Move rationale to code and implement invalidate cache

README.md

@@ -693,15 +693,6 @@ With this option enabled only environment variables starting with
 i.e. The environment variable `CONFIG_FORCE_a_b__c___d` set the
 configuration key `a.b-c_d`
 
-Rationale the name mangling:
-
-Most shells (e.g. bash, sh, etc.) doesn't support any character other
-than alphanumeric and `_` in environment variables names.
-In HOCON the default separator is `.` so it is directly translated to a
-single `_` for convenience; `-` and `_` are less often present in config
-keys but they have to be representable and the only possible mapping is
-`_` repeated.
-
 ### Concatenation
 
 Values _on the same line_ are concatenated (for strings and

config/src/main/java/com/typesafe/config/ConfigFactory.java

@@ -502,6 +502,7 @@ public static void invalidateCaches() {
  // all caches
  ConfigImpl.reloadSystemPropertiesConfig();
  ConfigImpl.reloadEnvVariablesConfig();
+ ConfigImpl.reloadEnvVariablesOverridesConfig();
  }
 
  /**

config/src/main/java/com/typesafe/config/impl/ConfigImpl.java

@@ -364,6 +364,14 @@ public static void reloadEnvVariablesConfig() {
  private static AbstractConfigObject loadEnvVariablesOverrides() {
  Map<String, String> env = new HashMap(System.getenv());
  Map<String, String> result = new HashMap(System.getenv());
+ // Rationale on name mangling:
+ //
+ // Most shells (e.g. bash, sh, etc.) doesn't support any character other
+ // than alphanumeric and `_` in environment variables names.
+ // In HOCON the default separator is `.` so it is directly translated to a
+ // single `_` for convenience; `-` and `_` are less often present in config
+ // keys but they have to be representable and the only possible mapping is
+ // `_` repeated.
  for (String key : env.keySet()) {
  if (key.startsWith(ENV_VAR_OVERRIDE_PREFIX)) {
  StringBuilder builder = new StringBuilder();
@@ -412,6 +420,12 @@ public static Config envVariablesOverridesAsConfig() {
  return envVariablesOverridesAsConfigObject().toConfig();
  }
 
+ public static void reloadEnvVariablesOverridesConfig() {
+ // ConfigFactory.invalidateCaches() relies on this having the side
+ // effect that it drops all caches
+ EnvVariablesOverridesHolder.envVariables = loadEnvVariablesOverrides();
+ }
+
  public static Config defaultReference(final ClassLoader loader) {
  return computeCachedConfig(loader, "defaultReference", new Callable<Config>() {
  @Override