Fix some quality flaws

javascript-checks/src/main/java/org/sonar/javascript/checks/EqEqEqCheck.java

@@ -58,11 +58,7 @@ boolean isProblem(BinaryExpressionTree tree, ProgramState currentState) {
     Type rightType = rightConstraint.type();
     Type leftType = leftConstraint.type();
 
-    if (leftType != null && leftType == rightType) {
-      return true;
-    }
-
-    return false;
+    return leftType != null && leftType == rightType;
   }
 
 

javascript-checks/src/main/java/org/sonar/javascript/checks/ReassignedParameterCheck.java

@@ -20,7 +20,6 @@
 package org.sonar.javascript.checks;
 
 import com.google.common.collect.ImmutableSet;
-import java.util.Optional;
 import java.util.Set;
 import javax.annotation.Nullable;
 import org.sonar.check.Rule;
@@ -84,30 +83,26 @@ private void checkForLoop(ForObjectStatementTree forLoop) {
 
     } else if (variableOrExpression.is(Kind.IDENTIFIER_REFERENCE)) {
       IdentifierTree identifier = (IdentifierTree) variableOrExpression;
-      checkSymbol(identifier.symbol(), identifier, forLoop, FOREACH_VARIABLE);
-
+      identifier.symbol().ifPresent(s -> checkSymbol(s, identifier, forLoop, FOREACH_VARIABLE));
     }
   }
 
   private void checkBindingElement(BindingElementTree parameter, String title) {
     for (IdentifierTree identifierTree : parameter.bindingIdentifiers()) {
       // symbol for identifier from binding element should never be null
-      checkSymbol(identifierTree.symbol(), identifierTree, null, title);
+      identifierTree.symbol().ifPresent(s -> checkSymbol(s, identifierTree, null, title));
     }
   }
 
-  private void checkSymbol(Optional<Symbol> symbol, IdentifierTree declarationIdentifier, @Nullable ForObjectStatementTree loop, String title) {
-    if (!symbol.isPresent()) {
-      return;
-    }
+  private void checkSymbol(Symbol symbol, IdentifierTree declarationIdentifier, @Nullable ForObjectStatementTree loop, String title) {
 
-    for (Usage usage : symbol.get().usages()) {
+    for (Usage usage : symbol.usages()) {
 
       if (usage.isWrite() &&
         !usage.identifierTree().equals(declarationIdentifier)
         && (loop == null || CheckUtils.isDescendant(usage.identifierTree(), loop))) {
 
-        addIssue(usage.identifierTree(), String.format(MESSAGE, title, symbol.get().name()));
+        addIssue(usage.identifierTree(), String.format(MESSAGE, title, symbol.name()));
       }
     }
   }

javascript-checks/src/main/java/org/sonar/javascript/checks/UnconditionalJumpStatementCheck.java

@@ -69,7 +69,7 @@ public void visitNode(Tree tree) {
     }
   }
 
-  private boolean isInfiniteFor(IterationStatementTree loopTree) {
+  private static boolean isInfiniteFor(IterationStatementTree loopTree) {
     if (loopTree.is(Kind.FOR_STATEMENT)) {
       ForStatementTree forLoop = (ForStatementTree) loopTree;
       return forLoop.update() == null && forLoop.init() == null && forLoop.condition() == null;

javascript-frontend/src/main/java/org/sonar/javascript/metrics/CounterVisitor.java

@@ -20,7 +20,7 @@
 package org.sonar.javascript.metrics;
 
 import java.util.Arrays;
-import java.util.HashSet;
+import java.util.EnumSet;
 import java.util.Set;
 import org.sonar.javascript.tree.KindSet;
 import org.sonar.plugins.javascript.api.tree.Tree;
@@ -59,7 +59,7 @@ public CounterVisitor(Tree tree) {
 
   @Override
   public Set<Kind> nodesToVisit() {
-    HashSet<Kind> result = new HashSet<>(KindSet.FUNCTION_KINDS.getSubKinds());
+    Set<Kind> result = EnumSet.copyOf(KindSet.FUNCTION_KINDS.getSubKinds());
     result.addAll(Arrays.asList(STATEMENT_NODES));
     result.addAll(Arrays.asList(MetricsVisitor.getClassNodes()));
     return result;

javascript-frontend/src/main/java/org/sonar/javascript/metrics/MetricsVisitor.java

@@ -21,8 +21,8 @@
 
 import java.io.Serializable;
 import java.util.Arrays;
+import java.util.EnumSet;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
 import org.sonar.api.batch.fs.InputFile;
@@ -78,7 +78,7 @@ public Map<InputFile, Set<Integer>> executableLines() {
 
   @Override
   public Set<Kind> nodesToVisit() {
-    Set<Kind> result = new HashSet<>(KindSet.FUNCTION_KINDS.getSubKinds());
+    Set<Kind> result = EnumSet.copyOf(KindSet.FUNCTION_KINDS.getSubKinds());
     result.addAll(Arrays.asList(CLASS_NODES));
     return result;
   }

javascript-frontend/src/main/java/org/sonar/javascript/parser/TreeFactory.java

@@ -1127,7 +1127,10 @@ public SeparatedList<SpecifierTree> exportListBody(
   }
 
   public SpecifierListTree exportList(InternalSyntaxToken openCurlyBraceToken, Optional<SeparatedList<SpecifierTree>> specifierList, InternalSyntaxToken closeCurlyBraceToken) {
-    return new SpecifierListTreeImpl(Kind.EXPORT_LIST, openCurlyBraceToken, specifierList.or(new SeparatedListImpl<>(ImmutableList.of(), ImmutableList.of())), closeCurlyBraceToken);
+    return new SpecifierListTreeImpl(
+      Kind.EXPORT_LIST,
+      openCurlyBraceToken,
+      specifierList.or(new SeparatedListImpl<>(ImmutableList.of(), ImmutableList.of())), closeCurlyBraceToken);
   }
 
   public NameSpaceExportDeclarationTree namespaceExportDeclaration(
@@ -1216,7 +1219,10 @@ public SeparatedList<SpecifierTree> newImportSpecifierList(
   }
 
   public SpecifierListTree importList(InternalSyntaxToken openCurlyBraceToken, Optional<SeparatedList<SpecifierTree>> specifierList, InternalSyntaxToken closeCurlyBraceToken) {
-    return new SpecifierListTreeImpl(Kind.IMPORT_LIST, openCurlyBraceToken, specifierList.or(new SeparatedListImpl<>(ImmutableList.of(), ImmutableList.of())), closeCurlyBraceToken);
+    return new SpecifierListTreeImpl(
+      Kind.IMPORT_LIST,
+      openCurlyBraceToken,
+      specifierList.or(new SeparatedListImpl<>(ImmutableList.of(), ImmutableList.of())), closeCurlyBraceToken);
   }
 
   public SpecifierTree nameSpaceImport(InternalSyntaxToken starToken, InternalSyntaxToken asToken, IdentifierTree localName) {

javascript-frontend/src/main/java/org/sonar/javascript/se/LiveVariableAnalysis.java

@@ -27,7 +27,6 @@
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
-import java.util.Optional;
 import java.util.Set;
 import javax.annotation.CheckForNull;
 import javax.annotation.Nullable;
@@ -171,21 +170,19 @@ public boolean hasUsagesInNestedFunctions(Symbol symbol) {
 
     @CheckForNull
     private Usage add(IdentifierTree identifier) {
-      addSymbol(identifier.symbol());
+      identifier.symbol().ifPresent(s -> addSymbol(s));
       Usage usage = localVariableUsages.get(identifier);
       if (usage != null) {
         usagesInCFG.put(usage.symbol(), usage);
       }
       return usage;
     }
 
-    private void addSymbol(Optional<Symbol> symbolOptional) {
-      if (!symbolOptional.isPresent() || symbols.contains(symbolOptional.get())) {
+    private void addSymbol(Symbol symbol) {
+      if (symbols.contains(symbol)) {
         return;
       }
 
-      Symbol symbol = symbolOptional.get();
-
       symbols.add(symbol);
 
       if (isLocalVariable(symbol)) {

javascript-frontend/src/main/java/org/sonar/javascript/se/limitations/package-info.java

@@ -0,0 +1,21 @@
+/*
+ * SonarQube JavaScript Plugin
+ * Copyright (C) 2011-2017 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+@javax.annotation.ParametersAreNonnullByDefault
+package org.sonar.javascript.se.limitations;

javascript-frontend/src/main/java/org/sonar/javascript/tree/impl/declaration/ArrayBindingPatternTreeImpl.java

@@ -98,9 +98,7 @@ public List<IdentifierTree> bindingIdentifiers() {
     List<IdentifierTree> bindingIdentifiers = Lists.newArrayList();
 
     for (Optional<BindingElementTree> element : elements) {
-      if (element.isPresent()) {
-        bindingIdentifiers.addAll(element.get().bindingIdentifiers());
-      }
+      element.ifPresent(bindingElementTree -> bindingIdentifiers.addAll(bindingElementTree.bindingIdentifiers()));
     }
 
     return bindingIdentifiers;
@@ -110,10 +108,7 @@ private static class ElidedElementFilter implements Function<Optional<BindingEle
 
     @Override
     public BindingElementTree apply(Optional<BindingElementTree> e) {
-      if (e.isPresent()) {
-        return e.get();
-      }
-      return null;
+      return e.orElse(null);
     }
 
   }

javascript-frontend/src/main/java/org/sonar/javascript/tree/impl/expression/ArrayAssignmentPatternTreeImpl.java

@@ -86,10 +86,7 @@ private static class ElidedElementFilter implements Function<Optional<Tree>, Tre
 
     @Override
     public Tree apply(Optional<Tree> e) {
-      if (e.isPresent()) {
-        return e.get();
-      }
-      return null;
+      return e.orElse(null);
     }
 
   }

javascript-frontend/src/main/java/org/sonar/javascript/tree/impl/expression/BracketMemberExpressionTreeImpl.java

@@ -22,7 +22,6 @@
 import com.google.common.collect.Iterators;
 import java.util.Iterator;
 import org.sonar.javascript.tree.impl.JavaScriptTree;
-import org.sonar.javascript.tree.impl.lexical.InternalSyntaxToken;
 import org.sonar.javascript.tree.symbols.type.TypableTree;
 import org.sonar.plugins.javascript.api.symbols.Type;
 import org.sonar.plugins.javascript.api.symbols.TypeSet;

javascript-frontend/src/main/java/org/sonar/javascript/tree/impl/statement/BreakStatementTreeImpl.java

@@ -24,7 +24,6 @@
 import javax.annotation.Nullable;
 import org.sonar.javascript.tree.impl.JavaScriptTree;
 import org.sonar.plugins.javascript.api.tree.Tree;
-import org.sonar.plugins.javascript.api.tree.expression.IdentifierTree;
 import org.sonar.plugins.javascript.api.tree.lexical.SyntaxToken;
 import org.sonar.plugins.javascript.api.tree.statement.BreakStatementTree;
 import org.sonar.plugins.javascript.api.visitors.DoubleDispatchVisitor;

javascript-frontend/src/main/java/org/sonar/javascript/tree/impl/statement/ContinueStatementTreeImpl.java

@@ -24,7 +24,6 @@
 import javax.annotation.Nullable;
 import org.sonar.javascript.tree.impl.JavaScriptTree;
 import org.sonar.plugins.javascript.api.tree.Tree;
-import org.sonar.plugins.javascript.api.tree.expression.IdentifierTree;
 import org.sonar.plugins.javascript.api.tree.lexical.SyntaxToken;
 import org.sonar.plugins.javascript.api.tree.statement.ContinueStatementTree;
 import org.sonar.plugins.javascript.api.visitors.DoubleDispatchVisitor;

javascript-frontend/src/main/java/org/sonar/javascript/tree/impl/statement/LabelledStatementTreeImpl.java

@@ -24,7 +24,6 @@
 import org.sonar.javascript.tree.impl.JavaScriptTree;
 import org.sonar.javascript.tree.impl.lexical.InternalSyntaxToken;
 import org.sonar.plugins.javascript.api.tree.Tree;
-import org.sonar.plugins.javascript.api.tree.expression.IdentifierTree;
 import org.sonar.plugins.javascript.api.tree.lexical.SyntaxToken;
 import org.sonar.plugins.javascript.api.tree.statement.LabelledStatementTree;
 import org.sonar.plugins.javascript.api.tree.statement.StatementTree;

javascript-frontend/src/main/java/org/sonar/javascript/tree/symbols/type/TypeVisitor.java

@@ -203,7 +203,6 @@ private static void inferParameterType(CallExpressionTree tree) {
       int minSize = arguments.size() < parameters.size() ? arguments.size() : parameters.size();
 
       for (int i = 0; i < minSize; i++) {
-        Preconditions.checkState(arguments.get(i) instanceof ExpressionTree);
         Tree currentParameter = parameters.get(i);
         inferParameterType(currentParameter, arguments, i);
       }