refactor(web): make SearchResult's node-path accessible

This was formerly part of #14987 and has been extracted for ease of review.

Build-bot: skip build:web
Test-bot: skip

Author: jahorton

web/src/engine/predictive-text/worker-thread/src/main/correction/distance-modeler.ts

@@ -5,8 +5,7 @@ import { LexicalModelTypes } from '@keymanapp/common-types';
 
 import { ClassicalDistanceCalculation } from './classical-calculation.js';
 import { ExecutionTimer, STANDARD_TIME_BETWEEN_DEFERS } from './execution-timer.js';
-import { QUEUE_NODE_COMPARATOR, SearchQuotientSpur } from './search-quotient-spur.js';
-import { PathResult } from './search-quotient-node.js';
+import { PathResult, SearchQuotientNode } from './search-quotient-node.js';
 import { subsetByChar, subsetByInterval, mergeSubset, TransformSubset } from '../transform-subsets.js';
 import TransformUtils from '../transformUtils.js';
 
@@ -571,22 +570,22 @@ export class SearchNode {
 }
 
 export class SearchResult {
-  private resultNode: SearchNode;
+  readonly node: SearchNode;
 
   constructor(node: SearchNode) {
-    this.resultNode = node;
+    this.node = node;
   }
 
   get inputSequence(): ProbabilityMass<Transform>[] {
-    return this.resultNode.priorInput;
+    return this.node.priorInput;
   }
 
   get matchSequence(): TraversableToken<string>[] {
-    return this.resultNode.calculation.matchSequence.map((char, i) => ({key: char, traversal: this.resultNode.matchedTraversals[i+1]}));
+    return this.node.calculation.matchSequence.map((char, i) => ({key: char, traversal: this.node.matchedTraversals[i+1]}));
   };
 
   get matchString(): string {
-    return this.resultNode.resultKey;
+    return this.node.resultKey;
   }
 
   /**
@@ -597,15 +596,15 @@ export class SearchResult {
    * `totalCost`.)
    */
   get knownCost(): number {
-    return this.resultNode.editCount;
+    return this.node.editCount;
   }
 
   /**
    * Gets the "input sampling cost" of the edge, which should be considered as the
    * negative log-likelihood of the input path taken to reach the node.
    */
   get inputSamplingCost(): number {
-    return this.resultNode.inputSamplingCost;
+    return this.node.inputSamplingCost;
   }
 
   /**
@@ -615,41 +614,34 @@ export class SearchResult {
    * to the resulting output.
    */
   get totalCost(): number {
-    return this.resultNode.currentCost;
+    return this.node.currentCost;
   }
 
   get finalTraversal(): LexiconTraversal {
-    return this.resultNode.currentTraversal;
+    return this.node.currentTraversal;
   }
 
   get spaceId(): number {
-    return this.resultNode.spaceId;
+    return this.node.spaceId;
   }
 }
 
 // Current best guesstimate of how compositor will retrieve ideal corrections.
-export async function *getBestMatches(searchSpace: SearchQuotientSpur, timer: ExecutionTimer): AsyncGenerator<SearchResult> {
+export async function *getBestMatches(searchSpace: SearchQuotientNode, timer: ExecutionTimer): AsyncGenerator<SearchResult> {
   let currentReturns: {[resultKey: string]: SearchNode} = {};
 
   // Stage 1 - if we already have extracted results, build a queue just for them and iterate over it first.
-  const returnedValues = Object.values(searchSpace.returnedValues);
+  const returnedValues = Object.values(searchSpace.previousResults);
   if(returnedValues.length > 0) {
-    let preprocessedQueue = new PriorityQueue<SearchNode>(QUEUE_NODE_COMPARATOR, returnedValues);
+    let preprocessedQueue = new PriorityQueue<SearchResult>((a, b) => a.totalCost - b.totalCost, returnedValues);
 
     while(preprocessedQueue.count > 0) {
       const entryFromCache = timer.time(() => {
         let entry = preprocessedQueue.dequeue();
 
-        // Is the entry a reasonable result?
-        if(entry.isFullReplacement) {
-          // If the entry's 'match' fully replaces the input string, we consider it
-          // unreasonable and ignore it.
-          return null;
-        }
-
-        currentReturns[entry.resultKey] = entry;
+        currentReturns[entry.node.resultKey] = entry.node;
         // Do not track yielded time.
-        return new SearchResult(entry);
+        return entry;
       }, TimedTaskTypes.CACHED_RESULT);
 
       if(entryFromCache) {

web/src/engine/predictive-text/worker-thread/src/main/correction/search-quotient-spur.ts

@@ -33,22 +33,11 @@ export class SearchQuotientSpur implements SearchQuotientNode {
   private parentPath: SearchQuotientSpur;
   readonly spaceId: number;
 
-  // We use an array and not a PriorityQueue b/c batch-heapifying at a single point in time
-  // is cheaper than iteratively building a priority queue.
-  /**
-   * This tracks all paths that have reached the end of a viable input-matching path - even
-   * those of lower cost that produce the same correction as other paths.
-   *
-   * When new input is received, its entries are then used to append edges to the path in order
-   * to find potential paths to reach a new viable end.
-   */
-  private completedPaths?: SearchNode[] = [];
-
   /**
    * Marks all results that have already been returned since the last input was received.
    * Is cleared after .addInput() calls.
    */
-  public returnedValues?: {[resultKey: string]: SearchNode} = {}; // TODO:  make it private again!
+  private returnedValues?: {[resultKey: string]: SearchNode} = {};
 
   /**
    * Provides a heuristic for the base cost at each depth if the best
@@ -75,15 +64,14 @@ export class SearchQuotientSpur implements SearchQuotientNode {
       this.lowestCostAtDepth = parentNode.lowestCostAtDepth.concat(logTierCost);
       this.parentPath = parentNode;
 
-      this.addEdgesForNodes(parentNode.completedPaths);
+      this.addEdgesForNodes(parentNode.previousResults.map(v => v.node));
 
       return;
     }
 
     const model = arg1 as LexicalModel;
     this.selectionQueue.enqueue(new SearchNode(model.traverseFromRoot(), this.spaceId, t => model.toKey(t)));
     this.lowestCostAtDepth = [];
-    this.completedPaths = [];
   }
 
   /**
@@ -236,9 +224,6 @@ export class SearchQuotientSpur implements SearchQuotientNode {
       this.selectionQueue.enqueueAll(insertionEdges);
     }
 
-    // It was the final tier - store the node for future reference.
-    this.completedPaths?.push(currentNode);
-
     if((this.returnedValues[currentNode.resultKey]?.currentCost ?? Number.POSITIVE_INFINITY) > currentNode.currentCost) {
       this.returnedValues[currentNode.resultKey] = currentNode;
     } else {
@@ -255,6 +240,6 @@ export class SearchQuotientSpur implements SearchQuotientNode {
   }
 
   public get previousResults(): SearchResult[] {
-    return Object.values(this.returnedValues).map(v => new SearchResult(v));
+    return Object.values(this.returnedValues ?? {}).map(v => new SearchResult(v));
   }
 }