Remove Score as we no longer need that abstraction. (#8289)

Author: isoos

app/lib/search/mem_index.dart

@@ -479,7 +479,7 @@ class PackageNameIndex {
 
   /// Search [text] and return the matching packages with scores.
   @visibleForTesting
-  Score search(String text) {
+  Map<String, double> search(String text) {
     IndexedScore<String>? score;
     for (final w in splitForQuery(text)) {
       final s = searchWord(w, filterOnNonZeros: score);
@@ -489,7 +489,7 @@ class PackageNameIndex {
         score.multiplyAllFrom(s);
       }
     }
-    return score?.toScore() ?? Score.empty;
+    return score?.toMap() ?? {};
   }
 
   /// Search using the parsed [word] and return the matching packages with scores

app/lib/search/sdk_mem_index.dart

@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'dart:math';
+
 import 'package:_pub_shared/utils/http.dart';
 // ignore: implementation_imports
 import 'package:pana/src/dartdoc/dartdoc_index.dart';
@@ -135,18 +137,17 @@ class SdkMemIndex {
       final isQualifiedQuery = query.contains(library.split(':').last);
 
       final tokens = _tokensPerLibrary[library]!;
-      final plainResults =
-          Score(tokens.searchWords(words).top(3, minValue: 0.05));
+      final plainResults = tokens.searchWords(words).top(3, minValue: 0.05);
       if (plainResults.isEmpty) continue;
 
       final libraryWeight = _libraryWeights[library] ?? 1.0;
       final weightedResults = isQualifiedQuery
           ? plainResults
-          : plainResults.mapValues(
+          : plainResults.map(
               (key, value) {
                 final dir = p.dirname(key);
                 final w = (_apiPageDirWeights[dir] ?? 1.0) * libraryWeight;
-                return w * value;
+                return MapEntry(key, w * value);
               },
             );
 
@@ -185,9 +186,9 @@ class SdkMemIndex {
 
 class _Hit {
   final String library;
-  final Score top;
+  final Map<String, double> top;
 
   _Hit(this.library, this.top);
 
-  late final score = top.maxValue;
+  late final score = top.values.fold(0.0, (a, b) => max(a, b));
 }

app/lib/search/token_index.dart

@@ -8,24 +8,6 @@ import 'package:meta/meta.dart';
 
 import 'text_utils.dart';
 
-/// Represents an evaluated score as an {id: score} map.
-extension type const Score._(Map<String, double> _values)
-    implements Map<String, double> {
-  static const Score empty = Score._({});
-
-  Score(this._values);
-
-  factory Score.fromEntries(Iterable<MapEntry<String, double>> entries) =>
-      Score(Map.fromEntries(entries));
-
-  double get maxValue => _values.values.fold(0.0, math.max);
-
-  /// Transfer the score values with [f].
-  Score mapValues(double Function(String key, double value) f) =>
-      Score.fromEntries(
-          _values.entries.map((e) => MapEntry(e.key, f(e.key, e.value))));
-}
-
 /// The weighted tokens used for the final search.
 class TokenMatch {
   final Map<String, double> _tokenWeights = <String, double>{};
@@ -151,7 +133,7 @@ extension StringTokenIndexExt on TokenIndex<String> {
   /// scoring.
   @visibleForTesting
   Map<String, double> search(String text) {
-    return searchWords(splitForQuery(text)).toScore();
+    return searchWords(splitForQuery(text)).toMap();
   }
 }
 
@@ -250,17 +232,15 @@ class IndexedScore<K> {
     }
     return Map.fromEntries(list.map((i) => MapEntry(_keys[i], _values[i])));
   }
-}
 
-extension StringIndexedScoreExt on IndexedScore<String> {
-  Score toScore() {
-    final map = <String, double>{};
+  Map<K, double> toMap() {
+    final map = <K, double>{};
     for (var i = 0; i < _values.length; i++) {
       final v = _values[i];
       if (v > 0.0) {
         map[_keys[i]] = v;
       }
     }
-    return Score._(map);
+    return map;
   }
 }