memoize option for fallback

CHANGELOG.md

@@ -1,3 +1,6 @@
+### 0.4.0
+- with i18next >=v11.3.3 only memoize if successful lookup
+
 ### 0.3.0
 - allow to pass in localeData in init options
 

README.md

@@ -70,6 +70,9 @@ i18next
   // per default icu functions are parsed once and cached for subsequent calls
   memoize: true,
 
+  // memoize if not having a lookup and just using the key fallback as value
+  memoizeFallback: false,
+
   // array or single object of loaded 'i18next-icu/locale-data
   localeData: null
 }

i18nextICU.js

@@ -2000,7 +2000,8 @@ function _classCallCheck(instance, Constructor) { if (!(instance instanceof Cons
 
 function getDefaults() {
   return {
-    memoize: true
+    memoize: true,
+    memoizeFallback: false
   };
 }
 
@@ -2041,14 +2042,16 @@ var ICU = function () {
     }
   }, {
     key: 'parse',
-    value: function parse(res, options, lng, ns, key) {
+    value: function parse(res, options, lng, ns, key, info) {
+      var hadSuccessfulLookup = info && info.resolved && info.resolved.res;
+
       var fc = void 0;
       if (this.options.memoize) {
         fc = getPath(this.mem, lng + '.' + ns + '.' + key);
       }
       if (!fc) {
         fc = new MessageFormat(res, lng);
-        if (this.options.memoize) setPath(this.mem, lng + '.' + ns + '.' + key, fc);
+        if (this.options.memoize && (this.options.memoizeFallback || !info || hadSuccessfulLookup)) setPath(this.mem, lng + '.' + ns + '.' + key, fc);
       }
       return fc.format(options);
     }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "i18next-icu",
-  "version": "0.3.0",
+  "version": "0.4.0",
   "description": "i18nFormat plugin to use ICU format with i18next",
   "main": "./index.js",
   "jsnext:main": "dist/es/index.js",

src/index.js

@@ -3,7 +3,8 @@ import IntlMessageFormat from 'intl-messageformat';
 
 function getDefaults() {
   return {
-    memoize: true
+    memoize: true,
+    memoizeFallback: false
   };
 }
 
@@ -38,14 +39,16 @@ class ICU {
     });
   }
 
-  parse(res, options, lng, ns, key) {
+  parse(res, options, lng, ns, key, info) {
+    const hadSuccessfulLookup = info && info.resolved && info.resolved.res;
+
     let fc;
     if (this.options.memoize) {
       fc = utils.getPath(this.mem, `${lng}.${ns}.${key}`);
     }
     if (!fc) {
       fc = new IntlMessageFormat(res, lng);
-      if (this.options.memoize) utils.setPath(this.mem, `${lng}.${ns}.${key}`, fc);
+      if (this.options.memoize && (this.options.memoizeFallback || !info || hadSuccessfulLookup)) utils.setPath(this.mem, `${lng}.${ns}.${key}`, fc);
     }
     return fc.format(options);
   }