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

crates/ledger-gui/src/pages/journal.rs

@@ -60,41 +60,80 @@ fn attachment_name(b: &Books, id: u64) -> String {
         .unwrap_or_else(|| format!("attachment {id}"))
 }
 
-/// "Tax basis of FL-0001: personal-use conversion, contributor's basis
-/// $2,000.00 → tax basis $1,700.00". The tax basis is ledger-core's
-/// (`Asset::tax_basis`) for the event's rule and basis on the asset's
-/// book cost, which never changes once registered.
-fn tax_basis_text(b: &Books, asset_id: Option<u64>, p: &Value) -> String {
+/// "Tax basis of FL-0001: personal-use conversion, value $1,440.00,
+/// contributor's adjusted basis $1,688.40: §723 basis $1,688.40,
+/// depreciable basis $1,440.00, built-in loss $248.40". The figures are
+/// ledger-core's (`Asset::basis_figures`) for the event's facts on the
+/// asset; a pre-P3 `asset.tax_basis_set` (`legacy`: its rule by its old
+/// name, no value) reads the value as the book cost, as it was recorded.
+fn tax_basis_text(b: &Books, asset_id: Option<u64>, p: &Value, legacy: bool) -> String {
     let asset = asset_id.and_then(|id| b.ledger.get_asset(id));
     let name = match (asset, asset_id) {
         (Some(a), _) => a.tag.clone().unwrap_or_else(|| a.description.clone()),
         (None, Some(id)) => format!("asset {id}"),
         (None, None) => "an asset".to_string(),
     };
-    let rule = ledger_core::TaxBasisRule::parse(s(p, "rule"));
-    let contributor: Option<rust_decimal::Decimal> = p
-        .get("contributor_basis")
-        .and_then(|v| v.as_str())
-        .and_then(|v| v.parse().ok());
+    let dec = |k: &str| -> Option<rust_decimal::Decimal> {
+        p.get(k)
+            .and_then(|v| v.as_str())
+            .and_then(|v| v.parse().ok())
+    };
+    let rule = if legacy {
+        ledger_core::BasisRule::parse_legacy(s(p, "rule"))
+    } else {
+        ledger_core::BasisRule::parse(s(p, "rule"))
+    };
     let Some(rule) = rule else {
         return format!("Tax basis of {name} recorded");
     };
-    let tax = asset.and_then(|a| {
+    let adjusted = dec(if legacy {
+        "contributor_basis"
+    } else {
+        "contributor_adjusted_basis"
+    });
+    let fmv = (!legacy).then(|| dec("fmv_at_contribution")).flatten();
+    let method = p
+        .get("sec704c_method")
+        .and_then(|v| v.as_str())
+        .and_then(ledger_core::Sec704cMethod::parse);
+    let figures = asset.and_then(|a| {
         let mut a = a.clone();
-        a.tax = Some(ledger_core::TaxBasis {
+        a.basis = Some(ledger_core::AssetBasis {
             rule,
-            contributor_basis: contributor,
+            contributor_adjusted_basis: adjusted,
+            fmv_at_contribution: fmv,
+            sec704c_method: method,
+            source: None,
         });
-        a.tax_basis()
+        a.basis_figures().ok().flatten()
     });
     let mut text = format!("Tax basis of {name}: {}", super::assets::rule_words(rule));
-    if let Some(c) = contributor {
-        text.push_str(&format!(", contributor's basis {}", fmt::dollars(c)));
+    if let Some(v) = fmv {
+        text.push_str(&format!(", value {}", fmt::dollars(v)));
     }
-    match (tax, contributor.is_some()) {
-        (Some(t), true) => text.push_str(&format!(" → tax basis {}", fmt::dollars(t))),
-        (Some(t), false) => text.push_str(&format!(", tax basis {}", fmt::dollars(t))),
-        (None, _) => {}
+    if let Some(c) = adjusted {
+        text.push_str(&format!(
+            ", contributor's adjusted basis {}",
+            fmt::dollars(c)
+        ));
+    }
+    if let Some(f) = figures {
+        let mut parts = Vec::new();
+        if let Some(t) = f.tax_basis_723 {
+            parts.push(format!("§723 basis {}", fmt::dollars(t)));
+        }
+        parts.push(format!(
+            "depreciable basis {}",
+            fmt::dollars(f.depreciable_basis)
+        ));
+        if let Some(g) = f.built_in_gain_704c {
+            let (label, amount) = super::assets::gain_or_loss(g);
+            parts.push(format!("{} {}", label.to_lowercase(), fmt::dollars(amount)));
+        }
+        text.push_str(&format!(": {}", parts.join(", ")));
+    }
+    if let Some(m) = method {
+        text.push_str(&format!("; §704(c) method {}", m.key().replace('_', " ")));
     }
     text
 }
@@ -785,7 +824,12 @@ pub fn describe(b: &Books, line: &JournalLine) -> Option<Event> {
         }
         "asset.tax_basis_set" => ev(
             icon::SCALES,
-            tax_basis_text(b, asset_id, p),
+            tax_basis_text(b, asset_id, p, true),
+            asset_id.map(Route::Asset),
+        ),
+        "asset.basis_set" => ev(
+            icon::SCALES,
+            tax_basis_text(b, asset_id, p, false),
             asset_id.map(Route::Asset),
         ),
         "asset.corrected" => ev(