From f7ecc1e3734435675b92018df23ab610ee3cee1c Mon Sep 17 00:00:00 2001
From: dholms <dtholmgren@gmail.com>
Date: Tue, 11 Feb 2025 16:41:11 -0600
Subject: [PATCH] fix bug on right sibling proof & add some tests

---
 packages/repo/src/mst/mst.ts                |   5 +-
 packages/repo/tests/_keys.ts                | 156 ++++++++++++++++++++
 packages/repo/tests/covering-proofs.test.ts |  84 +++++++++++
 3 files changed, 244 insertions(+), 1 deletion(-)
 create mode 100644 packages/repo/tests/_keys.ts
 create mode 100644 packages/repo/tests/covering-proofs.test.ts

diff --git a/packages/repo/src/mst/mst.ts b/packages/repo/src/mst/mst.ts
index fc4a6117d8d..dab7d1f34eb 100644
--- a/packages/repo/src/mst/mst.ts
+++ b/packages/repo/src/mst/mst.ts
@@ -775,7 +775,10 @@ export class MST {
 
   async proofForRightSib(key: string): Promise<BlockMap> {
     const index = await this.findGtOrEqualLeafIndex(key)
-    const found = await this.atIndex(index)
+    let found = await this.atIndex(index)
+    if (!found) {
+      found = await this.atIndex(index - 1)
+    }
     let blocks: BlockMap
     if (!found) {
       // shouldn't ever hit, null case
diff --git a/packages/repo/tests/_keys.ts b/packages/repo/tests/_keys.ts
new file mode 100644
index 00000000000..2789c74cad4
--- /dev/null
+++ b/packages/repo/tests/_keys.ts
@@ -0,0 +1,156 @@
+export const A0 = 'A0/501344'
+export const A1 = 'A1/700567'
+export const A2 = 'A2/239654'
+export const A3 = 'A3/570745'
+export const A4 = 'A4/231700'
+export const A5 = 'A5/343219'
+export const B0 = 'B0/436099'
+export const B1 = 'B1/293486'
+export const B2 = 'B2/303249'
+export const B3 = 'B3/690557'
+export const B4 = 'B4/522003'
+export const B5 = 'B5/528640'
+export const C0 = 'C0/535043'
+export const C1 = 'C1/970596'
+export const C2 = 'C2/953910'
+export const C3 = 'C3/016643'
+export const C4 = 'C4/687126'
+export const C5 = 'C5/136391'
+export const D0 = 'D0/360671'
+export const D1 = 'D1/637976'
+export const D2 = 'D2/915466'
+export const D3 = 'D3/722333'
+export const D4 = 'D4/816246'
+export const D5 = 'D5/611412'
+export const E0 = 'E0/922708'
+export const E1 = 'E1/710014'
+export const E2 = 'E2/413113'
+export const E3 = 'E3/226890'
+export const E4 = 'E4/349347'
+export const E5 = 'E5/574759'
+export const F0 = 'F0/606463'
+export const F1 = 'F1/415452'
+export const F2 = 'F2/410478'
+export const F3 = 'F3/000172'
+export const F4 = 'F4/438093'
+export const F5 = 'F5/131765'
+export const G0 = 'G0/714257'
+export const G1 = 'G1/254594'
+export const G2 = 'G2/536869'
+export const G3 = 'G3/188348'
+export const G4 = 'G4/627086'
+export const G5 = 'G5/436727'
+export const H0 = 'H0/740256'
+export const H1 = 'H1/113887'
+export const H2 = 'H2/783135'
+export const H3 = 'H3/911996'
+export const H4 = 'H4/413212'
+export const H5 = 'H5/205035'
+export const I0 = 'I0/123247'
+export const I1 = 'I1/186251'
+export const I2 = 'I2/455864'
+export const I3 = 'I3/874267'
+export const I4 = 'I4/700662'
+export const I5 = 'I5/355687'
+export const J0 = 'J0/651505'
+export const J1 = 'J1/747356'
+export const J2 = 'J2/880562'
+export const J3 = 'J3/337247'
+export const J4 = 'J4/333302'
+export const J5 = 'J5/802321'
+export const K0 = 'K0/513509'
+export const K1 = 'K1/512199'
+export const K2 = 'K2/998695'
+export const K3 = 'K3/030175'
+export const K4 = 'K4/843537'
+export const K5 = 'K5/621841'
+export const L0 = 'L0/110539'
+export const L1 = 'L1/902119'
+export const L2 = 'L2/433601'
+export const L3 = 'L3/578589'
+export const L4 = 'L4/179159'
+export const L5 = 'L5/411430'
+export const M0 = 'M0/233209'
+export const M1 = 'M1/807305'
+export const M2 = 'M2/593452'
+export const M3 = 'M3/412948'
+export const M4 = 'M4/230935'
+export const M5 = 'M5/340624'
+export const N0 = 'N0/719700'
+export const N1 = 'N1/322330'
+export const N2 = 'N2/554905'
+export const N3 = 'N3/279414'
+export const N4 = 'N4/223549'
+export const N5 = 'N5/106430'
+export const O0 = 'O0/439753'
+export const O1 = 'O1/184934'
+export const O2 = 'O2/163117'
+export const O3 = 'O3/801944'
+export const O4 = 'O4/769058'
+export const O5 = 'O5/682431'
+export const P0 = 'P0/312289'
+export const P1 = 'P1/708697'
+export const P2 = 'P2/085809'
+export const P3 = 'P3/664012'
+export const P4 = 'P4/515888'
+export const P5 = 'P5/973781'
+export const Q0 = 'Q0/322861'
+export const Q1 = 'Q1/010908'
+export const Q2 = 'Q2/786194'
+export const Q3 = 'Q3/614951'
+export const Q4 = 'Q4/915803'
+export const Q5 = 'Q5/475163'
+export const R0 = 'R0/874630'
+export const R1 = 'R1/430647'
+export const R2 = 'R2/767178'
+export const R3 = 'R3/943288'
+export const R4 = 'R4/582084'
+export const R5 = 'R5/501429'
+export const S0 = 'S0/275258'
+export const S1 = 'S1/739500'
+export const S2 = 'S2/449586'
+export const S3 = 'S3/891280'
+export const S4 = 'S4/156946'
+export const S5 = 'S5/027482'
+export const T0 = 'T0/515259'
+export const T1 = 'T1/898487'
+export const T2 = 'T2/102538'
+export const T3 = 'T3/666778'
+export const T4 = 'T4/976512'
+export const T5 = 'T5/843268'
+export const U0 = 'U0/948132'
+export const U1 = 'U1/844531'
+export const U2 = 'U2/428499'
+export const U3 = 'U3/676721'
+export const U4 = 'U4/746122'
+export const U5 = 'U5/758627'
+export const V0 = 'V0/625208'
+export const V1 = 'V1/894664'
+export const V2 = 'V2/449156'
+export const V3 = 'V3/800489'
+export const V4 = 'V4/715514'
+export const V5 = 'V5/777528'
+export const W0 = 'W0/543856'
+export const W1 = 'W1/610464'
+export const W2 = 'W2/735768'
+export const W3 = 'W3/268620'
+export const W4 = 'W4/542722'
+export const W5 = 'W5/515212'
+export const X0 = 'X0/358710'
+export const X1 = 'X1/930435'
+export const X2 = 'X2/229496'
+export const X3 = 'X3/642411'
+export const X4 = 'X4/792973'
+export const X5 = 'X5/997958'
+export const Y0 = 'Y0/224673'
+export const Y1 = 'Y1/383255'
+export const Y2 = 'Y2/036710'
+export const Y3 = 'Y3/941868'
+export const Y4 = 'Y4/989940'
+export const Y5 = 'Y5/885038'
+export const Z0 = 'Z0/660512'
+export const Z1 = 'Z1/946648'
+export const Z2 = 'Z2/470347'
+export const Z3 = 'Z3/744138'
+export const Z4 = 'Z4/679676'
+export const Z5 = 'Z5/904085'
diff --git a/packages/repo/tests/covering-proofs.test.ts b/packages/repo/tests/covering-proofs.test.ts
new file mode 100644
index 00000000000..b0a6d516c9c
--- /dev/null
+++ b/packages/repo/tests/covering-proofs.test.ts
@@ -0,0 +1,84 @@
+import { CID } from 'multiformats'
+import { MST } from '../src/mst'
+import { MemoryBlockstore } from '../src/storage'
+import * as k from './_keys'
+
+describe('covering proofs', () => {
+  /**
+   *
+   *                *                                  *
+   *       _________|________                      ____|____
+   *       |   |    |    |   |                    |    |    |
+   *       *   b  __*__  f   *       ->         __*__  d  __*__
+   *       |     |     |     |                 |  |  |   |  |  |
+   *       a     c     e     g                 *  b  *   *  f  *
+   *                                           |     |   |     |
+   *                                           a     c   e     g
+   *
+   *
+   *
+   */
+  it('two deep split ', async () => {
+    const storage = new MemoryBlockstore()
+    const cid = CID.parse(
+      'bafyreie5cvv4h45feadgeuwhbcutmh6t2ceseocckahdoe6uat64zmz454',
+    )
+
+    let mst = await MST.create(storage)
+    mst = await mst.add(k.A0, cid)
+    mst = await mst.add(k.B1, cid)
+    mst = await mst.add(k.C0, cid)
+    mst = await mst.add(k.E0, cid)
+    mst = await mst.add(k.F1, cid)
+    mst = await mst.add(k.G0, cid)
+
+    const pointerBeforeOp = await mst.getPointer()
+
+    mst = await mst.add(k.D2, cid)
+    const proof = await mst.getCoveringProof(k.D2)
+
+    const proofStorage = new MemoryBlockstore(proof)
+    let proofMst = await MST.load(proofStorage, await mst.getPointer())
+    proofMst = await proofMst.delete(k.D2)
+    const pointerAfterInvert = await proofMst.getPointer()
+    expect(pointerAfterInvert.equals(pointerBeforeOp)).toBe(true)
+  })
+
+  /**
+   *
+   *                *                               *
+   *           _____|_____                      ____|____
+   *           |  |   |  |                      |   |   |
+   *           a  b   d  e       ->             *   c   *
+   *                                            |       |
+   *                                          __*__   __*__
+   *                                          |   |   |   |
+   *                                          a   b   d   e
+   *
+   *
+   *
+   */
+  it('two deep leafless splits ', async () => {
+    const storage = new MemoryBlockstore()
+    const cid = CID.parse(
+      'bafyreie5cvv4h45feadgeuwhbcutmh6t2ceseocckahdoe6uat64zmz454',
+    )
+
+    let mst = await MST.create(storage)
+    mst = await mst.add(k.A0, cid)
+    mst = await mst.add(k.B0, cid)
+    mst = await mst.add(k.D0, cid)
+    mst = await mst.add(k.E0, cid)
+
+    const pointerBeforeOp = await mst.getPointer()
+
+    mst = await mst.add(k.C2, cid)
+    const proof = await mst.getCoveringProof(k.C2)
+
+    const proofStorage = new MemoryBlockstore(proof)
+    let proofMst = await MST.load(proofStorage, await mst.getPointer())
+    proofMst = await proofMst.delete(k.C2)
+    const pointerAfterInvert = await proofMst.getPointer()
+    expect(pointerAfterInvert.equals(pointerBeforeOp)).toBe(true)
+  })
+})