P3: assets' posted and scheduled depreciation, their bases, and the K-1 on the tax basis (defect 13, D-41)

Book value is cost less what the books posted; the schedule's figure is
apart. An asset's acquired date comes from its entry. Contributed
property keeps its section 723 carryover basis apart from its depreciable
basis (the lower of value and adjusted basis), with its 704(c) built-in
gain and method. The K-1 worksheet reports tax-basis capital (Form 1065
Item L) beside the book figures, leaving open what only the CPA knows.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01T3gXMVt7XJPi6ens1or9Dj

bookspec/examples/assets-book-value-is-what-the-books-carry.toml

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+# P3 defect 13, named regression 1 (list_assets_book_value_is_what_the_books_carry).
+id = "assets-book-value-is-what-the-books-carry"
+title = "Book value is cost less the depreciation posted, never the schedule's"
+rule = "An asset's carrying amount is its cost less the accumulated depreciation the books have recorded for it; what the depreciation schedule says is due through a date is a second figure, reported beside it, and their difference is depreciation not yet posted."
+status = "AUTHORITY"
+sources = [
+  "ASC 360-10-35-4 (cost less salvage allocated over the periods the asset serves)",
+  "wanderbooks docs/spec/rules.md B-24 (the register reconciles to the general ledger)",
+]
+tags = ["fixed-assets", "depreciation", "posted-vs-scheduled"]
+
+[setup]
+currency = "USD"
+fiscal_year_start = "01-01"
+basis = "accrual"
+rounding = "half-away-from-zero"
+
+[[setup.accounts]]
+code = "1500"
+name = "Equipment"
+type = "asset"
+
+[[setup.accounts]]
+code = "1510"
+name = "Accumulated Depreciation"
+type = "asset"
+
+[[setup.accounts]]
+code = "3000"
+name = "Capital"
+type = "equity"
+
+[[setup.accounts]]
+code = "6200"
+name = "Depreciation Expense"
+type = "expense"
+
+# A laptop contributed 2026-05-15 at 1,440.00, in service that day, 36
+# months, no salvage: 40.00 a month.
+[[setup.assets]]
+id = "laptop"
+description = "Laptop"
+cost = "1440.00"
+salvage = "0.00"
+life_months = 36
+in_service = "2026-05-15"
+method = "straight_line"
+cost_account = "1500"
+accumulated_account = "1510"
+expense_account = "6200"
+acquired_by = 1
+
+[[events]]
+date = "2026-05-15"
+description = "Laptop contributed"
+lines = [
+  { account = "1500", side = "debit", amount = "1440.00" },
+  { account = "3000", side = "credit", amount = "1440.00" },
+]
+
+# May's run, dated the month's last day: 40.00 x 17/31 = 21.9355 -> 21.94.
+[[events]]
+run_depreciation = { asset = "laptop", period = "2026-05" }
+
+[[expect]]
+query = "run"
+event = 2
+
+[expect.values]
+amount = "21.94"
+caught_up = "0.00"
+
+# Hand check: through May 20, 6 days of May, 40.00 x 6/31 = 7.7419 ->
+# 7.74 is due; the run is dated May 31, so nothing is posted yet, and the
+# book value is the cost (before P3 the tool called 1,432.26 book value).
+[[expect]]
+query = "register_row"
+asset = "laptop"
+as_of = "2026-05-20"
+values = { accumulated_posted = "0.00", accumulated_scheduled = "7.74", unposted = "7.74", book_value = "1440.00" }
+
+[[expect]]
+query = "register_row"
+asset = "laptop"
+as_of = "2026-05-31"
+values = { accumulated_posted = "21.94", accumulated_scheduled = "21.94", unposted = "0.00", book_value = "1418.06" }