Swift: computed-property reads create caller edges#1176
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Reading a Swift computed property (`obj.isReady`, `Store.canPublish`) runs its getter — behaviourally a call — but the paren-free syntax parsed as neither a call_expression (the call extractor) nor a capitalized Type.member value-read (the static-member pass). So a heavily-used gate property showed "No callers found", silently hiding real dependencies from callers / callees / impact / blast-radius. This is the frontier the docs call out for a Swift codebase (the crypto gates isWellFormed / canPublishBundle). - New internal-only referenceKind `property_read`, emitted by the Swift body walker for every navigation_expression value-read (instance and static receivers). Resolution maps it to a `calls` edge. - matchPropertyRead: strict, mirrors matchFunctionRef — binds to computed-`property` targets ONLY, same language family, same-file then a unique same-directory match, else drop. Swift stored properties extract as field/constant/variable (never `property`) and stdlib members aren't in the graph, so reads of `arr.count` / stored fields / Type.CONST / enum values resolve to nothing and drop — no new noise. A wrong "call" edge is worse than none. - The same-directory tier handles symlinked/mirrored source trees (a test target re-exposing app files) that put a second same-named property in a distant dir. Scoped to Swift end to end (extractor language check + sameLanguageFamily in the matcher), so no other language's resolution changes. Verified: full vitest suite green (2121 passed; the lone intermittent mcp-daemon timeout is pre-existing flake, passes in isolation). New test asserts a computed gate lists its readers while a same-shaped stored field does not. On the Auris crypto codebase, `callers isWellFormed` now returns receiveMessage and `callers canPublishBundle` returns registerSelf (both were "No callers found").
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Problem
Reading a Swift computed property —
enc.header.isWellFormed,Store.canPublishBundle— runs its getter, so it is behaviourally a call. But the paren-free syntax parsed as neither acall_expression(the call extractor) nor a capitalizedType.membervalue-read (the static-member pass). So a heavily-used gate property showed "No callers found", silently hiding real dependencies fromcallers/callees/impact/ blast-radius. On a real Swift codebase these are exactly the security choke points (a crypto header'sisWellFormed, an identity store'scanPublishBundle).Fix
property_readreference kind (sibling offunction_ref), emitted by the Swift body walker for everynavigation_expressionvalue-read (instance and static receivers). Resolution maps it to acallsedge.matchPropertyRead: strict, modelled onmatchFunctionRef— binds to computed-propertytargets only, same language family, same-file then a unique same-directory match, else drop. Swift stored properties extract asfield/constant/variable(neverproperty) and stdlib members aren't in the graph, soarr.count, stored-field reads,Type.CONST, and enum values resolve to nothing and drop — no new noise. A wrong "call" edge is worse than none.Scoped to Swift end-to-end (extractor language check +
sameLanguageFamilyin the matcher), so no other language's resolution changes. The eval harness has no Swift coverage, so this is neither exercised nor regressed by it; validated via the unit suite (which has Swift resolution tests) plus a real codebase.Tests
New resolution test: a computed-property gate lists both its readers as callers, while a same-shaped stored field of the same struct produces no bogus caller edge. Full suite green (2121 passed).