p`
+  ([lines 144–161 and 228–266](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/internal/load/test.go#L144-L161)).
+- One `pmain` receives both applicable targets, one sorted import set, and then
+  `recompileForTest` copy-on-write rewires every affected transitive importer
+  from ordinary production to the augmented package
+  ([lines 272–293, 342–376, and 421–490](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/internal/load/test.go#L272-L293)).
+- The generated source scans both target classes into one function set and one
+  `testing.MainStart`/`Run`
+  ([lines 595–638 and 790–860](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/internal/load/test.go#L595-L638)).
+- A directory with no selected test files takes the early ordinary-production
+  compile path and creates no test support, generated main, link, executable,
+  or subprocess; its print action reports `[no test files]`
+  ([`cmd/go/internal/test/test.go`, lines 1133–1170 and 1524–1557](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/internal/test/test.go#L1133-L1170)).
+- A real test package creates one generated source, one link action, and one
+  output-copy/install or run action, including `-c`/`-o`
+  ([lines 1200–1364](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/internal/test/test.go#L1200-L1364)).
+- Go's action cache distinguishes cloned package objects even when their import
+  paths match, compiler inputs come from the selected action's direct
+  dependencies, and the link closure selects one archive per import path
+  ([`cmd/go/internal/work/action.go`, lines 202–206, 437–447, and 628–658](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/internal/work/action.go#L202-L206),
+  [`exec.go`, lines 410–438 and 864–884](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/internal/work/exec.go#L410-L438)).
+- `go/build` classifies same-package and `_test` external files independently
+  and accepts directories containing only either class
+  ([`go/build/build.go`, lines 948–953, 1005–1036, and 1076–1082](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/go/build/build.go#L948-L953)).
+
+Official command testdata closes the observable cases. `test_empty.txt` lines
+3–24 and 30–53 accepts production-only, internal-only, external-only, combined,
+test-only internal, test-only external, and mixed test-only directories
+([source](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/testdata/script/test_empty.txt#L3-L24)).
+`vendor_test_issue11864.txt` lines 8–9 and 64–80 proves an external test can use
+an export declared only in an internal test source
+([source](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/testdata/script/vendor_test_issue11864.txt#L64-L80)).
+`list_test_imports.txt` lines 3–21 proves transitive rebuilding when a helper
+imports the package under test
+([source](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/testdata/script/list_test_imports.txt#L3-L21)).
+`toolexec.txt` lines 27–50 observes distinct `ptest`, `pxtest`, and `pmain`
+compiles but one main and linker call
+([source](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/testdata/script/toolexec.txt#L27-L50)).
+`test_no_tests.txt` lines 1–14 uses a panicking production initializer to prove
+that no-test reporting does not execute a test process
+([source](https://github.com/golang/go/blob/c19862e5f8415b4f24b189d065ed739517c548ba/src/cmd/go/testdata/script/test_no_tests.txt#L1-L14)).
+
+Before this slice WW constructed one generated main, link, binary, result, and
+report for each declared same/external test package. A combined directory ran
+two processes, initialized production state twice, hid internal-test exports
+from the external package, and made `-c -o` fail as a multi-product request.
+Even a directory with no selected tests manufactured support, a main, a link,
+and a temporary executable merely to print `[no tests]`. Test-only external
+directories were mislabeled, a valid mixed test-only directory was rejected,
+and a transitive importer was compiled against ordinary production.
+
+#### Final product and action topology
+
+For canonical directory product `P`, the action graph is:
+
+- `p`: ordinary production sources only;
+- `ptest`: production plus same-package selected `*_test.ww` sources;
+- `pxtest`: external-package selected `*_test.ww` sources only;
+- product-scoped recompiled actions: unchanged source units whose direct target
+  set was rewritten by the `p -> ptest` substitution;
+- support: one command-global production support action (or the reserved
+  `__wwtest` compiler binding when user `test` occupies that spelling);
+- `pmain`: one directory-owned generated-main action importing every applicable
+  target and support.
+
+The source shapes produce these reachable roots:
+
+| Directory shape | Test closure and externally visible product |
+| --- | --- |
+| production, no selected tests | ordinary `p`; no support/main/link/run/output/result |
+| production + internal | `ptest` + `pmain`; one binary/result |
+| production + external | unaugmented `p` + `pxtest` + `pmain`; one binary/result |
+| production + both | `ptest` + `pxtest -> ptest` + `pmain`; one binary/result |
+| test-only same package | `ptest` + `pmain`; one binary/result |
+| test-only external package | `pxtest` + `pmain`; one binary/result |
+| test-only same + external | `ptest` + `pxtest -> ptest` + `pmain`; one binary/result |
+
+A selected helper-only `*_test.ww` file is still a real test source: it is
+loaded and may yield an empty harness. The no-real-run branch is specifically
+the absence of selected test files after platform filtering. Ordinary
+`ww build` excludes test filenames before reading even their package clauses,
+so malformed test-only content and test-only imports cannot affect production.
+
+The coordinator in `internal/wwpackage/package.ww` classifies all selected
+files into one directory group. Classification is production-name-relative,
+so a legitimate production package literally named `foo_test` has external
+name `foo_test_test`; without production, a valid `p`/`p_test` pair is retained
+as same/external rather than blindly stripping every suffix. The private driver
+descriptor is an ordered directory record:
+
+```
+--ww-package-test KIND FAMILY PRODUCTION INTERNAL EXTERNAL DIR OUTPUT STATUS
+```
+
+Missing action selectors are `-`. One descriptor owns at most one output and
+one status. Canonically duplicate products and pairwise output/status/staging
+collisions reject before producer execution. Declared names and output stems do
+not identify products or actions.
+
+The Cstage and WWstage drivers first load and validate the ordinary production
+root. They form `ptest` and `pxtest` as separate source actions, bind external
+self-import to `ptest`, seed `p -> ptest`, and copy/rewrite the affected
+dependency closure. Both deduplicated dependency edges and every original
+file-local import binding target are rewritten through action identity. The
+strict closure validator rejects any leaked ordinary/augmented duplicate; no
+initialization or archive-order fallback can hide an incomplete substitution.
+
+`pmain` stores a checked, byte-sorted unique target action set. Its generated
+unit imports each target once plus support. The compiler argv repeats
+`--test-target-package` in that same order, followed by the exact byte-sorted
+direct `--import PATH WWI` set. Thus a combined shape has the essential form:
+
+```
+w6c --test-package ... -I PTEST.wwi -o PTEST.s PTEST.unit.ww
+w6c --test-package ... --import P PTEST.wwi ... -I PXTEST.wwi ...
+w6c -T --entry --test-support-module test \
+  --test-target-package P --test-target-package P_test \
+  --import P PTEST.wwi --import P_test PXTEST.wwi --import test TEST.wwi \
+  -I PMAIN.wwi -o PMAIN.s PMAIN.unit.ww
+```
+
+Actual arguments also contain action-owned init and dispatcher symbols. The
+assembler receives one source object per compiled action and exactly one
+`pmain.init.s -> pmain.init.o` dispatcher. Test target archives contain only
+their deterministic `pkg.o` member; the main archive contains `pkg.o` then
+`init.o`. Link argv is root plus reachable archives only:
+
+```
+w6l -o OUTPUT.new PMAIN.a [PXTEST.a] [PTEST-or-P.a] ... TEST.a libwwrt.a
+```
+
+No `.wwi`, source filename, standalone semantic object, or linker-order choice
+participates. Both native linkers already resolve archive members by symbols;
+they required no topology-specific change.
+
+#### Import, export, initialization, and execution ownership
+
+Default, explicit-alias, and blank imports remain file-local source
+occurrences. The package graph still uses one canonical edge per target and
+preserves every occurrence for usage and legality diagnostics. Substitution
+changes only the chosen canonical action. Consequently an external source
+continues to spell `import P`, but its direct compiler export input is
+`ptest.wwi`; an exported helper in an internal test source is ordinary augmented
+package export data and needs no special reader format. Per-owner `@test`
+metadata in `.wwi` remains sufficient. The writer/reader format did not change.
+
+`cmd/w6c/main.c`, `cmd/wcc/ww.h`, and `cmd/wcc/check.c`, with their self-hosted
+twins, changed singular generated-target state into a target set. Every target
+import is marked used, and every imported `@test` declaration receives its
+canonical target qualifier. The coordinator controls target order; the checker
+does not resolve directories. `wwdump` passes an empty target set on its
+non-test path.
+
+One dependency-first dispatcher is generated from the substituted closure.
+Each reachable canonical action contributes one initialization task; `pmain`
+is the sole entry package that calls the dispatcher. A combined directory
+therefore initializes dependencies, augmented production, external tests,
+support, and main exactly once in one process. Filtering and listing operate on
+the single deterministic enumeration containing both target sets; output has
+one accounting block and one directory report. `ww test -c -o OUTPUT DIR`
+publishes the one directory binary even when both target classes exist.
+
+#### Artifacts, persistence, invalidation, and rejection
+
+Semantic action artifacts remain separate: `.unit.ww`, `.wwi`, `.s`, `.o`, and
+`.a` for each production/test/recompiled/main/support action, plus main init
+unit/assembly/object. The directory product alone owns the binary, status, and
+result. Test persistent-work format is `19`; semantic package storage is format
+`3` and includes the product-scoped `for_test` identity for recompiled actions.
+There is still no cache, CAS, manifest, registry, database, or result cache.
+
+Warm reuse compares owner-unit bytes and exact direct export bytes. An internal
+helper body edit with stable `.wwi` rebuilds only `ptest` and relinks; external
+and reverse compilation stop. An external body-only edit rebuilds only
+`pxtest`. Adding or changing an exported internal helper changes `ptest.wwi`,
+then rebuilds exactly affected recompiled importers, `pxtest`, and `pmain`.
+Adding or removing a target class changes only the owning directory product and
+newly reachable actions. Request/root order and equivalent directory spelling
+do not change action bytes, target order, output, or reuse.
+
+Loader-owned source classification, import legality, canonical-product,
+duplicate-closure, cycle, command-kind, and publication-path errors reject
+before compiler, assembler, linker, support, or main work. Production failure
+is diagnosed once even though an augmented action would contain the same
+sources. Later compiler, assembler, generated-main, archive, link, staging, or
+commit failure remains one request-wide transaction: no sibling product runs,
+no status/result/binary or mixed generation is published, prior committed
+bytes remain unchanged, and every staged `.new` is discarded. Both drivers use
+checked dynamic allocation and transactional clone construction; allocation
+failure cannot publish a partial action or leave cleanup to traverse
+uninitialized storage.
+
+The native proof is primarily
+`directory_package_graph_variants`,
+`multi_directory_shared_package_plan`,
+`empty_and_invalid_package_classes`,
+`dynamic_package_universe_crosses_former_boundary`,
+`platform_filename_source_selection`,
+`vendor_directory_import_resolution`, and
+`test_variant_initialization`, with late transaction ownership in
+`sibling_test_variant_failures_are_isolated`. Together they compare
+cold/persistent Cstage and WWstage units, exports, assembly, objects, exact
+archive members, mains, binaries, diagnostics, runtime order, literal and
+normalized compiler/assembler/linker argv, both root orders in each stage,
+precise body/export and target-removal/re-addition invalidation, combined-graph
+allocation failure, repeated late internal/external/main/link rollback, and a
+complete work-directory sweep for staged residue.
+
+Deliberately unchanged or unsupported behavior includes the raw single-file
+compatibility path, WW's `[no tests]` presentation text, Go modules and build
+cache, network resolution, manifests, coverage/vet/fuzz/benchmark generation,
+source-level build expressions, quoted/grouped/dot imports, and targets other
+than the separately specified fixed `linux/amd64` filename selection. None is
+used to define canonical package or directory-product identity.
 
 ## 12. Candidate architectures and hard-gate decision
 

docs/spec.md

@@ -251,10 +251,12 @@ ImportName    = ident .
 ImportPath    = ident { "." ident } .
 ```
 
-- Every source file begins with a package clause. A directory of eligible
-  `.ww` files sharing one declared package name compiles as one package. The
-  declared name need not equal the directory name or the final component of its
-  canonical import identity.
+- Every source file begins with a package clause. Within one semantic source
+  action, eligible `.ww` files share one declared package name. Ordinary
+  production and same-package test sources use `p`; external test sources may
+  use the related `p_test`, and the actions remain separate even though one
+  canonical directory owns their test product. The declared name need not equal
+  the directory name or the final component of its canonical import identity.
 - Directory source eligibility uses Go 1.26.5 filename suffix semantics for
   WW's fixed `linux/amd64` target. In the basename stem before the first dot, a
   final `_test` token is ignored for platform matching. A final known OS or
@@ -286,10 +288,12 @@ ImportPath    = ident { "." ident } .
   initialization. Repeated blank occurrences and blank plus default/explicit
   named occurrences of one path are valid; every named occurrence remains
   independently subject to duplicate-binding and unused checks.
-  The package dependency graph is the sorted, deduplicated union of the real
-  imports in all eligible files. Occurrences retain their owning file and
-  position, but equal canonical targets create one graph edge/package action.
-  Self-import is rejected.
+  Each semantic action's package dependency graph is the sorted, deduplicated
+  union of real imports in that action's eligible source set. Occurrences retain
+  their owning file and position, but equal canonical targets create one graph
+  edge. Test-only occurrences never enter ordinary production. Self-import is
+  rejected, except that toolchain-owned external-test self wiring is rebound to
+  the effective augmented package action after ordinary per-site validation.
 - An executable package is one declared `package main` and containing a
   `fn main`; path and directory spelling do not classify commands. An ordinary
   import of a package declared `main` is rejected, except for the toolchain's
@@ -606,13 +610,21 @@ the program. Two placements, following the Go `foo` / `foo_test` model:
 ```
 
 Production, production-plus-white-box-test, external black-box-test, test
-support, and generated test main are distinct package actions. Before a test
-function runs, the generated test product initializes its exact reachable
-variant graph dependency-first and once per canonical action. A white-box
-variant replaces the colocated production task rather than initializing both;
-an external variant depends on ordinary production. Imports, runtime lets, and
-init declarations found only in `*_test.ww` never enter an ordinary production
-build.
+support, recompiled-for-test dependencies, and generated test main are distinct
+package actions. One canonical selected directory owns one test product and one
+generated main, which imports every applicable same-package and external target
+and produces one binary/result. The external action's import of the package
+under test binds to the augmented white-box action when it exists; affected
+transitive importers are copied and rewired so ordinary and augmented package
+state do not coexist in the linked closure.
+
+Before a test function runs, the one generated product initializes its exact
+effective graph dependency-first and once per canonical action. Imports,
+runtime lets, and init declarations found only in `*_test.ww` never enter an
+ordinary production build. Test-only same-package, external-package, and valid
+mixed directories are accepted from their selected test files. A directory
+with no selected test file validates ordinary production but creates no test
+support, generated main, link, binary, result, or process.
 
 ---
 

docs/test-system-v2.md

@@ -193,8 +193,9 @@ and nonempty-version-constant assertions.
 
 `ww test` delegates directory package requests to the native package
 coordinator. The coordinator owns request-pattern expansion, package grouping,
-same-package and external-package variant selection, filtering, result
-aggregation, and its internal temporary workspace. Test sources are exclusively
+same-package and external-package action selection, one canonical
+directory-owned product, filtering, result aggregation, and its internal
+temporary workspace. Test sources are exclusively
 `*_test.ww` (Go's `_test.go` contract): a line-leading `@test` declaration in
 any other source is rejected loudly — by both driver stages at directory
 enumeration and by the coordinator at source classification. A local spelling
@@ -204,8 +205,11 @@ directory prefix before the first wildcard. Recursive children beginning `.`
 or `_` and exact `testdata` subtrees are pruned; child directory symlinks are
 not followed. A wildcard cannot consume a non-terminal exact `vendor` element,
 while an explicitly vendor-rooted pattern remains legal. Every selected
-test-bearing directory becomes one package run, and selected source-bearing
-directories without tests report the usual `?` line. The coordinator first
+test-bearing directory becomes exactly one package run, binary, and result even
+when both internal and external actions exist. Selected source-bearing
+directories without selected test files report the usual `?` line after
+ordinary production validation, with no support, generated main, link, binary,
+result, or process. The coordinator first
 launches one driver plan for the complete command-global package/action union.
 After that shared build completes, `-j N` schedules up to N successful selected
 test binaries concurrently under `os.exec` start/poll supervision (no threads);
@@ -213,10 +217,11 @@ emission stays strictly in group order, so the byte stream is identical at
 every `-j` level, and `-j 1` — the default — matches the former sequential
 run loop exactly. Measured on the 31-package `lib/...` walk:
 7.0s sequential, 2.4s at `-j 4`. With `-c`, it publishes each exact
-`<package>.test` binary in the package directory; the first output owns the one
+`<package>.test` directory binary; the first output owns the one
 shared cold sepwork containing the command-global action universe. Those become
 caller-owned artifacts. `-c -o <name>`
-names that artifact instead of the fixed stem, for exactly one package:
+names that artifact instead of the fixed stem for exactly one directory,
+including a combined internal/external directory:
 the coordinator rejects a multi-package fan-out ("cannot use -o with
 multiple packages", Go's `go test -o` rule), and `-o` without `-c` is
 rejected at the driver ("needs -c for a package target") because a plain
@@ -256,8 +261,10 @@ archive/action ownership, one canonical direct edge for repeated occurrences,
 stage-equal diagnostics and binaries, and clean rejection state.
 The declared-name observer proves imports are file-scoped while dependency
 edges are the package-wide sorted union; command and
-production/internal/external/generated-main variants retain canonical action
-ownership; vendor expansion changes identity but not the effective qualifier;
+production/internal/external/directory-main actions retain canonical action
+ownership while one canonical directory owns their product; external
+self-imports bind the augmented internal action; vendor expansion changes
+identity but not the effective qualifier;
 compiler argv contains only direct `.wwi` inputs; and its named rejected
 actions leave neither committed nor staged action artifacts or a published
 binary. It also forces a request transaction to reject after dependency work
@@ -277,9 +284,15 @@ normalized compiler/assembler/linker argv, units, `.wwi`, assembly, objects,
 archives, generated-main archives, binaries, runtime/test output, direct and
 recursive behavior, reversed roots, ignored-edit reuse, selected private-change
 propagation, and request rollback after a dependency has staged and the root
-compiler fails. The existing bounded-memory package-initialization observer
-continues to own allocation-failure parity for the shared dynamically grown
-action universe.
+compiler fails. Wrong-target test files cannot add a target to the directory
+main or create one for an otherwise no-test directory. The bounded-memory
+package-initialization observer now pressures the combined directory topology
+itself: production, augmented internal test, external self-import, a transitive
+recompile-for-test clone, support, and the two-target generated main. Each stage
+searches its own bounded address-space ceiling, while the accepted failure must
+have the same `ww: out of memory` diagnostic, invoke no compiler, assembler, or
+linker, and leave an empty caller work directory with no output, status, or
+staging path.
 
 `test/sep/sepinit_test.ww` is the single focused package-initialization owner.
 It generates all source trees temporarily and runs independent cold/persistent
@@ -287,15 +300,18 @@ Cstage and WWstage legs. Its matrix covers blank-only reachability; dependency,
 diamond, and independent ready-task order; runtime call/allocation and aggregate
 package lets; multiple init declarations and invalid forms; direct/qualified
 init invisibility; initialization cycles and diagnostic order; command,
-internal-test, external-test, support, and generated-main ownership; canonical
+internal-test, external-test, support, and one directory-generated-main
+ownership; canonical
 task and dispatcher symbols; deterministic one- and two-member archives;
 `.wwi` exclusion; byte-identical artifacts/binaries; init-only invalidation;
 warm invalid-init rollback; direct/recursive variant equivalence; exact
-production, support, and generated-main task ordering; complete normalized
+production, support, ptest-before-pxtest-before-main task ordering, exactly-once
+package/dependency initialization in one dispatcher; complete normalized
 rejection diagnostics; dangling staging/rollback no-follow rejection; and
 checked compiler-output failure/non-regular-destination rollback; and
-bounded-memory allocation-failure parity under one shared ceiling supplied by
-the repository-built `sep-limitexec` helper.
+bounded-memory Cstage/WWstage allocation-failure parity across the complete
+combined package-test graph, under independently discovered ceilings supplied
+by the repository-built `sep-limitexec` helper.
 
 `ww build`, an explicit single-file `ww test -o <stem>`, and each successful
 directory-package `ww test -c` build publish `<stem>.sepwork` as a caller-owned
@@ -330,9 +346,11 @@ create false reuse or a mixed generation; a successful executable link still
 reruns when required. One workdir serves one invocation at a time and may hold
 the complete command-global action universe for all selected roots and isolated
 variants; semantic identity, rather than request shape, controls reuse. Both
-driver stages implement the identical contract. This is build staleness in the
+driver stages implement the identical contract. Test-mode persistent workdirs
+use format 19. This is build staleness in the
 Make/mk/Go sense, not a result cache:
-tests always run, and the byte-identity and bootstrap gates keep building on
+real directory test products always run, while no-selected-test directories do
+not create a process. The byte-identity and bootstrap gates keep building on
 fresh scratch. `make clean` reclaims every workdir under `out/`.
 
 On a package or tree target, `ww build/test -w DIR` forwards that exact caller

test/package/cases/pass/pass_test.ww

@@ -3,7 +3,7 @@ package pass_test;
 import test;
 
 @test fn alpha_pass() void = {
-	assert(test.current() == "pass_test.alpha_pass");
+	assert(test.current() == "pass.alpha_pass");
 };
 
 @test fn beta_skip() void = {

test/sep/sepinit_test.ww

@@ -736,7 +736,11 @@ fn rejectrow(td: str, label: str, src: str, expected: str) void = {
 	let td: str = testenv.fresh();
 	let tree: str = strings.concat(td, "/tree");
 	assert(os.mkdir(tree, 493) == 0);
-	let body: str = "package main;\n";
+	let target: str = strings.concat(tree, "/target");
+	let bridge: str = strings.concat(tree, "/bridge");
+	assert(os.mkdir(target, 493) == 0);
+	assert(os.mkdir(bridge, 493) == 0);
+	let body: str = "package target;\n";
 	let i: i32 = 0;
 	for (i < 600) {
 		let name: str = allocpkgname(i);
@@ -747,63 +751,98 @@ fn rejectrow(td: str, label: str, src: str, expected: str) void = {
 		body = strings.concat(body, "import _ ", name, ";\n");
 		i += 1;
 	};
-	body = strings.concat(body, "fn main() i32 = { return 0; };\n");
-	let src: str = strings.concat(td, "/main.ww");
-	testenv.writefile(src, body);
-	let wrapper: str = strings.concat(td, "/w6c-trace.sh");
+	body = strings.concat(body,
+		"export fn value() i32 = { return 41; };\n");
+	testenv.writefile(strings.concat(target, "/target.ww"), body);
+	testenv.writefile(strings.concat(target, "/same_test.ww"), strings.concat(
+		"package target;\n",
+		"export fn internal_helper() i32 = { return value(); };\n",
+		"@test fn internal_runs() void = { assert(value() == 41); };\n"));
+	testenv.writefile(strings.concat(bridge, "/bridge.ww"), strings.concat(
+		"package bridge;\nimport target;\n",
+		"export fn helper() i32 = { return target.internal_helper(); };\n"));
+	testenv.writefile(strings.concat(target, "/external_test.ww"),
+		strings.concat("package target_test;\nimport bridge;\nimport target;\n",
+		"@test fn external_runs() void = {\n",
+		" assert(target.internal_helper() == 41);\n",
+		" assert(bridge.helper() == 41);\n};\n"));
+	let wrapper: str = strings.concat(td, "/tool-trace.sh");
 	testenv.writeexecutable(wrapper, strings.concat("#!/bin/sh\n",
-		"printf x >> \"$WW_SEPINIT_W6C_TRACE\"\nexit 99\n"));
+		"printf x >> \"$WW_SEPINIT_TOOL_TRACE\"\nexit 99\n"));
 	let stages: []str = ["ww", "ww_ww"];
-	let compilers: []str = ["w6c", "w6c_ww"];
 	let launcher: str = testenv.driver("sep-limitexec");
-	let found: bool = false;
-	let last: str = "";
-	let limit: i64 = 2621440i64;
-	let li: i32 = 0;
-	// Both implementations must reject under the same address-space ceiling.
-	// Search a bounded same-limit ladder because loader mappings differ across
-	// supported hosts; the 600-action graph makes the driver-allocation window
-	// broad, while the compiler trace pins failure before the first tool.
-	for (limit <= 16777216i64 && !found) {
-		let limitstr: str = strconv.i64tos(limit, strconv.base.DEC);
-		let good: [2]bool;
-		let diags: [2]str;
-		i = 0;
-		for (i < stages.len) {
+	let accepted: [2]str;
+	let stagei: i32 = 0;
+	// Address-space layouts differ, so each implementation searches its own
+	// bounded ceiling. The accepted point must fail while constructing the
+	// combined p/ptest/pxtest/pmain and transitive-clone graph, before any tool.
+	for (stagei < stages.len) {
+		let found: bool = false;
+		let last: str = "";
+		let limit: i64 = 2621440i64;
+		let li: i32 = 0;
+		for (limit <= 33554432i64 && !found) {
 			let tag: str = allocpkgname(li);
-			let trace: str = strings.concat(td, "/alloc-", stages[i], "-",
+			let trace: str = strings.concat(td, "/alloc-", stages[stagei], "-",
 				tag, ".trace");
+			let work: str = strings.concat(td, "/alloc-work-", stages[stagei],
+				"-", tag);
+			let output: str = strings.concat(td, "/alloc-output-",
+				stages[stagei], "-", tag);
+			let status: str = strings.concat(td, "/alloc-status-",
+				stages[stagei], "-", tag);
 			testenv.writefile(trace, "");
-			let env: []str = compilertraceenv(wrapper,
-				testenv.driver(compilers[i]), trace);
-			let output: str = strings.concat(td, "/alloc-", stages[i], "-",
-				tag);
-			let av: []str = [launcher, limitstr, testenv.driver(stages[i]),
-				"build", "-I", tree, "-o", output, src];
+			assert(os.mkdir(work, 493) == 0);
+			let base: []str = os.getenvs();
+			let env: []str = alloc([], (base.len + 4): u64)!;
+			i = 0;
+			for (i < base.len) {
+				if (!strings.hasprefix(base[i], "WW_W6C=")
+					&& !strings.hasprefix(base[i], "WW_W6A=")
+					&& !strings.hasprefix(base[i], "WW_W6L=")
+					&& !strings.hasprefix(base[i],
+						"WW_SEPINIT_TOOL_TRACE=")) {
+					append(env, base[i]);
+				};
+				i += 1;
+			};
+			append(env, strings.concat("WW_W6C=", wrapper));
+			append(env, strings.concat("WW_W6A=", wrapper));
+			append(env, strings.concat("WW_W6L=", wrapper));
+			append(env, strings.concat("WW_SEPINIT_TOOL_TRACE=", trace));
+			let limitstr: str = strconv.i64tos(limit, strconv.base.DEC);
+			let av: []str = [launcher, limitstr, testenv.driver(stages[stagei]),
+				"test", "-c", "-w", work, "-I", tree,
+				"--ww-package-test", "test", "target", "target", "target",
+				"target_test", target, output, status, target];
 			let out: testenv.commandout;
-			runenv(td, strings.concat("allocation-", stages[i], "-", tag),
+			runenv(td, strings.concat("allocation-", stages[stagei], "-", tag),
 				av, env, &out);
 			last = strings.dup(out.stderr);
-			good[i] = exitcode(&out) == 1 && testenv.same(out.stderr,
-				"ww: out of memory\n")
-				&& testenv.readfile(trace).len == 0;
-			diags[i] = strings.dup(out.stderr);
-			if (testenv.exists(output) || testenv.exists(strings.concat(output,
-				".sepwork"))) {
+			if (testenv.listdir(work).len != 0
+				|| nofollowexists(output)
+				|| nofollowexists(strings.concat(output, ".new"))
+				|| nofollowexists(strings.concat(output, ".sepwork"))
+				|| nofollowexists(status)
+				|| nofollowexists(strings.concat(status, ".new"))) {
 				fail("allocation", "failed pressure leg published state");
 			};
-			i += 1;
-		};
-		if (good[0] && good[1]) {
-			if (!testenv.same(diags[0], diags[1])) {
-				fail("allocation", "C/WW allocation diagnostic mismatch");
+			if (exitcode(&out) == 1 && out.stdout.len == 0
+				&& testenv.same(out.stderr, "ww: out of memory\n")
+				&& testenv.readfile(trace).len == 0) {
+				accepted[stagei] = strings.dup(out.stderr);
+				found = true;
 			};
-			found = true;
+			testenv.clean(work);
+			limit += 131072i64;
+			li += 1;
 		};
-		limit += 131072i64;
-		li += 1;
+		if (!found) { fail("allocation", last); };
+		stagei += 1;
+	};
+	if (!testenv.same(accepted[0], accepted[1])) {
+		fail("allocation", "C/WW allocation diagnostic mismatch");
 	};
-	if (!found) { fail("allocation", last); };
 	testenv.clean(td);
 };
 
@@ -932,16 +971,12 @@ fn rejectrow(td: str, label: str, src: str, expected: str) void = {
 	let tags: []str = ["c", "ww"];
 	let reference: str = "";
 	let variantnames: []str = [
-		"widget-internal-test-main.init.unit.ww",
-		"widget-internal-test-main.init.s",
-		"widget-internal-test-main.init.o",
-		"widget-internal-test-main.a",
-		"widget_test-external-test-main.init.unit.ww",
-		"widget_test-external-test-main.init.s",
-		"widget_test-external-test-main.init.o",
-		"widget_test-external-test-main.a",
+		"widget-test-main.init.unit.ww",
+		"widget-test-main.init.s",
+		"widget-test-main.init.o",
+		"widget-test-main.a",
 	];
-	let variantrefs: []str = ["", "", "", "", "", "", "", ""];
+	let variantrefs: []str = ["", "", "", ""];
 	let i: i32 = 0;
 	for (i < 2) {
 		let work: str = strings.concat(td, "/test-work-", tags[i]);
@@ -967,61 +1002,45 @@ fn rejectrow(td: str, label: str, src: str, expected: str) void = {
 		let rr: i32 = testenv.pos(out.stdout, "<R>");
 		let ii: i32 = testenv.pos(out.stdout, "<I>");
 		let tt: i32 = testenv.pos(out.stdout, "<T>");
-		let tail: str = "";
-		if (tt >= 0) { tail = strings.sub(out.stdout, tt + 3, out.stdout.len); };
-		let de: i32 = testenv.pos(tail, "<D>");
-		let pe: i32 = testenv.pos(tail, "<P>");
-		let w: i32 = testenv.pos(tail, "<W>");
-		let e: i32 = testenv.pos(tail, "<E>");
-		let x: i32 = testenv.pos(tail, "<X>");
-		if (!(d >= 0 && d < q && q < rr && rr < p && p < ii && ii < tt
-			&& de >= 0 && de < pe && pe < w && w < e && e < x)) {
+		let w: i32 = testenv.pos(out.stdout, "<W>");
+		let e: i32 = testenv.pos(out.stdout, "<E>");
+		let x: i32 = testenv.pos(out.stdout, "<X>");
+		if (!(d >= 0 && d < q && q < rr && rr < p && p < ii && ii < w
+			&& w < e && e < tt && tt < x)) {
 			fail("variants", strings.concat("test init order: ", out.stdout));
 		};
 		if (testenv.occurrences(out.stdout, "<Q>") != 1
-			|| testenv.occurrences(out.stdout, "<D>") != 2
+			|| testenv.occurrences(out.stdout, "<D>") != 1
 			|| testenv.occurrences(out.stdout, "<R>") != 1
 			|| testenv.occurrences(out.stdout, "<W>") != 1
 			|| testenv.occurrences(out.stdout, "<I>") != 1
 			|| testenv.occurrences(out.stdout, "<E>") != 1
-			|| testenv.occurrences(out.stdout, "<P>") != 2) {
+			|| testenv.occurrences(out.stdout, "<P>") != 1) {
 			fail("variants", "variant initialization count");
 		};
-		let internal: str = testenv.readfile(strings.concat(work,
-			"/widget-internal-test-main.init.unit.ww"));
-		if (testenv.occurrences(internal,
+		let dispatcher: str = testenv.readfile(strings.concat(work,
+			"/widget-test-main.init.unit.ww"));
+		if (testenv.occurrences(dispatcher,
 			"__ww..pkg.p.testside.v0.r0.init") != 1
-			|| testenv.occurrences(internal,
+			|| testenv.occurrences(dispatcher,
 				"__ww..pkg.p.prodside.v0.r0.init") != 1
-			|| testenv.occurrences(internal,
+			|| testenv.occurrences(dispatcher,
 				"__ww..pkg.p.widget.v1.r0.init") != 1
-			|| testenv.occurrences(internal,
-				"__ww..pkg.p.test.v0.r0.init") != 1
-			|| testenv.occurrences(internal,
-				"//ww:init-call __ww..pkg.p.__wwtestmain.widget.internal.main.v3.r2.init") != 1
-			|| testenv.pos(internal, "__ww..pkg.p.test.v0.r0.init")
-				>= testenv.pos(internal,
-					"//ww:init-call __ww..pkg.p.__wwtestmain.widget.internal.main.v3.r2.init")
-			|| testenv.has(internal, "__ww..pkg.p.widget.v0.r0.init")) {
-			fail("variants", "internal variant dispatcher ownership");
-		};
-		let external: str = testenv.readfile(strings.concat(work,
-			"/widget_test-external-test-main.init.unit.ww"));
-		if (testenv.occurrences(external,
-			"__ww..pkg.p.widget.v0.r0.init") != 1
-			|| testenv.occurrences(external,
-				"__ww..pkg.p.prodside.v0.r0.init") != 1
-			|| testenv.occurrences(external,
+			|| testenv.occurrences(dispatcher,
 				"__ww..pkg.p.widget_test.v2.r0.init") != 1
-			|| testenv.occurrences(external,
+			|| testenv.occurrences(dispatcher,
 				"__ww..pkg.p.test.v0.r0.init") != 1
-			|| testenv.occurrences(external,
-				"//ww:init-call __ww..pkg.p.__wwtestmain.widget_test.external.main.v3.r2.init") != 1
-			|| testenv.pos(external, "__ww..pkg.p.test.v0.r0.init")
-				>= testenv.pos(external,
-					"//ww:init-call __ww..pkg.p.__wwtestmain.widget_test.external.main.v3.r2.init")
-			|| testenv.has(external, "testside")) {
-			fail("variants", "external variant dispatcher ownership");
+			|| testenv.occurrences(dispatcher,
+				"//ww:init-call __ww..pkg.p.__wwtestmain.widget.main.v3.r2.init") != 1
+			|| testenv.pos(dispatcher, "__ww..pkg.p.widget.v1.r0.init")
+				>= testenv.pos(dispatcher,
+					"__ww..pkg.p.widget_test.v2.r0.init")
+			|| testenv.pos(dispatcher,
+				"__ww..pkg.p.widget_test.v2.r0.init")
+				>= testenv.pos(dispatcher,
+					"//ww:init-call __ww..pkg.p.__wwtestmain.widget.main.v3.r2.init")
+			|| testenv.has(dispatcher, "__ww..pkg.p.widget.v0.r0.init")) {
+			fail("variants", "directory test dispatcher ownership");
 		};
 		let directstdout: str = strings.dup(out.stdout);
 		let recursivework: str = strings.concat(td, "/test-recursive-work-",
@@ -1100,7 +1119,7 @@ fn rejectrow(td: str, label: str, src: str, expected: str) void = {
 			av, env, tmo(), &out);
 		if (exitcode(&out) == 0
 			|| !testenv.has(out.stderr,
-				"ww: dependency cycle in initialization closure")
+				"ww: dependency cycle: p -> q -> r -> p")
 			|| testenv.readfile(trace).len != 0
 			|| testenv.listdir(work).len != 0) {
 			fail("test-cycle", out.stderr);