Added comment explaining use of JSON.stringify() to generate cache keys.

kulshekhar · Aug 3, 2017 · 7d9aea9 · 7d9aea9
1 parent a7fc1ae
commit 7d9aea9
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/src/utils.ts b/src/utils.ts
@@ -138,6 +138,8 @@ export function getTSConfig(globals, collectCoverage: boolean = false) {
 
   // check cache before resolving configuration
   // NB: config is a string unless taken from __TS_CONFIG__, which should be immutable (and is deprecated anyways)
+  // NB: We use JSON.stringify() to create a consistent, unique signature. Although it lacks a uniform
+  //     shape, this is simpler and faster than using the crypto package to generate a hash signature.
   const tsConfigCacheKey = JSON.stringify([skipBabel, collectCoverage, isReferencedExternalFile ? config : undefined]);
   if (tsConfigCacheKey in tsConfigCache) {
     return tsConfigCache[tsConfigCacheKey];