[Codenarc-user] Running rules which require compilerPhase > Phases.CONVERSION using Gradle's CodeNarc plugin

[Marcin E. <mar...@pr...>]

Hi,

I wrote a custom rule which requires SEMANTIC_ANALYSIS compiler phase and
I'm trying to run it using Gradle. Unfortunately I'm getting compilation
errors upon analysis telling me that compiler cannot load any of the
classes imported by the analysed code, even though I checked and they are
available in the codenarc configuration of my project which is added by
Gradle's CodeNarc plugin and used to load CodeNarc classes, see:

-
https://github.com/gradle/gradle/blob/v3.3.0/subprojects/code-quality/src/main/groovy/org/gradle/api/plugins/quality/CodeNarcPlugin.java#L72
-
https://github.com/gradle/gradle/blob/v3.3.0/subprojects/code-quality/src/main/groovy/org/gradle/api/plugins/quality/CodeNarcPlugin.java#L89
-
https://github.com/gradle/gradle/blob/v3.3.0/subprojects/code-quality/src/main/groovy/org/gradle/api/plugins/quality/CodeNarc.java#L104
-
https://github.com/gradle/gradle/blob/v3.3.0/subprojects/code-quality/src/main/groovy/org/gradle/api/plugins/quality/internal/CodeNarcInvoker.groovy#L45

I then dug around and realised that when CodeNarc compiles analysed code it
uses the context class loader, see:
-
https://github.com/CodeNarc/CodeNarc/blob/v0.26.0/src/main/groovy/org/codenarc/source/AbstractSourceCode.groovy#L88
-
https://github.com/groovy/groovy-core/blob/GROOVY_2_1_8/src/main/org/codehaus/groovy/control/CompilationUnit.java#L94
https://github.com/groovy/groovy-core/blob/GROOVY_2_1_8/src/main/org/codehaus/groovy/control/CompilationUnit.java#L136
-
https://github.com/groovy/groovy-core/blob/GROOVY_2_1_8/src/main/org/codehaus/groovy/control/ProcessingUnit.java#L64
-
https://github.com/groovy/groovy-core/blob/GROOVY_2_1_8/src/main/org/codehaus/groovy/control/ProcessingUnit.java#L103

And I finally realised that Gradle's BasicAntBuilder replaces the context
class loader to only contain Ant classes which means that not even Groovy
classes are available on the compilation classpath when CodeNarc compiles
the analysed code:
-
https://github.com/gradle/gradle/blob/v3.3.0/subprojects/code-quality/src/main/groovy/org/gradle/api/plugins/quality/internal/CodeNarcInvoker.groovy#L45
-
https://github.com/gradle/gradle/blob/v3.3.0/subprojects/core/src/main/java/org/gradle/api/internal/project/antbuilder/DefaultIsolatedAntBuilder.java#L151
-
https://github.com/gradle/gradle/blob/v3.3.0/subprojects/core/src/main/java/org/gradle/api/internal/project/ant/BasicAntBuilder.java#L76

Given the above, here are my questions:

1. Has anybody ever managed to get their projects set up correctly and get
violations for one of the built-in CodeNarc Enhanced Classpath Rules,
e.g. CloneWithoutCloneable? If that's the case can they please explain how
they achieved it? If one is to believe comments in Gradle's codebase (e.g.
https://github.com/gradle/gradle/blob/v3.3.0/subprojects/core/src/main/java/org/gradle/api/internal/project/antbuilder/DefaultIsolatedAntBuilder.java#L140)
then it looks like a similar problem to the one occurring when using Gradle
would occur when using Ant.

2. Is there a reason for CodeNarc to use the context class loader instead
of the class loader that loaded CodeNarc when compiling the analysed code?
Given that it is a breaking change, would a PR changing that class loader
to the one which loaded CodeNarc be a valid option? It is a breaking change
but I don't see a reason why somebody would depend on current behaviour as
it actually prevents usage of Enhanced Classpath Rules. Or should I look
into changing Gradle's CodeNarc plugin to set the context class loader as
per CodeNarc's expectations?

Cheers,
Marcin