Cache segment (#72)

* Cache pseq segment

* Bump version

* Fix caching

common/config/rush/version-policies.json

@@ -2,7 +2,7 @@
   {
     "policyName": "public",
     "definitionName": "lockStepVersion",
-    "version": "0.0.0-alpha.3",
+    "version": "0.0.0-alpha.4",
     "nextBump": "prerelease"
   }
 ]

packages/common/tool-config/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@tiny-calc/tool-config",
-  "version": "0.0.0-alpha.3",
+  "version": "0.0.0-alpha.4",
   "description": "Common config for build tools",
   "sideEffects": "false",
   "repository": {

packages/core/micro/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@tiny-calc/micro",
-  "version": "0.0.0-alpha.3",
+  "version": "0.0.0-alpha.4",
   "main": "dist/index.js",
   "sideEffects": "false",
   "repository": {
@@ -19,10 +19,10 @@
     "adjust-random": "ts-node test/random-adjust-tree.ts"
   },
   "dependencies": {
-    "@tiny-calc/nano": "0.0.0-alpha.3"
+    "@tiny-calc/nano": "0.0.0-alpha.4"
   },
   "devDependencies": {
-    "@tiny-calc/tool-config": "0.0.0-alpha.3",
+    "@tiny-calc/tool-config": "0.0.0-alpha.4",
     "@types/mocha": "^5.2.6",
     "@types/node": "^10.0.0",
     "best-random": "^1.0.3",

packages/core/micro/src/adjust-tree/tree.ts

@@ -75,9 +75,8 @@ export class AdjustTreeBase<T> {
             ({ index, offset } = find(node, offset));
             node = node.segments[index];
         }
-        const segmentStart = position - offset;
         ({ index, offset } = find(node, offset));
-        return { segmentStart, index, offset, leaf: node }
+        return { offset, index, leaf: node }
     }
 
     getItem(position: number): { offset: number, segment: T } {

packages/core/micro/src/adjust-tree/types.ts

@@ -14,9 +14,8 @@ export interface InteriorNode<T> extends RopeBase<AdjustNode<T>> {
 }
 
 export interface LeafFocus<T> {
-    segmentStart: number;
-    index: number;
     offset: number;
+    index: number;
     leaf: LeafNode<T>;
 }
 

packages/core/micro/src/permutation/index.ts

@@ -1,5 +1,5 @@
 import { AdjustTree, createTree, SegmentRange, TreeConfiguration, loadTree, forEachInSegmentRange } from "../adjust-tree/index";
-import { LeafFocus } from "../adjust-tree/types";
+import { LeafNode, LeafFocus } from "../adjust-tree/types";
 
 const enum PermutationKind {
     Empty,
@@ -306,6 +306,9 @@ export class PermutationSequence {
     next: number;
     recycler: Recycler;
     focus: LeafFocus<PermutationSegment> | undefined;
+    cachedSegment: PermutationSegment | undefined;
+    segmentStart: number | undefined;
+    segmentEnd: number | undefined;
 
     constructor(snapshot?: PermutationSequenceSnapshot) {
         if (snapshot) {
@@ -336,14 +339,29 @@ export class PermutationSequence {
         if (position < 0 || position >= this.permutationTree.getLength()) {
             return undefined;
         }
-        const focus = this.permutationTree.zoom(position);
-        const { offset, index, leaf } = focus
-        const segment = leaf.segments[index];
+        
+        let segment: PermutationSegment | undefined;
+        let offset: number;
+        let leaf: LeafNode<PermutationSegment>;
+        let index: number;
+        
+        if (this.cachedSegment && position >= this.segmentStart! && position < this.segmentEnd!) {
+            segment = this.cachedSegment;
+            offset = position - this.segmentStart!;
+            ({ index, leaf } = this.focus!);
+        }
+        else {
+            ({ index, offset, leaf } = this.focus = this.permutationTree.zoom(position));
+            this.cachedSegment = segment = leaf.segments[index];
+            this.segmentStart = position - offset;
+            this.segmentEnd = this.segmentStart + leaf.lengths[index];
+        }
+        
         switch (segment.kind) {
             case PermutationKind.Empty:
                 const fresh = this.freshPermutation();
                 const len = leaf.lengths[index];
-                leaf.segments[index] = singleton(offset, len, fresh);
+                leaf.segments[index] = this.cachedSegment = singleton(offset, len, fresh);
                 return fresh;
 
             case PermutationKind.Direct:
@@ -362,7 +380,22 @@ export class PermutationSequence {
         if (position < 0 || position >= this.permutationTree.getLength()) {
             return undefined;
         }
-        const { offset, segment } = this.permutationTree.getItem(position);
+        
+        let segment: PermutationSegment | undefined;
+        let offset: number;
+        if (this.cachedSegment && position >= this.segmentStart! && position < this.segmentEnd!) {
+            segment = this.cachedSegment;
+            offset = position - this.segmentStart!;
+        }
+        else {
+            let index: number;
+            let leaf: LeafNode<PermutationSegment>;
+            ({ index, offset, leaf } = this.focus = this.permutationTree.zoom(position));
+            this.cachedSegment = segment = leaf.segments[index];
+            this.segmentStart = position - offset;
+            this.segmentEnd = this.segmentStart + leaf.lengths[index];
+        }
+        
         switch (segment.kind) {
             case PermutationKind.Empty:
                 return UNALLOCATED;
@@ -377,6 +410,7 @@ export class PermutationSequence {
 
     insertRange(position: number, length: number) {
         this.permutationTree.insertRange(position, length, empty);
+        this.cachedSegment = undefined;
     }
 
     insertFilledRange(position: number, length: number) {
@@ -394,6 +428,7 @@ export class PermutationSequence {
             this.permutationTree.insertRange(pos, remaining, { kind: PermutationKind.RunLength, content: [remaining, this.next] });
             this.next += remaining;
         }
+        this.cachedSegment = undefined;
     }
 
     map<T>(cb: (pos: number, perm: number) => T): T[] {
@@ -484,6 +519,7 @@ export class PermutationSequence {
     }
 
     deleteRange(position: number, length: number) {
+        this.cachedSegment = undefined;
         return this.permutationTree.deleteRange(position, length);
     }
 

packages/core/nano/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@tiny-calc/nano",
-  "version": "0.0.0-alpha.3",
+  "version": "0.0.0-alpha.4",
   "main": "dist/index.js",
   "sideEffects": "false",
   "repository": {
@@ -17,7 +17,7 @@
     "test": "mocha -r ts-node/register test/**/*.spec.ts"
   },
   "devDependencies": {
-    "@tiny-calc/tool-config": "0.0.0-alpha.3",
+    "@tiny-calc/tool-config": "0.0.0-alpha.4",
     "@types/benchmark": "^1.0.31",
     "@types/mocha": "^5.2.6",
     "@types/node": "^10.0.0",

packages/test/example/package.json

@@ -15,11 +15,11 @@
     "test": "ts-node src/index.ts"
   },
   "dependencies": {
-    "@tiny-calc/nano": "0.0.0-alpha.3",
+    "@tiny-calc/nano": "0.0.0-alpha.4",
     "node-fetch": "^2.6.0"
   },
   "devDependencies": {
-    "@tiny-calc/tool-config": "0.0.0-alpha.3",
+    "@tiny-calc/tool-config": "0.0.0-alpha.4",
     "@types/node": "^10.0.0",
     "rimraf": "^2.6.3",
     "ts-node": "^8.1.0",