Fix grails-plugin.xml generation and importJavaTime setting (#388)

* fix: set default `importJavaTime` value to `false`

The `importJavaTime` setting modifies the import behavior for Java Date/Time classes by applying a config script to the Groovy compiler. This causes issues in Grails plugins, as the config script interferes with the generation of the `META-INF/grails-plugin.xml` file.

By defaulting `importJavaTime` to `false`, these issues are avoided until a more robust solution can be implemented.

* fix: honor the `importJavaTime` setting

This fix addresses a problem where the `importJavaTime` setting was not honored as it was used in the evaluation phase, before the project got a chance to change it.

* build: add the `grails-bom`

The `grails-bom` is no longer an `api` dependency in `grails-core`.

* fix: support multiple compiler configs to be merged

This commit will enable more than one compiler configuration to be used by merging them. It will also merge the compiler configs for generating `grails-plugin.xml` and importing Java Date/Time.

build.gradle

@@ -75,6 +75,8 @@ java {
 }
 
 dependencies {
+    implementation platform("org.grails:grails-bom:$grailsVersion")
+
     // compile grails-gradle-plugin with the Groovy version provided by Gradle
     // to ensure build compatibility with Gradle, currently Groovy 3.0.x
     // see: https://docs.gradle.org/current/userguide/compatibility.html#groovy

src/main/groovy/org/grails/gradle/plugin/core/GrailsExtension.groovy

@@ -60,7 +60,7 @@ class GrailsExtension {
     /**
      * Whether java.time.* package should be a default import package
      */
-    boolean importJavaTime = true
+    boolean importJavaTime = false
 
     /**
      * Configure the reloading agent

src/main/groovy/org/grails/gradle/plugin/core/GrailsGradlePlugin.groovy

@@ -143,6 +143,16 @@ class GrailsGradlePlugin extends GroovyPlugin {
         configureRunCommand(project)
 
         configurePathingJar(project)
+
+        def configScriptTask = project.tasks.create('configScript')
+        def configFile = project.layout.buildDirectory.file('config.groovy')
+        configScriptTask.outputs.file(configFile)
+        addJavaTimeImport(project, configScriptTask)
+
+        project.tasks.withType(GroovyCompile).configureEach { GroovyCompile task ->
+            task.dependsOn('configScript')
+            task.groovyOptions.configurationScript = project.tasks.named('configScript').get().outputs.files.singleFile
+        }
     }
 
     protected void excludeDependencies(Project project) {
@@ -289,26 +299,19 @@ class GrailsGradlePlugin extends GroovyPlugin {
                 }
             }
         }
+    }
 
-        GrailsExtension grailsExt = project.extensions.getByType(GrailsExtension)
-        project.tasks.withType(GroovyCompile).configureEach { groovyCompileTask ->
+    protected void addJavaTimeImport(Project project, Task configScriptTask) {
+        configScriptTask.doLast {
+            GrailsExtension grailsExt = project.extensions.getByType(GrailsExtension)
             if (grailsExt.importJavaTime) {
-                groovyCompileTask.doFirst {
-                    def configScriptStream = getClass().getResourceAsStream("/GrailsCompilerConfig.groovy")
-                    if (configScriptStream != null) {
-                        def tempConfigScriptFile = File.createTempFile("build/GrailsCompilerConfig", ".groovy")
-                        tempConfigScriptFile.mkdirs()
-                        tempConfigScriptFile.deleteOnExit()
-
-                        def existingScript = groovyCompileTask.groovyOptions.configurationScript
-                        if (existingScript) {
-                            tempConfigScriptFile << existingScript.text
-                        }
-
-                        tempConfigScriptFile.text = configScriptStream.text
-                        groovyCompileTask.groovyOptions.configurationScript = tempConfigScriptFile
-                    }
+                outputs.files.singleFile << '''
+                configuration.with {
+                    def importCustomizer = new org.codehaus.groovy.control.customizers.ImportCustomizer()
+                    importCustomizer.addStarImports('java.time')
+                    addCompilationCustomizers(importCustomizer)
                 }
+                '''.stripIndent(16)
             }
         }
     }

src/main/groovy/org/grails/gradle/plugin/core/GrailsPluginGradlePlugin.groovy

@@ -256,32 +256,22 @@ class GrailsPluginGradlePlugin extends GrailsGradlePlugin {
         }
     }
 
-    @CompileDynamic
     protected void configureProjectNameAndVersionASTMetadata(Project project) {
-        def configScriptTask = project.tasks.create('configScript')
-
-        def configFile = project.file("$project.buildDir/config.groovy")
-        configScriptTask.outputs.file(configFile)
-
         def projectName = project.name
         def projectVersion = project.version
+        def configScriptTask = project.tasks.named('configScript').get()
         configScriptTask.inputs.property('name', projectName)
         configScriptTask.inputs.property('version', projectVersion)
         configScriptTask.doLast {
-            configFile.parentFile.mkdirs()
-            configFile.text = """
-withConfig(configuration) {
-    inline(phase: 'CONVERSION') { source, context, classNode ->
-        classNode.putNodeMetaData('projectVersion', '$projectVersion')
-        classNode.putNodeMetaData('projectName', '$projectName')
-        classNode.putNodeMetaData('isPlugin', 'true')
-    }
-}
-"""
-        }
-        project.tasks.getByName('compileGroovy').dependsOn(configScriptTask)
-        project.compileGroovy {
-            groovyOptions.configurationScript = configFile
+            outputs.files.singleFile << """
+            withConfig(configuration) {
+                inline(phase: 'CONVERSION') { source, context, classNode ->
+                    classNode.putNodeMetaData('projectVersion', '$projectVersion')
+                    classNode.putNodeMetaData('projectName', '$projectName')
+                    classNode.putNodeMetaData('isPlugin', 'true')
+                }
+            }
+            """.stripIndent(12)
         }
     }