refactor: replace ignored numeric literals with constants

src/modules/investments/instruments/application/catalog-discovery.service.ts

@@ -26,6 +26,10 @@ import {
   selectCatalogInstruments,
 } from './catalog-selection';
 
+const UNAMBIGUOUS_MATCH_COUNT = 1;
+const NO_MATCHES = 0;
+const FIRST_RESULT_OFFSET = 0;
+
 const tickerAmbiguityLimit = 2;
 
 type Producer = {
@@ -160,7 +164,7 @@ export class CatalogDiscoveryService {
         { instrumentType, query: instrument.ticker, exactTicker: true },
         observe,
       );
-      if (alias.data?.length === 1 && alias.data[0].uid === uid) {
+      if (alias.data?.length === UNAMBIGUOUS_MATCH_COUNT && alias.data[0].uid === uid) {
         slug = instrument.ticker.toUpperCase();
       }
       dependencies.push(alias.meta);
@@ -200,8 +204,8 @@ export class CatalogDiscoveryService {
       { instrumentType, query: ticker, exactTicker: true },
       observe,
     );
-    if (lookup.data?.length === 0) throw new NotFoundException();
-    if (lookup.data && lookup.data.length > 1) {
+    if (lookup.data?.length === NO_MATCHES) throw new NotFoundException();
+    if (lookup.data && lookup.data.length > UNAMBIGUOUS_MATCH_COUNT) {
       throw new ConflictException({
         code:
           instrumentType === 'share' ?
@@ -346,7 +350,7 @@ export class CatalogDiscoveryService {
                 input.query,
                 input.instrumentType,
               ).slice(
-                0,
+                FIRST_RESULT_OFFSET,
                 input.exactTicker ? tickerAmbiguityLimit : catalogSearchLimit,
               ),
               new Date(),
@@ -364,7 +368,7 @@ export class CatalogDiscoveryService {
         if (success) {
           const saved = await this.repository.read(input);
           for (const observer of [attempt, ...producer.observers]) {
-            if (!input.exactTicker || saved.data?.length === 1) {
+            if (!input.exactTicker || saved.data?.length === UNAMBIGUOUS_MATCH_COUNT) {
               await this.enrichment.requestMany(
                 observer.userId,
                 observer.revision,