From 6a19cd91a8f24b01d848e8455260ff2419b96b97 Mon Sep 17 00:00:00 2001
From: Andre Staltz <andre@staltz.com>
Date: Fri, 14 Apr 2023 16:41:25 +0300
Subject: [PATCH] return Sets from some Tangle APIs

---
 lib/tangle.js       | 32 ++++++++++++++++++++++++------
 test/tangle.test.js | 48 +++++++++++++++++++++++++++++++++++----------
 2 files changed, 64 insertions(+), 16 deletions(-)

diff --git a/lib/tangle.js b/lib/tangle.js
index 8db8ffb..88b299d 100644
--- a/lib/tangle.js
+++ b/lib/tangle.js
@@ -60,12 +60,18 @@ class Tangle {
    */
   #perDepth = new Map()
 
+  /**
+   * @type {number}
+   */
+  #maxDepth
+
   /**
    *
    * @param {string} rootHash
    * @param {Iterable<Rec>} recordsIter
    */
   constructor(rootHash, recordsIter) {
+    this.#maxDepth = 0
     for (const rec of recordsIter) {
       const msgHash = rec.hash
       const tangles = rec.msg.metadata.tangles
@@ -81,6 +87,7 @@ class Tangle {
         }
         this.#prev.set(msgHash, prev)
         const depth = tangles[rootHash].depth
+        if (depth > this.#maxDepth) this.#maxDepth = depth
         this.#depth.set(msgHash, depth)
         const atDepth = this.#perDepth.get(depth) ?? []
         atDepth.push(msgHash)
@@ -103,7 +110,8 @@ class Tangle {
    */
   topoSort() {
     const sorted = []
-    for (let i = 0; i < 1e9; i++) {
+    const max = this.#maxDepth
+    for (let i = 0; i <= max; i++) {
       const atDepth = this.#getAllAtDepth(i)
       if (atDepth.length === 0) break
       for (const msgHash of atDepth) {
@@ -114,19 +122,19 @@ class Tangle {
   }
 
   /**
-   * @returns {Array<string>}
+   * @returns {Set<string>}
    */
   getTips() {
-    return [...this.#tips]
+    return this.#tips
   }
 
   /**
    * @param {number} depth
-   * @returns {Array<string>}
+   * @returns {Set<string>}
    */
-  getLipmaa(depth) {
+  getLipmaaSet(depth) {
     const lipmaaDepth = lipmaa(depth + 1) - 1
-    return this.#getAllAtDepth(lipmaaDepth)
+    return new Set(this.#getAllAtDepth(lipmaaDepth))
   }
 
   /**
@@ -137,6 +145,14 @@ class Tangle {
     return this.#depth.has(msgHash)
   }
 
+  /**
+   * @param {string} msgHash
+   * @returns {number}
+   */
+  getDepth(msgHash) {
+    return this.#depth.get(msgHash) ?? -1
+  }
+
   #shortestPathToRoot(msgHash) {
     const path = []
     let current = msgHash
@@ -169,6 +185,10 @@ class Tangle {
     )
     return { deletables, emptyables }
   }
+
+  getMaxDepth() {
+    return this.#maxDepth
+  }
 }
 
 module.exports = Tangle
diff --git a/test/tangle.test.js b/test/tangle.test.js
index 5892221..fa90ae9 100644
--- a/test/tangle.test.js
+++ b/test/tangle.test.js
@@ -96,6 +96,23 @@ test('Tangle.has', (t) => {
   t.end()
 })
 
+test('Tangle.getDepth', t=> {
+  const tangle = new Tangle(rootPost, peer.db.records())
+  t.equals(tangle.getDepth(rootPost), 0, 'depth of rootPost is 0')
+  t.equals(tangle.getDepth(reply1Lo), 1, 'depth of reply1Lo is 1')
+  t.equals(tangle.getDepth(reply1Hi), 1, 'depth of reply1Hi is 1')
+  t.equals(tangle.getDepth(reply2A), 2, 'depth of reply2A is 2')
+  t.equals(tangle.getDepth(reply3Lo), 3, 'depth of reply3Lo is 3')
+  t.equals(tangle.getDepth(reply3Hi), 3, 'depth of reply3Hi is 3')
+  t.end()
+})
+
+test('Tangle.getMaxDepth', t => {
+  const tangle = new Tangle(rootPost, peer.db.records())
+  t.equals(tangle.getMaxDepth(), 3, 'max depth is 3')
+  t.end()
+})
+
 test('Tangle.topoSort', (t) => {
   const tangle = new Tangle(rootPost, peer.db.records())
   const sorted = tangle.topoSort()
@@ -115,20 +132,31 @@ test('Tangle.getTips', (t) => {
   const tangle = new Tangle(rootPost, peer.db.records())
   const tips = tangle.getTips()
 
-  t.equals(tips.length, 2, 'there are 2 tips')
-  t.true(tips.includes(reply3Lo), 'tips contains reply3Lo')
-  t.true(tips.includes(reply3Hi), 'tips contains reply3Hi')
+  t.equals(tips.size, 2, 'there are 2 tips')
+  t.true(tips.has(reply3Lo), 'tips contains reply3Lo')
+  t.true(tips.has(reply3Hi), 'tips contains reply3Hi')
   t.end()
 })
 
-test('Tangle.getLipmaa', (t) => {
+test('Tangle.getLipmaaSet', (t) => {
   const tangle = new Tangle(rootPost, peer.db.records())
-  t.deepEquals(tangle.getLipmaa(0), [], 'lipmaa 0 (empty)')
-  t.deepEquals(tangle.getLipmaa(1), [rootPost], 'lipmaa 1 (-1)')
-  t.deepEquals(tangle.getLipmaa(2), [reply1Lo, reply1Hi], 'lipmaa 2 (-1)')
-  t.deepEquals(tangle.getLipmaa(3), [rootPost], 'lipmaa 3 (leap!)')
-  t.deepEquals(tangle.getLipmaa(4), [reply3Lo, reply3Hi], 'lipmaa 4 (-1)')
-  t.deepEquals(tangle.getLipmaa(5), [], 'lipmaa 5 (empty)')
+  t.equals(tangle.getLipmaaSet(0).size, 0, 'lipmaa 0 (empty)')
+
+  t.equals(tangle.getLipmaaSet(1).size, 1, 'lipmaa 1 (-1)')
+  t.true(tangle.getLipmaaSet(1).has(rootPost), 'lipmaa 1 (-1)')
+
+  t.equals(tangle.getLipmaaSet(2).size, 2, 'lipmaa 2 (-1)')
+  t.true(tangle.getLipmaaSet(2).has(reply1Lo), 'lipmaa 2 (-1)')
+  t.true(tangle.getLipmaaSet(2).has(reply1Hi), 'lipmaa 2 (-1)')
+
+  t.equals(tangle.getLipmaaSet(3).size, 1, 'lipmaa 3 (leap!)')
+  t.true(tangle.getLipmaaSet(3).has(rootPost), 'lipmaa 3 (leap!)')
+
+  t.equals(tangle.getLipmaaSet(4).size, 2, 'lipmaa 4 (-1)')
+  t.true(tangle.getLipmaaSet(4).has(reply3Lo), 'lipmaa 4 (-1)')
+  t.true(tangle.getLipmaaSet(4).has(reply3Hi), 'lipmaa 4 (-1)')
+
+  t.equals(tangle.getLipmaaSet(5).size, 0, 'lipmaa 5 (empty)')
 
   t.end()
 })