reference_conservation after #12221: if-arm argument is a conserved control; multiset control re-pinned

src/v2/compiler/reference_conservation.dag

@@ -120,6 +120,21 @@ fn reference_conservation_holds(report: ReferenceConservationReport) -> Bool {
   length(xs: report.dropped) == 0 && length(xs: report.unmeasured) == 0
 }
 
+// ACCEPTED IS A SEPARATE FACT FROM CONSERVED, AND A CONTROL THAT MEANS "THIS MODULE LOWERS" MUST ASK
+// BOTH. reference_conservation_holds admits refused atoms (a located refusal accounts for what it
+// covers), so on its own it cannot tell a module that lowered and kept every reference from one that
+// normalization REFUSED -- the refusal stands in for restored acceptance. A module is accepted when
+// nothing in it was refused and it conserved a nonzero population (a report that measured nothing
+// has not been accepted, only not rejected). Every control whose subject is "lowered, and ..." reads
+// these, not their parts, so no claim re-spells what acceptance is.
+fn reference_conservation_accepted(report: ReferenceConservationReport) -> Bool {
+  (report.refused == 0) && (report.conserved > 0)
+}
+
+fn reference_conservation_admitted(report: ReferenceConservationReport) -> Bool {
+  reference_conservation_holds(report: report) && reference_conservation_accepted(report: report)
+}
+
 // ---- the parse-side population -----------------------------------------------------------------
 
 // `items` counts the top-level items entered so far; `item_names` records each item's declaring

src/v2/compiler/reference_conservation_admission.dag

@@ -68,8 +68,9 @@ import extdeps.communication.medium { Lossless, Medium }
 // The shapes lowering is known to lose THAT A FIXTURE NEEDS TO EXCUSE, each pinned by its own
 // discriminating claim in v2.test.claim.namespace_xl0.reference_conservation. Closed on purpose: a
 // new shape is a new pinned claim first, then a row here, and a row enters only with the fixture
-// that consumes it (the block-later-statement and if-arm-argument drops are pinned there too, and
-// no admitted fixture's source contains them yet).
+// that consumes it (gunbc#12221 changed both shapes that were pinned there without a row here: the
+// if-arm argument is now conserved, and a block's later statement now REFUSES located, so both are
+// restated in that module -- as a conserved control and as a refused-not-accepted control).
 type KnownDropShape
   = NamedArgumentLabel
   | WhereRefinementPredicate

src/v2/test/claim/namespace_xl0/reference_conservation_test.dag

@@ -5,6 +5,8 @@ import v2.compiler.reference_conservation {
   ReferenceConservationReport,
   ReferenceConservationSubject,
   dag_declared_token_classes,
+  reference_conservation_accepted,
+  reference_conservation_admitted,
   reference_conservation_holds,
   reference_conservation_of_subject,
   reference_conservation_subject_of_read
@@ -20,8 +22,9 @@ import v2.std.live_tree { LiveTreeDisposition, SubstrateInputsOnly }
 import v2.std.logic { Bool }
 import v2.std.node { Symbol }
 import v2.std.text { String }
-import v2.std.integer { Int }
+import v2.std.integer { Int, integer_int_to_decimal_string }
 import extdeps.communication.medium { Lossless, Medium }
+import std.process { ProcessExit, exit_failure }
 
 data live_tree_disposition: LiveTreeDisposition = SubstrateInputsOnly
 
@@ -99,7 +102,7 @@ fn clean_control_report() -> ReferenceConservationReport {
 }
 
 test fn the_clean_control_conserves_every_authored_atom_holds() -> Bool {
-  reference_conservation_holds(report: clean_control_report())
+  reference_conservation_admitted(report: clean_control_report())
 }
 
 // The three numbers are separate and together account for the whole population: a check that
@@ -119,8 +122,18 @@ test fn the_clean_control_routes_the_test_marker_to_its_channel_holds() -> Bool
   clean_control_report().test_marker_channel == 1
 }
 
-// ---- drop 1: the second statement of a block ---------------------------------------------------
+// ---- former drop 1: the second statement of a block (now a located refusal, gunbc#12221) -------
 
+// MEASURED BOTH WAYS, AND THE SECOND WAY WAS HIDDEN. Before gunbc#12221 this body lowered and its
+// second statement reached no reference site: one DroppedReference. #12221 made a statement followed
+// by another REFUSE, located, so this module is no longer accepted. The old claim
+// (the_block_second_statement_is_reported_dropped_holds) kept passing because
+// reference_conservation_holds admits refused atoms: the refusal stood in for the drop. With
+// reference_conservation_accepted asked, it went red (seed-interpreted at 1204ef3922, fierce-gull-556).
+// Restated as what is true now: the module is refused, and neither accepted nor admitted. This is also
+// the shared mutation for every "lowered, and ..." control in this file: on a refusing report the
+// predicates they all ask are false, so each of them would be red. When a block's later statements
+// lower, this reds and is restated as a conserved control.
 data block_second_statement_source: String = "module v2.test.reference_conservation_block\n\nfn rc_block() -> Int { 1 \n 2 }\n"
 
 fn block_second_statement_subject() -> ReferenceConservationSubject {
@@ -131,15 +144,32 @@ fn block_second_statement_report() -> ReferenceConservationReport {
   conservation_report_of(subject: block_second_statement_subject())
 }
 
-test fn the_block_second_statement_is_reported_dropped_holds() -> Bool {
-  report_drop_count(report: block_second_statement_report(), wanted: ^dag_token_int_literal) == 1
+test fn a_block_with_a_second_statement_is_refused_not_accepted_holds() -> Bool {
+  let r = block_second_statement_report()
+  (r.refused > 0)
+    && !reference_conservation_accepted(report: r)
+    && !reference_conservation_admitted(report: r)
 }
 
-// ---- drop 2: a call argument inside an if-arm --------------------------------------------------
+// A REPORT, NOT A CLAIM: the block fixture's four numbers through the process exit, so a run shows
+// how the report counts a refused body.
+fn block_second_statement_numbers() -> ProcessExit {
+  let r = block_second_statement_report()
+  exit_failure(reason: "authored=" + integer_int_to_decimal_string(value: r.authored) + " conserved=" + integer_int_to_decimal_string(value: r.conserved) + " locus_erased=" + integer_int_to_decimal_string(value: r.locus_erased) + " refused=" + integer_int_to_decimal_string(value: r.refused) + " dropped=" + integer_int_to_decimal_string(value: length(xs: r.dropped)))
+}
+
+// ---- former drop 2: a call argument inside an if-arm (repaired by #12221) ---------------------
 
-// The argument's spelling is used NOWHERE else in its declaration, so the declaration-scoped pool
-// cannot account for it and the red names exactly it.
-data if_arm_call_argument_source: String = "module v2.test.reference_conservation_if_arm\n\nimport v2.std.logic { Bool }\n\nfn rc_callee(probe: Bool) -> Bool { probe }\n\ndata rc_arm_arg: Bool = true\n\nfn rc_if_arm(c: Bool) -> Bool { if c { rc_callee(probe: rc_arm_arg) } else { c } }\n"
+// MEASURED BOTH WAYS. Before gunbc#12221 the if-arm's call argument `rc_arm_arg` reached no reference
+// site and this check reported it as exactly one DroppedReference. After #12221 (if-arms lower
+// through the statement authority) the argument keeps its occurrence, and the pinned-drop claim went
+// red on origin/main 53828ae4b2 (fierce-gull-556, seed-interpreted). Restated, not deleted (DESIGN
+// section 4b(4)): it is now the permanent regression control that the if-arm argument is conserved.
+// The argument is POSITIONAL on purpose: a named argument's label is its own, separately rostered
+// drop (a_named_argument_label_is_reported_dropped_holds below), which would red this control for a
+// reason that is not the if-arm. The argument's spelling is used NOWHERE else in its declaration, so
+// the declaration-scoped pool cannot account for it: a regression drops it and names exactly it.
+data if_arm_call_argument_source: String = "module v2.test.reference_conservation_if_arm\n\nimport v2.std.logic { Bool }\n\nfn rc_callee(probe: Bool) -> Bool { probe }\n\ndata rc_arm_arg: Bool = true\n\nfn rc_if_arm(c: Bool) -> Bool { if c { rc_callee(rc_arm_arg) } else { c } }\n"
 
 fn if_arm_call_argument_subject() -> ReferenceConservationSubject {
   conservation_subject(id_tail: "if_arm_call_argument", source: if_arm_call_argument_source)
@@ -149,8 +179,9 @@ fn if_arm_call_argument_report() -> ReferenceConservationReport {
   conservation_report_of(subject: if_arm_call_argument_subject())
 }
 
-test fn the_if_arm_call_argument_is_reported_dropped_holds() -> Bool {
-  report_drop_count(report: if_arm_call_argument_report(), wanted: ^rc_arm_arg) == 1
+test fn the_if_arm_call_argument_is_conserved_holds() -> Bool {
+  let r = if_arm_call_argument_report()
+  reference_conservation_admitted(report: r) && report_drop_count(report: r, wanted: ^rc_arm_arg) == 0
 }
 
 // ---- former drop 3: a later operand of an operator chain (repaired by #12145) ------------------
@@ -171,7 +202,7 @@ fn infix_right_operand_report() -> ReferenceConservationReport {
 
 test fn the_infix_right_operand_is_conserved_holds() -> Bool {
   let r = infix_right_operand_report()
-  reference_conservation_holds(report: r) && report_drop_count(report: r, wanted: ^rc_rhs) == 0
+  reference_conservation_admitted(report: r) && report_drop_count(report: r, wanted: ^rc_rhs) == 0
 }
 
 // ---- a measured drop outside the brief: the named-argument label ------------------------------
@@ -192,7 +223,7 @@ fn named_argument_label_report() -> ReferenceConservationReport {
 
 test fn a_named_argument_label_is_reported_dropped_holds() -> Bool {
   let r = named_argument_label_report()
-  report_drop_count(report: r, wanted: ^rc_label) == 1 && length(xs: r.dropped) == 1
+  reference_conservation_accepted(report: r) && report_drop_count(report: r, wanted: ^rc_label) == 1 && length(xs: r.dropped) == 1
 }
 
 // ---- a list-literal call argument: conserved (was a module-wide refusal) ---------------------
@@ -218,21 +249,27 @@ fn list_literal_argument_report() -> ReferenceConservationReport {
 
 test fn a_list_literal_call_argument_conserves_every_element_holds() -> Bool {
   let r = list_literal_argument_report()
-  reference_conservation_holds(report: r)
-    && r.refused == 0
+  reference_conservation_admitted(report: r)
     && report_drop_count(report: r, wanted: ^rc_elsewhere) == 0
     && report_drop_count(report: r, wanted: ^rc_list_second) == 0
     && report_drop_count(report: r, wanted: ^rc_list_callee) == 0
 }
 
 // ---- the multiset control: a repeated spelling, one copy dropped -------------------------------
 
-// `rc_rep` is spelled three times in one declaration: as the parameter binder (rebuilt into an
-// edge label, so LocusErased against the pool's one label), as the first block statement (its
-// occurrence survives), and as the second block statement (dropped). The pool holds one copy and
-// the binder consumes it, so exactly ONE DroppedReference remains -- neither zero (a pool that
-// failed to consume) nor two (a pool that was never read).
-data repeated_spelling_source: String = "module v2.test.reference_conservation_repeat\n\nimport v2.std.logic { Bool }\n\nfn rc_repeat(rc_rep: Bool) -> Bool { rc_rep \n rc_rep }\n"
+// `rc_rep` is spelled three times in the declaration `rc_repeat`: as its parameter binder (rebuilt
+// into an edge label, so LocusErased against the pool's one label), as the named argument's LABEL at
+// the call (dropped: a call lowers its arguments positionally -- the rostered NamedArgumentLabel
+// shape), and as the argument's VALUE (its occurrence survives). The pool is declaration-scoped and
+// holds one copy, which the binder consumes, so exactly ONE DroppedReference remains -- neither zero
+// (a pool that failed to consume) nor two (a pool that was never read). `rc_callee`'s own `rc_rep`
+// binder and body use sit in a different declaration and cannot feed this pool.
+// RE-PINNED after gunbc#12221: the previous fixture dropped its repeated copy as the second of two
+// block statements (`{ rc_rep \n rc_rep }`), and #12221 made a statement followed by another refuse
+// located, so it no longer dropped one copy (red on origin/main 53828ae4b2). The multiset property is
+// the subject, not the statement shape, so the fixture now drops through the one shape still
+// rostered as a known drop.
+data repeated_spelling_source: String = "module v2.test.reference_conservation_repeat\n\nimport v2.std.logic { Bool }\n\nfn rc_callee(rc_rep: Bool) -> Bool { rc_rep }\n\nfn rc_repeat(rc_rep: Bool) -> Bool { rc_callee(rc_rep: rc_rep) }\n"
 
 fn repeated_spelling_subject() -> ReferenceConservationSubject {
   conservation_subject(id_tail: "repeated_spelling", source: repeated_spelling_source)
@@ -244,7 +281,7 @@ fn repeated_spelling_report() -> ReferenceConservationReport {
 
 test fn a_repeated_spelling_with_one_copy_dropped_is_exactly_one_row_holds() -> Bool {
   let r = repeated_spelling_report()
-  report_drop_count(report: r, wanted: ^rc_rep) == 1 && length(xs: r.dropped) == 1
+  reference_conservation_accepted(report: r) && report_drop_count(report: r, wanted: ^rc_rep) == 1 && length(xs: r.dropped) == 1
 }
 
 // ---- a measured drop found by admission: the where-refinement predicate -----------------------
@@ -262,7 +299,7 @@ fn where_refinement_predicate_subject() -> ReferenceConservationSubject {
 
 test fn the_where_refinement_predicate_is_reported_dropped_holds() -> Bool {
   let r = conservation_report_of(subject: where_refinement_predicate_subject())
-  report_drop_count(report: r, wanted: ^rc_pred) == 1 && length(xs: r.dropped) == 1
+  reference_conservation_accepted(report: r) && report_drop_count(report: r, wanted: ^rc_pred) == 1 && length(xs: r.dropped) == 1
 }
 
 // ---- measured drops found by admission: a later match arm, a statement-let binder -------------
@@ -274,7 +311,8 @@ test fn the_where_refinement_predicate_is_reported_dropped_holds() -> Bool {
 data match_later_arm_source: String = "module v2.test.reference_conservation_match\n\ntype RcT = RcA | RcB | RcC\n\ndata rc_first: Int = 1\n\ndata rc_second: Int = 2\n\ndata rc_third: Int = 3\n\nfn rc_match(t: RcT) -> Int {\n  match t {\n    RcA => rc_first\n    RcB => rc_second\n    RcC => rc_third\n  }\n}\n"
 
 test fn the_third_match_arm_is_reported_dropped_holds() -> Bool {
-  report_drops_identity(report: conservation_report_of(subject: match_later_arm_subject()), wanted: ^rc_third)
+  let r = conservation_report_of(subject: match_later_arm_subject())
+  reference_conservation_accepted(report: r) && report_drops_identity(report: r, wanted: ^rc_third)
 }
 
 // Found the same way through v2.test.claim.body_lowering.statement_let_bind: a statement-form let's
@@ -284,7 +322,7 @@ data statement_let_binder_source: String = "module v2.test.reference_conservatio
 
 test fn a_statement_let_binder_is_reported_dropped_holds() -> Bool {
   let r = conservation_report_of(subject: statement_let_binder_subject())
-  report_drop_count(report: r, wanted: ^rc_bound) == 1 && length(xs: r.dropped) == 1
+  reference_conservation_accepted(report: r) && report_drop_count(report: r, wanted: ^rc_bound) == 1 && length(xs: r.dropped) == 1
 }
 
 fn match_later_arm_subject() -> ReferenceConservationSubject {
@@ -309,7 +347,7 @@ fn anonymous_slots_subject() -> ReferenceConservationSubject {
 
 test fn two_anonymous_parameter_slots_are_conserved_by_minted_identity_holds() -> Bool {
   let r = conservation_report_of(subject: anonymous_slots_subject())
-  reference_conservation_holds(report: r)
+  reference_conservation_admitted(report: r)
     && report_drop_count(report: r, wanted: symbol_intern_lexeme(lexeme: "_")) == 0
     && r.authored > 0
 }