maven.build.cache.enable=false breaks build when maven property maven.build.cache.skipCache is set to true

[pmayweg]

Affected version

1.2.0

Bug description

When I have a project with a module with the maven property maven.build.cache.skipCache set to true and I run maven with the build cache disabled, the build fails with the stack trace:
[ERROR] Failed to calculate checksums for untitled: Cache is not initialized. Actual state: DISABLED
java.lang.RuntimeException: Failed to calculate checksums for untitled
at org.apache.maven.buildcache.DefaultProjectInputCalculator.calculateInputInternal (DefaultProjectInputCalculator.java:114)
at org.apache.maven.buildcache.DefaultProjectInputCalculator.calculateInput (DefaultProjectInputCalculator.java:89)
at org.apache.maven.buildcache.CacheControllerImpl.findCachedBuild (CacheControllerImpl.java:180)
at org.apache.maven.buildcache.BuildCacheMojosExecutionStrategy.execute (BuildCacheMojosExecutionStrategy.java:128)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:159)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:105)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:73)
at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build (SingleThreadedBuilder.java:53)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:118)
at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:261)
at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:173)
at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:101)
at org.apache.maven.cli.MavenCli.execute (MavenCli.java:906)
at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:283)
at org.apache.maven.cli.MavenCli.main (MavenCli.java:206)
at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)
at jdk.internal.reflect.NativeMethodAccessorImpl.invoke (NativeMethodAccessorImpl.java:77)
at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke (DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke (Method.java:568)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:255)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:201)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:361)
at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:314)
at org.codehaus.classworlds.Launcher.main (Launcher.java:41)
Caused by: java.lang.IllegalStateException: Cache is not initialized. Actual state: DISABLED
at org.apache.maven.buildcache.xml.CacheConfigImpl.checkInitializedState (CacheConfigImpl.java:620)
at org.apache.maven.buildcache.xml.CacheConfigImpl.getDefaultGlob (CacheConfigImpl.java:382)
at org.apache.maven.buildcache.checksum.MavenProjectInput. (MavenProjectInput.java:164)
at org.apache.maven.buildcache.DefaultProjectInputCalculator.calculateInputInternal (DefaultProjectInputCalculator.java:103)
at org.apache.maven.buildcache.DefaultProjectInputCalculator.calculateInput (DefaultProjectInputCalculator.java:89)
at org.apache.maven.buildcache.CacheControllerImpl.findCachedBuild (CacheControllerImpl.java:180)
at org.apache.maven.buildcache.BuildCacheMojosExecutionStrategy.execute (BuildCacheMojosExecutionStrategy.java:128)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:159)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:105)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:73)
at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build (SingleThreadedBuilder.java:53)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:118)
at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:261)
at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:173)
at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:101)
at org.apache.maven.cli.MavenCli.execute (MavenCli.java:906)
at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:283)
at org.apache.maven.cli.MavenCli.main (MavenCli.java:206)
at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)
at jdk.internal.reflect.NativeMethodAccessorImpl.invoke (NativeMethodAccessorImpl.java:77)
at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke (DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke (Method.java:568)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:255)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:201)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:361)
at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:314)
at org.codehaus.classworlds.Launcher.main (Launcher.java:41)
I have attached a trivial maven project to reproduce the problem.
I think I have located the source of the problem and could provide a PR for that.

untitled.zip

[khmarbaise]

Based on the given example project it can be reproduced just by trying to build the given project with this:

mvn -Dmaven.build.cache.enabled=false verify