Update file-search to prioritize exact matches

Fixes #5636

Fixes an issue where `exact` file results were not being
displayed since `fuzzy` matches were added instead. Due
to the limit present when searching for files, `exact` matches
should be prioritized more while `fuzzy` matches should be
used to fill up the result list if necessary. Adjusting the
code means that better results are returned, and for an
end-user, they get more consistent results in respect to their
workspace.

Signed-off-by: Vincent Fugnitto <vincent.fugnitto@ericsson.com>

packages/file-search/src/node/file-search-service-impl.ts

@@ -68,35 +68,45 @@ export class FileSearchServiceImpl implements FileSearchService {
             }
         }
 
-        const exactMatches = new Set<string>();
-        const fuzzyMatches = new Set<string>();
+        const matches = new Set<string>();
+
         const stringPattern = searchPattern.toLocaleLowerCase();
         await Promise.all(Object.keys(roots).map(async root => {
             try {
                 const rootUri = new URI(root);
                 const rootOptions = roots[root];
-                await this.doFind(rootUri, rootOptions, candidate => {
-                    const fileUri = rootUri.resolve(candidate).toString();
-                    if (exactMatches.has(fileUri) || fuzzyMatches.has(fileUri)) {
-                        return;
-                    }
-                    if (!searchPattern || searchPattern === '*' || candidate.toLocaleLowerCase().indexOf(stringPattern) !== -1) {
-                        exactMatches.add(fileUri);
-                    } else if (opts.fuzzyMatch && fuzzy.test(searchPattern, candidate)) {
-                        fuzzyMatches.add(fileUri);
-                    }
-                    if (exactMatches.size + fuzzyMatches.size === opts.limit) {
-                        cancellationSource.cancel();
-                    }
-                }, token);
+                // Perform searches for `exact` and `fuzzy` matches in parallel.
+                await Promise.all([
+                    // Get 'exact' match results.
+                    this.doFind(rootUri, rootOptions, candidate => {
+                        const fileUri = rootUri.resolve(candidate).toString();
+                        if (!searchPattern || searchPattern === '*' || candidate.toLocaleLowerCase().indexOf(stringPattern) !== -1) {
+                            if (matches.size === opts.limit) {
+                                cancellationSource.cancel();
+                            }
+                            matches.add(fileUri);
+                        }
+                    }, token),
+                    // Get the 'fuzzy' match results.
+                    this.doFind(rootUri, rootOptions, candidate => {
+                        const fileUri = rootUri.resolve(candidate).toString();
+                        if (opts.fuzzyMatch && fuzzy.test(searchPattern, candidate)) {
+                            if (matches.size === opts.limit) {
+                                cancellationSource.cancel();
+                            }
+                            matches.add(fileUri);
+                        }
+                    }, token)
+                ]);
             } catch (e) {
                 console.error('Failed to search:', root, e);
             }
         }));
         if (clientToken && clientToken.isCancellationRequested) {
             return [];
         }
-        return [...exactMatches, ...fuzzyMatches];
+
+        return [...matches];
     }
 
     private doFind(rootUri: URI, options: FileSearchService.BaseOptions,