Document consensus rules from Zcash spec: Section 3.8 Note Commitment Trees

[mpguerra]

For each consensus rule:

• check that the rule is implemented in Zebra
• make sure the latest version of the rule is quoted in the docs for the code that implements it
• make sure the code implements the latest version of the rule

Implementation

Sprout

• zebra/zebra-chain/src/sprout/tree.rs

  Line 31 in 8963007

  pub(super) const MERKLE_DEPTH: usize = 29;

• zebra/zebra-chain/src/sprout/tree.rs

  Line 212 in 8963007

  inner: bridgetree::Frontier<Node, { MERKLE_DEPTH as u8 }>,

• zebra/zebra-chain/src/sprout/tree.rs

  Line 239 in 6ec42c6

  pub fn append(&mut self, cm: NoteCommitment) -> Result<(), NoteCommitmentTreeError> {

Sapling

• zebra/zebra-chain/src/sapling/tree.rs

  Line 25 in e6ffe37

  pub(super) const MERKLE_DEPTH: usize = 32;

• zebra/zebra-chain/src/sapling/tree.rs

  Line 187 in e6ffe37

  inner: bridgetree::Frontier<Node, { MERKLE_DEPTH as u8 }>,

• zebra/zebra-chain/src/sapling/tree.rs

  Line 216 in 6ec42c6

  pub fn append(&mut self, cm_u: jubjub::Fq) -> Result<(), NoteCommitmentTreeError> {

Orchard

• zebra/zebra-chain/src/orchard/tree.rs

  Line 37 in 339fefb

  pub(super) const MERKLE_DEPTH: usize = 32;

• zebra/zebra-chain/src/orchard/tree.rs

  Line 224 in 339fefb

  inner: bridgetree::Frontier<Node, { MERKLE_DEPTH as u8 }>,

• zebra/zebra-chain/src/orchard/tree.rs

  Line 253 in 6ec42c6

  pub fn append(&mut self, cm_x: pallas::Base) -> Result<(), NoteCommitmentTreeError> {

[mpguerra]

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