Short circuit lint tasks on projects that have no physical build.gradle

Author: jkschneider

src/integTest/java/com/netflix/nebula/lint/plugin/GradleLintPluginSpec.groovy

@@ -31,6 +31,22 @@ class GradleLintPluginSpec extends IntegrationSpec {
         console.any { it.contains('dependency-tuple') }
     }
 
+    def 'run rules on multi-module project where one of the subprojects has no build.gradle'() {
+        when:
+        buildFile << """
+            allprojects {
+                apply plugin: 'java'
+                apply plugin: ${GradleLintPlugin.name}
+                gradleLint.rules = ['dependency-parentheses', 'dependency-tuple']
+            }
+        """
+
+        addSubproject('sub')
+
+        then:
+        runTasksSuccessfully('gradleLint')
+    }
+
     def 'auto correct all violations on a single module project'() {
         when:
         buildFile << """

src/main/groovy/com/netflix/nebula/lint/plugin/GradleLintCorrectionTask.groovy

@@ -19,6 +19,10 @@ class GradleLintCorrectionTask extends DefaultTask {
 
     @TaskAction
     void lintCorrections() {
+        if(!project.buildFile.exists()) {
+            return
+        }
+
         def registry = new LintRuleRegistry(project)
         def ruleSet = RuleSetFactory.configureRuleSet(project.extensions
                 .getByType(GradleLintExtension)

src/main/groovy/com/netflix/nebula/lint/plugin/GradleLintReportTask.groovy

@@ -35,6 +35,10 @@ class GradleLintReportTask extends DefaultTask implements VerificationTask, Repo
 
     @TaskAction
     void generateReport() {
+        if(!project.buildFile.exists()) {
+            return
+        }
+
         if(reports.enabled) {
             def lintExt = project.extensions.getByType(GradleLintExtension)
             def registry = new LintRuleRegistry(project)

src/main/groovy/com/netflix/nebula/lint/plugin/GradleLintTask.groovy

@@ -18,15 +18,19 @@ class GradleLintTask extends DefaultTask {
 
     @TaskAction
     void lint() {
+        if(!project.buildFile.exists()) {
+            return
+        }
+
         def textOutput = textOutputFactory.create('lint')
         def buildFilePath = relPath(project.rootDir, project.buildFile).path
 
         def registry = new LintRuleRegistry(project)
-        def ruleSet = RuleSetFactory.configureRuleSet(project
+        def extension = project
                 .extensions
                 .getByType(GradleLintExtension)
-                .rules
-                .collect { registry.buildRules(it) }
+
+        def ruleSet = RuleSetFactory.configureRuleSet(extension.rules.collect { registry.buildRules(it) }
                 .flatten() as List<Rule>)
 
         def violations = new StringSourceAnalyzer(project.buildFile.text).analyze(ruleSet).violations