fix #1161: Add error prone LoggerEnclosingClass

README.md

@@ -186,6 +186,7 @@ Safe Logging can be found at [github.com/palantir/safe-logging](https://github.c
 - `UnsafeGaugeRegistration`: Use TaggedMetricRegistry.registerWithReplacement over TaggedMetricRegistry.gauge.
 - `BracesRequired`: Require braces for loops and if expressions.
 - `CollectionStreamForEach`: Collection.forEach is more efficient than Collection.stream().forEach.
+- `LoggerEnclosingClass`: Loggers created using getLogger(Class<?>) must reference their enclosing class.
 
 ### Programmatic Application
 

baseline-error-prone/src/main/java/com/palantir/baseline/errorprone/LoggerEnclosingClass.java

@@ -0,0 +1,96 @@
+/*
+ * (c) Copyright 2020 Palantir Technologies Inc. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.palantir.baseline.errorprone;
+
+import com.google.auto.service.AutoService;
+import com.google.errorprone.BugPattern;
+import com.google.errorprone.VisitorState;
+import com.google.errorprone.bugpatterns.BugChecker;
+import com.google.errorprone.fixes.SuggestedFix;
+import com.google.errorprone.fixes.SuggestedFixes;
+import com.google.errorprone.matchers.Description;
+import com.google.errorprone.matchers.Matcher;
+import com.google.errorprone.matchers.Matchers;
+import com.google.errorprone.matchers.method.MethodMatchers;
+import com.google.errorprone.util.ASTHelpers;
+import com.sun.source.tree.ExpressionTree;
+import com.sun.source.tree.MemberSelectTree;
+import com.sun.source.tree.MethodInvocationTree;
+import com.sun.source.tree.Tree;
+import com.sun.source.tree.VariableTree;
+import com.sun.tools.javac.code.Symbol;
+
+@AutoService(BugChecker.class)
+@BugPattern(
+        name = "LoggerEnclosingClass",
+        link = "https://github.com/palantir/gradle-baseline#baseline-error-prone-checks",
+        linkType = BugPattern.LinkType.CUSTOM,
+        providesFix = BugPattern.ProvidesFix.REQUIRES_HUMAN_ATTENTION,
+        severity = BugPattern.SeverityLevel.WARNING,
+        summary = "Loggers created using getLogger(Class<?>) must reference their enclosing class.")
+public final class LoggerEnclosingClass extends BugChecker implements BugChecker.VariableTreeMatcher {
+
+    private static final Matcher<ExpressionTree> getLoggerMatcher = MethodMatchers.staticMethod()
+            .onClass("org.slf4j.LoggerFactory")
+            .named("getLogger")
+            // Only match the 'class' constructor
+            .withParameters(Class.class.getName());
+
+    private static final Matcher<VariableTree> fieldMatcher = Matchers.isField();
+
+    @Override
+    public Description matchVariable(VariableTree tree, VisitorState state) {
+        if (!fieldMatcher.matches(tree, state)) {
+            return Description.NO_MATCH;
+        }
+        ExpressionTree initializer = tree.getInitializer();
+        if (initializer == null) {
+            return Description.NO_MATCH;
+        }
+        if (!getLoggerMatcher.matches(initializer, state)) {
+            return Description.NO_MATCH;
+        }
+
+        MethodInvocationTree getLoggerInvocation = (MethodInvocationTree) initializer;
+        ExpressionTree classArgument = getLoggerInvocation.getArguments().get(0);
+
+        if (!(classArgument instanceof MemberSelectTree)) {
+            return Description.NO_MATCH;
+        }
+        MemberSelectTree memberSelectTree = (MemberSelectTree) classArgument;
+        if (!memberSelectTree.getIdentifier().contentEquals("class")
+                || memberSelectTree.getExpression().getKind() != Tree.Kind.IDENTIFIER) {
+            return Description.NO_MATCH;
+        }
+
+        Symbol targetSymbol = ASTHelpers.getSymbol(memberSelectTree.getExpression());
+        Symbol.ClassSymbol enclosingClassSymbol = ASTHelpers.enclosingClass(ASTHelpers.getSymbol(tree));
+        if (targetSymbol == null || enclosingClassSymbol == null) {
+            return Description.NO_MATCH;
+        }
+        if (state.getTypes().isSameType(targetSymbol.type, enclosingClassSymbol.type)) {
+            return Description.NO_MATCH;
+        }
+        SuggestedFix.Builder fix = SuggestedFix.builder();
+        return buildDescription(classArgument)
+                .addFix(fix.replace(
+                        classArgument,
+                        SuggestedFixes.prettyType(state, fix, enclosingClassSymbol.type) + ".class")
+                        .build())
+                .build();
+    }
+}

baseline-error-prone/src/test/java/com/palantir/baseline/errorprone/LoggerEnclosingClassTest.java

@@ -0,0 +1,63 @@
+/*
+ * (c) Copyright 2020 Palantir Technologies Inc. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.palantir.baseline.errorprone;
+
+import org.junit.jupiter.api.Test;
+
+class LoggerEnclosingClassTest {
+
+    @Test
+    void testFix() {
+        fix().addInputLines(
+                "Test.java",
+                "import org.slf4j.*;",
+                "class Test {",
+                "    private static final Logger log = LoggerFactory.getLogger(String.class);",
+                "}")
+                .addOutputLines(
+                        "Test.java",
+                        "import org.slf4j.*;",
+                        "class Test {",
+                        "    private static final Logger log = LoggerFactory.getLogger(Test.class);",
+                        "}")
+                .doTest();
+    }
+
+    @Test
+    void testNegative() {
+        fix().addInputLines(
+                "Test.java",
+                "import org.slf4j.*;",
+                "class Test {",
+                // Not great, but it's out of scope for this check to validate dynamic cases.
+                "    private static final Logger log = LoggerFactory.getLogger(dynamic());",
+                "    private static Class<String> dynamic() {",
+                "        return String.class;",
+                "    }",
+                "    private static void func() {",
+                "        LoggerFactory.getLogger(String.class);",
+                "        Logger local = LoggerFactory.getLogger(String.class);",
+                "    }",
+                "}")
+                .expectUnchanged()
+                .doTest();
+    }
+
+    private RefactoringValidator fix() {
+        return RefactoringValidator.of(new LoggerEnclosingClass(), getClass());
+    }
+}

changelog/@unreleased/pr-1163.v2.yml

@@ -0,0 +1,6 @@
+type: improvement
+improvement:
+  description: Add error prone LoggerEnclosingClass check. Loggers created using getLogger(Class<?>)
+    must reference their enclosing class.
+  links:
+  - https://github.com/palantir/gradle-baseline/pull/1163

gradle-baseline-java/src/main/groovy/com/palantir/baseline/extensions/BaselineErrorProneExtension.java

@@ -31,6 +31,7 @@ public class BaselineErrorProneExtension {
             "ExecutorSubmitRunnableFutureIgnored",
             "FinalClass",
             "LambdaMethodReference",
+            "LoggerEnclosingClass",
             "OptionalOrElseMethodInvocation",
             "PreferBuiltInConcurrentKeySet",
             "PreferCollectionTransform",