Fix IllegalResolutionException in UnusedDependencyExcludeRule for Gradle 9.x (#437)

Author: rpalcolea

src/main/groovy/com/netflix/nebula/lint/rule/dependency/UnusedDependencyExcludeRule.groovy

@@ -20,8 +20,6 @@ import com.netflix.nebula.lint.rule.GradleAstUtil
 import com.netflix.nebula.lint.rule.GradleDependency
 import com.netflix.nebula.lint.rule.ModelAwareGradleLintRule
 import org.codehaus.groovy.ast.expr.MethodCallExpression
-import org.gradle.api.artifacts.Configuration
-import org.gradle.api.specs.Specs
 
 class UnusedDependencyExcludeRule extends ModelAwareGradleLintRule {
     String description = 'excludes that have no effect on the classpath should be removed for clarity'
@@ -51,28 +49,29 @@ class UnusedDependencyExcludeRule extends ModelAwareGradleLintRule {
     }
 
     private boolean isExcludeUnnecessary(String group, String name) {
-        // Since Gradle does not expose any information about which excludes were effective, we will create a new configuration
-        // lintExcludeConf, add the dependency and resolve it.
-        Configuration lintExcludeConf = project.configurations.create("lintExcludes")
-        project.dependencies.add(lintExcludeConf.name, "$dependency.group:$dependency.name:$dependency.version")
+        // Use detached configurations instead of project configurations to avoid threading issues
+        // in Gradle 9.x which requires exclusive locks for configuration resolution
+        def detachedConf = project.configurations.detachedConfiguration(
+            project.dependencies.create("$dependency.group:$dependency.name:$dependency.version")
+        )
 
-        // If we find a dependency in the transitive closure of this special conf, then we can infer that the exclusion is
-        // doing something. Note that all*.exclude style exclusions are applied to all of the configurations at the time
-        // of project evaluation, but not lintExcludeConf.
+        // This is thread-safe and doesn't require exclusive locks
+        def resolutionResult = detachedConf.incoming.resolutionResult
+        
         def excludeIsInTransitiveClosure = false
-        def deps = lintExcludeConf.resolvedConfiguration.lenientConfiguration.getFirstLevelModuleDependencies()
-        while(!deps.isEmpty() && !excludeIsInTransitiveClosure) {
-            deps = deps.collect { d ->
-                if((!group || d.moduleGroup == group) && (!name || d.moduleName == name)) {
-                    excludeIsInTransitiveClosure = true
-                }
-                d.children
+        
+        def allComponents = resolutionResult.allComponents
+        
+        for (component in allComponents) {
+            def moduleVersion = component.moduleVersion
+            if (moduleVersion && 
+                (!group || moduleVersion.group == group) && 
+                (!name || moduleVersion.name == name)) {
+                excludeIsInTransitiveClosure = true
+                break
             }
-            .flatten()
         }
-
-        project.configurations.remove(lintExcludeConf)
-
-        !excludeIsInTransitiveClosure
+        
+        return !excludeIsInTransitiveClosure
     }
 }

src/test/groovy/com/netflix/nebula/lint/rule/dependency/UnusedDependencyExcludeRuleSpec.groovy

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2019 Netflix, Inc.
+ * Copyright 2015-2025 Netflix, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,7 +28,6 @@ class UnusedDependencyExcludeRuleSpec extends AbstractRuleSpec {
 
     def 'unused exclude violates'() {
         when:
-        // trivial case: no dependencies
         project.buildFile << """
             apply plugin: 'java'
             dependencies {
@@ -58,7 +57,6 @@ class UnusedDependencyExcludeRuleSpec extends AbstractRuleSpec {
 
     def 'unused exclude violates - api configuration'() {
         when:
-        // trivial case: no dependencies
         project.buildFile << """
             apply plugin: 'java-library'
             dependencies {
@@ -89,7 +87,7 @@ class UnusedDependencyExcludeRuleSpec extends AbstractRuleSpec {
 
     def 'exclude matching a transitive dependency does not violate'() {
         when:
-        // trivial case: no dependencies
+
         project.buildFile << """
             apply plugin: 'java'
             dependencies {
@@ -120,7 +118,6 @@ class UnusedDependencyExcludeRuleSpec extends AbstractRuleSpec {
     @Issue('#57')
     def 'exclude on a dependency that is unresolvable is considered unapplicable'() {
         when:
-        // trivial case: no dependencies
         project.buildFile << """
             apply plugin: 'java'
             dependencies {
@@ -147,4 +144,203 @@ class UnusedDependencyExcludeRuleSpec extends AbstractRuleSpec {
         then:
         results.violates()
     }
+
+    def 'detects multiple unused excludes on same dependency'() {
+        when:
+        project.buildFile << """
+            apply plugin: 'java'
+            dependencies {
+                implementation('commons-configuration:commons-configuration:1.10') {
+                    exclude group: 'com.google.guava', module: 'guava'
+                    exclude group: 'com.fasterxml.jackson.core', module: 'jackson-core'
+                    exclude group: 'commons-lang', module: 'commons-lang'
+                }
+            }
+        """
+
+        project.with {
+            apply plugin: 'java'
+            repositories {
+                mavenCentral()
+            }
+            dependencies {
+                implementation('commons-configuration:commons-configuration:1.10') {
+                    exclude group: 'com.google.guava', module: 'guava'
+                    exclude group: 'com.fasterxml.jackson.core', module: 'jackson-core'
+                    exclude group: 'commons-lang', module: 'commons-lang'
+                }
+            }
+        }
+
+        def results = runRulesAgainst(rule)
+
+        then:
+        results.violates()
+
+        results.violations.size() == 2
+        results.violations.any { it.message.contains('the excluded dependency is not a transitive') && it.sourceLine.contains('com.google.guava') }
+        results.violations.any { it.message.contains('the excluded dependency is not a transitive') && it.sourceLine.contains('com.fasterxml.jackson.core') }
+        !results.violations.any { it.sourceLine.contains('commons-lang') && it.sourceLine.contains('commons-lang') }
+    }
+
+    def 'works with testImplementation configuration'() {
+        when:
+        project.buildFile << """
+            apply plugin: 'java'
+            dependencies {
+                testImplementation('junit:junit:4.13.2') {
+                    exclude group: 'fake.group', module: 'fake-module'
+                }
+            }
+        """
+
+        project.with {
+            apply plugin: 'java'
+            repositories {
+                mavenCentral()
+            }
+            dependencies {
+                testImplementation('junit:junit:4.13.2') {
+                    exclude group: 'fake.group', module: 'fake-module'
+                }
+            }
+        }
+
+        def results = runRulesAgainst(rule)
+
+        then:
+        results.violates()
+        results.violations[0].message.contains('the excluded dependency is not a transitive')
+        results.violations[0].sourceLine.contains('fake.group') && results.violations[0].sourceLine.contains('fake-module')
+    }
+
+    def 'handles exclude with only group specified'() {
+        when:
+        project.buildFile << """
+            apply plugin: 'java'
+            dependencies {
+                implementation('commons-configuration:commons-configuration:1.10') {
+                    exclude group: 'com.google.guava'
+                }
+            }
+        """
+
+        project.with {
+            apply plugin: 'java'
+            repositories {
+                mavenCentral()
+            }
+            dependencies {
+                implementation('commons-configuration:commons-configuration:1.10') {
+                    exclude group: 'com.google.guava'
+                }
+            }
+        }
+
+        def results = runRulesAgainst(rule)
+
+        then:
+        results.violates()
+        results.violations[0].message.contains('the excluded dependency is not a transitive')
+    }
+
+    def 'handles exclude with only module specified'() {
+        when:
+        project.buildFile << """
+            apply plugin: 'java'
+            dependencies {
+                implementation('commons-configuration:commons-configuration:1.10') {
+                    exclude module: 'guava'
+                }
+            }
+        """
+
+        project.with {
+            apply plugin: 'java'
+            repositories {
+                mavenCentral()
+            }
+            dependencies {
+                implementation('commons-configuration:commons-configuration:1.10') {
+                    exclude module: 'guava'
+                }
+            }
+        }
+
+        def results = runRulesAgainst(rule)
+
+        then:
+        results.violates()
+        results.violations[0].message.contains('the excluded dependency is not a transitive')
+    }
+
+    @Issue('Gradle 9.x compatibility - detached configurations')
+    def 'rule creates and cleans up configurations properly'() {
+        when:
+        project.buildFile << """
+            apply plugin: 'java'
+            dependencies {
+                implementation('commons-configuration:commons-configuration:1.10') {
+                    exclude group: 'com.google.guava', module: 'guava'
+                }
+            }
+        """
+
+        project.with {
+            apply plugin: 'java'
+            repositories {
+                mavenCentral()
+            }
+            dependencies {
+                implementation('commons-configuration:commons-configuration:1.10') {
+                    exclude group: 'com.google.guava', module: 'guava'
+                }
+            }
+        }
+
+        def configurationsBefore = project.configurations.collect { it.name }
+        def results = runRulesAgainst(rule)
+        def configurationsAfter = project.configurations.collect { it.name }
+
+        then:
+        results.violates()
+        configurationsBefore == configurationsAfter
+        !configurationsAfter.any { it.contains('lintExcludes') }
+    }
+
+    def 'handles complex dependency with multiple transitives'() {
+        when:
+        project.buildFile << """
+            apply plugin: 'java'
+            dependencies {
+                implementation('org.springframework:spring-web:5.3.0') {
+                    exclude group: 'org.springframework', module: 'spring-core' // valid
+                    exclude group: 'fake.spring', module: 'fake-spring-core' // invalid
+                }
+            }
+        """
+
+        project.with {
+            apply plugin: 'java'
+            repositories {
+                mavenCentral()
+            }
+            dependencies {
+                implementation('org.springframework:spring-web:5.3.0') {
+                    exclude group: 'org.springframework', module: 'spring-core'
+                    exclude group: 'fake.spring', module: 'fake-spring-core'
+                }
+            }
+        }
+
+        def results = runRulesAgainst(rule)
+
+        then:
+        results.violates()
+
+        results.violations.size() == 1
+        results.violations[0].message.contains('the excluded dependency is not a transitive')
+        results.violations[0].sourceLine.contains('fake.spring') && results.violations[0].sourceLine.contains('fake-spring-core')
+        !results.violations.any { it.sourceLine.contains('spring-core') && !it.sourceLine.contains('fake') }
+    }
 }