angular-docs-cn/aio/tools/transforms/target-package/services/targetEnvironments.js

52 lines
1.3 KiB
JavaScript

module.exports = function targetEnvironments() {
var _targets = Object.create(null);
var _activeCount = 0;
var checkAllowed = function(target) {
if (!(target in _targets)) {
throw new Error(
'Error accessing target "' + target + '". It is not in the list of allowed targets: ' +
Object.keys(_targets));
}
};
var updateActiveCount = function() {
_activeCount = 0;
for (let target in _targets) {
if (_targets[target]) _activeCount++;
}
};
return {
addAllowed: function(target, isActive) {
_targets[target] = !!isActive;
updateActiveCount();
},
removeAllowed: function(target) {
delete _targets[target];
updateActiveCount();
},
activate: function(target) {
checkAllowed(target);
_targets[target] = true;
updateActiveCount();
},
deactivate: function(target) {
checkAllowed(target);
_targets[target] = false;
updateActiveCount();
},
isActive: function(target) {
checkAllowed(target);
return _targets[target];
},
hasActive: function() { return _activeCount > 0; },
someActive: function(targets) {
for (var i = 0, ii = targets.length; i < ii; i++) {
if (this.isActive(targets[i])) return true;
}
return false;
}
};
};