Revert "Strict unused variable enforces lambda parameters (#1355)"

This reverts commit 620c65b.
palantir · May 28, 2020 · b817a1e · b817a1e
1 parent 26a93df
commit b817a1e
Show file tree

Hide file tree

Showing 2 changed files with 5 additions and 80 deletions.
diff --git a/...line-error-prone/src/main/java/com/palantir/baseline/errorprone/StrictUnusedVariable.java b/...line-error-prone/src/main/java/com/palantir/baseline/errorprone/StrictUnusedVariable.java
@@ -51,7 +51,6 @@
 import com.google.auto.service.AutoService;
 import com.google.common.base.Ascii;
 import com.google.common.base.CaseFormat;
-import com.google.common.base.Preconditions;
 import com.google.common.collect.ArrayListMultimap;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableListMultimap;
@@ -221,15 +220,7 @@ public Description matchCompilationUnit(CompilationUnitTree tree, VisitorState s
             Symbol.VarSymbol symbol = (Symbol.VarSymbol) unusedSymbol;
             ImmutableList<SuggestedFix> fixes;
             if (symbol.getKind() == ElementKind.PARAMETER && !isEverUsed.contains(unusedSymbol)) {
-                Symbol.MethodSymbol methodSymbol = (Symbol.MethodSymbol) symbol.owner;
-                int index = methodSymbol.params.indexOf(symbol);
-                // If we can not find the parameter in the owning method, then it must be a parameter to a lambda
-                // defined within the method
-                if (index == -1) {
-                    fixes = buildUnusedLambdaParameterFix(symbol, entry.getValue(), state);
-                } else {
-                    fixes = buildUnusedParameterFixes(symbol, methodSymbol, allUsageSites, state);
-                }
+                fixes = buildUnusedParameterFixes(symbol, allUsageSites, state);
             } else {
                 fixes = buildUnusedVarFixes(symbol, allUsageSites, state);
             }
@@ -481,34 +472,11 @@ private static ImmutableList<SuggestedFix> buildUnusedVarFixes(
         return ImmutableList.of(fix.build());
     }
 
-    private static ImmutableList<SuggestedFix> buildUnusedLambdaParameterFix(
-            Symbol.VarSymbol _symbol, Collection<UnusedSpec> values, VisitorState state) {
-        SuggestedFix.Builder fix = SuggestedFix.builder();
-
-        for (UnusedSpec unusedSpec : values) {
-            Tree leaf = unusedSpec.variableTree().getLeaf();
-            if (!(leaf instanceof VariableTree)) {
-                continue;
-            }
-
-            VariableTree tree = (VariableTree) leaf;
-            if (state.getEndPosition(tree.getType()) == -1) {
-                fix.replace(tree, "_" + tree.getName());
-            } else {
-                int startPos = state.getEndPosition(tree.getType()) + 1;
-                int endPos = state.getEndPosition(tree);
-                fix.replace(startPos, endPos, "_" + tree.getName());
-            }
-        }
-
-        return ImmutableList.of(fix.build());
-    }
-
     private static ImmutableList<SuggestedFix> buildUnusedParameterFixes(
-            Symbol varSymbol, Symbol.MethodSymbol methodSymbol, List<TreePath> usagePaths, VisitorState state) {
+            Symbol varSymbol, List<TreePath> usagePaths, VisitorState state) {
+        Symbol.MethodSymbol methodSymbol = (Symbol.MethodSymbol) varSymbol.owner;
         boolean isPrivateMethod = methodSymbol.getModifiers().contains(Modifier.PRIVATE);
         int index = methodSymbol.params.indexOf(varSymbol);
-        Preconditions.checkState(index != -1, "symbol %s must be a parameter to the owning method", varSymbol);
         SuggestedFix.Builder fix = SuggestedFix.builder();
         for (TreePath path : usagePaths) {
             fix.delete(path.getLeaf());
@@ -748,9 +716,8 @@ public Void visitClass(ClassTree tree, Void unused) {
 
         @Override
         public Void visitLambdaExpression(LambdaExpressionTree node, Void unused) {
-            scan(node.getBody(), null);
-            scan(node.getParameters(), null);
-            return null;
+            // skip lambda parameters
+            return scan(node.getBody(), null);
         }
 
         @Override

diff --git a/...-error-prone/src/test/java/com/palantir/baseline/errorprone/StrictUnusedVariableTest.java b/...-error-prone/src/test/java/com/palantir/baseline/errorprone/StrictUnusedVariableTest.java
@@ -95,24 +95,6 @@ public void handles_enums() {
                 .doTest();
     }
 
-    @Test
-    void handles_lambdas() {
-        compilationHelper
-                .addSourceLines(
-                        "Test.java",
-                        "import java.util.function.BiFunction;",
-                        "import java.util.Optional;",
-                        "class Test {",
-                        "  private static BiFunction<String, String, Integer> doStuff() {",
-                        "  // BUG: Diagnostic contains: Unused",
-                        "    BiFunction<String, String, Integer> first = (String value1, String value2) -> 1;",
-                        "  // BUG: Diagnostic contains: Unused",
-                        "    return first.andThen(value3 -> 2);",
-                        "  }",
-                        "}")
-                .doTest();
-    }
-
     @Test
     public void renames_previous_suppression() {
         refactoringTestHelper
@@ -151,30 +133,6 @@ public void renames_unused_param() {
                 .doTest(TestMode.TEXT_MATCH);
     }
 
-    @Test
-    void renames_unused_lambda_params() {
-        refactoringTestHelper
-                .addInputLines(
-                        "Test.java",
-                        "import java.util.function.BiFunction;",
-                        "class Test {",
-                        "  private static BiFunction<String, String, Integer> doStuff() {",
-                        "    BiFunction<String, String, Integer> first = (String value1, String value2) -> 1;",
-                        "    return first.andThen(value3 -> 2);",
-                        "  }",
-                        "}")
-                .addOutputLines(
-                        "Test.java",
-                        "import java.util.function.BiFunction;",
-                        "class Test {",
-                        "  private static BiFunction<String, String, Integer> doStuff() {",
-                        "    BiFunction<String, String, Integer> first = (String _value1, String _value2) -> 1;",
-                        "    return first.andThen(_value3 -> 2);",
-                        "  }",
-                        "}")
-                .doTest();
-    }
-
     @Test
     public void fails_suppressed_but_used_variables() {
         compilationHelper