cache enabled status per-logger (#799)

Co-authored-by: Qix <[email protected]>

src/common.js

@@ -60,6 +60,8 @@ function setup(env) {
  function createDebug(namespace) {
  let prevTime;
  let enableOverride = null;
+ let namespacesCache;
+ let enabledCache;
 
  function debug(...args) {
  // Disabled?
@@ -120,7 +122,17 @@ function setup(env) {
  Object.defineProperty(debug, 'enabled', {
  enumerable: true,
  configurable: false,
- get: () => enableOverride === null ? createDebug.enabled(namespace) : enableOverride,
+ get: () => {
+ if (enableOverride !== null) {
+ return enableOverride;
+ }
+ if (namespacesCache !== createDebug.namespaces) {
+ namespacesCache = createDebug.namespaces;
+ enabledCache = createDebug.enabled(namespace);
+ }
+
+ return enabledCache;
+ },
  set: v => {
  enableOverride = v;
  }
@@ -149,6 +161,7 @@ function setup(env) {
  */
  function enable(namespaces) {
  createDebug.save(namespaces);
+ createDebug.namespaces = namespaces;
 
  createDebug.names = [];
  createDebug.skips = [];