Copy not paying attention to upToDateWhen

I am copying some files and applying a filter to them. I want the task to depend on the file that contains the ReplaceTokens so I added an upToDateWhen closure. But it is ignored. Here is my tasks in my build.gradle file:

task filtering(type:Copy) {
from file('src/main/filtered-webapp')
into "$buildDir/webapp"

inputs.dir('filters')

def properties = new Properties()
file('filters/global-resource.filter').withReader { properties.load(it) }

filter(org.apache.tools.ant.filters.ReplaceTokens, tokens: properties)

outputs.upToDateWhen { task -> false }
}

Note:

inputs.properties properties

will not fix the problem as it is affected by the same bug