[groovy] make semicolon necessary by default (IDEA-192360)

- highlight only known unnecessary semicolon cases;
- move messages to bundle;
- extract the fix to separate class.

plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/codeInspection/GroovyInspectionBundle.properties

@@ -123,4 +123,6 @@ unnecessary.modifier.description=Modifier ''{0}'' is not necessary
 unnecessary.modifier.remove=Remove unnecessary ''{0}''
 unnecessary.def.explicitly.typed.only=Only report in explicitly typed declarations
 unnecessary.alias.fix=Remove unnecessary alias
-unnecessary.alias.description=Alias is unnecessary
+unnecessary.alias.description=Alias is unnecessary
+unnecessary.semicolon.description=Semicolon is unnecessary
+unnecessary.semicolon.fix=Remove semicolon

plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/codeInspection/fixes/RemoveElementWithoutFormatterFix.kt

@@ -0,0 +1,19 @@
+// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package org.jetbrains.plugins.groovy.codeInspection.fixes
+
+import com.intellij.codeInspection.LocalQuickFix
+import com.intellij.codeInspection.ProblemDescriptor
+import com.intellij.openapi.project.Project
+import com.intellij.psi.codeStyle.CodeStyleManager
+
+class RemoveElementWithoutFormatterFix(private val familyName: String) : LocalQuickFix {
+
+  override fun getFamilyName(): String = familyName
+
+  override fun applyFix(project: Project, descriptor: ProblemDescriptor) {
+    val element = descriptor.psiElement ?: return
+    CodeStyleManager.getInstance(project).performActionWithFormatterDisabled {
+      element.delete()
+    }
+  }
+}

plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/codeInspection/style/GrUnnecessarySemicolonInspection.java

@@ -1,84 +0,0 @@
-/*
- * Copyright 2000-2016 JetBrains s.r.o.
- *
- * 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 org.jetbrains.plugins.groovy.codeInspection.style;
-
-import com.intellij.codeInspection.*;
-import com.intellij.openapi.project.Project;
-import com.intellij.psi.PsiElement;
-import com.intellij.psi.PsiElementVisitor;
-import com.intellij.psi.codeStyle.CodeStyleManager;
-import com.intellij.psi.tree.TokenSet;
-import org.jetbrains.annotations.Nls;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.plugins.groovy.codeInspection.GroovySuppressableInspectionTool;
-import org.jetbrains.plugins.groovy.lang.psi.api.statements.GrStatement;
-import org.jetbrains.plugins.groovy.lang.psi.api.statements.blocks.GrClosableBlock;
-import org.jetbrains.plugins.groovy.lang.psi.api.statements.clauses.GrTraditionalForClause;
-import org.jetbrains.plugins.groovy.lang.psi.util.PsiUtil;
-
-import static com.intellij.psi.tree.TokenSet.andNot;
-import static com.intellij.psi.tree.TokenSet.orSet;
-import static org.jetbrains.plugins.groovy.lang.lexer.GroovyTokenTypes.mNLS;
-import static org.jetbrains.plugins.groovy.lang.lexer.GroovyTokenTypes.mSEMI;
-import static org.jetbrains.plugins.groovy.lang.lexer.TokenSets.WHITE_SPACES_OR_COMMENTS;
-
-public class GrUnnecessarySemicolonInspection extends GroovySuppressableInspectionTool implements CleanupLocalInspectionTool {
-
-  private static final TokenSet NLS_SET = TokenSet.create(mNLS);
-  private static final TokenSet FORWARD_SET = andNot(orSet(WHITE_SPACES_OR_COMMENTS, TokenSet.create(mSEMI)), NLS_SET);
-  private static final TokenSet BACKWARD_SET = andNot(WHITE_SPACES_OR_COMMENTS, NLS_SET);
-
-  private static final LocalQuickFix FIX = new LocalQuickFix() {
-
-    @Nls
-    @NotNull
-    @Override
-    public String getFamilyName() {
-      return "Remove semicolon";
-    }
-
-    @Override
-    public void applyFix(@NotNull Project project, @NotNull ProblemDescriptor descriptor) {
-      PsiElement element = descriptor.getPsiElement();
-      if (element != null && element.getNode().getElementType() == mSEMI) {
-        CodeStyleManager.getInstance(project).performActionWithFormatterDisabled((Runnable)element::delete);
-      }
-    }
-  };
-
-  @NotNull
-  @Override
-  public PsiElementVisitor buildVisitor(@NotNull ProblemsHolder holder, boolean isOnTheFly) {
-    return new PsiElementVisitor() {
-      @Override
-      public void visitElement(PsiElement element) {
-        if (element.getNode().getElementType() != mSEMI) return;
-        if (isSemicolonNecessary(element)) return;
-        holder.registerProblem(element, "Semicolon is unnecessary", ProblemHighlightType.LIKE_UNUSED_SYMBOL, FIX);
-      }
-    };
-  }
-
-  private static boolean isSemicolonNecessary(@NotNull PsiElement semicolon) {
-    if (semicolon.getParent() instanceof GrTraditionalForClause) return true;
-
-    PsiElement prevSibling = PsiUtil.skipSet(semicolon, false, BACKWARD_SET);
-    PsiElement nextSibling = PsiUtil.skipSet(semicolon, true, FORWARD_SET);
-    return prevSibling instanceof GrStatement && (
-      nextSibling instanceof GrStatement || nextSibling != null && nextSibling.getNextSibling() instanceof GrClosableBlock
-    );
-  }
-}

plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/codeInspection/style/GrUnnecessarySemicolonInspection.kt

@@ -0,0 +1,77 @@
+// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package org.jetbrains.plugins.groovy.codeInspection.style
+
+import com.intellij.codeInspection.CleanupLocalInspectionTool
+import com.intellij.codeInspection.ProblemHighlightType
+import com.intellij.codeInspection.ProblemsHolder
+import com.intellij.psi.PsiElement
+import com.intellij.psi.PsiElementVisitor
+import org.jetbrains.plugins.groovy.codeInspection.GroovyInspectionBundle.message
+import org.jetbrains.plugins.groovy.codeInspection.GroovySuppressableInspectionTool
+import org.jetbrains.plugins.groovy.codeInspection.fixes.RemoveElementWithoutFormatterFix
+import org.jetbrains.plugins.groovy.lang.lexer.TokenSets.WHITE_SPACES_OR_COMMENTS
+import org.jetbrains.plugins.groovy.lang.psi.GroovyElementTypes.*
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.GrStatement
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.blocks.GrClosableBlock
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.clauses.GrTraditionalForClause
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.params.GrParameterList
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.typedef.members.GrEnumConstantList
+import org.jetbrains.plugins.groovy.lang.psi.api.toplevel.imports.GrImportStatement
+import org.jetbrains.plugins.groovy.lang.psi.api.toplevel.packaging.GrPackageDefinition
+import org.jetbrains.plugins.groovy.lang.psi.util.PsiUtil.skipSet
+import org.jetbrains.plugins.groovy.util.TokenSet
+import org.jetbrains.plugins.groovy.util.minus
+import org.jetbrains.plugins.groovy.util.plus
+
+class GrUnnecessarySemicolonInspection : GroovySuppressableInspectionTool(), CleanupLocalInspectionTool {
+
+  override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean): PsiElementVisitor = object : PsiElementVisitor() {
+    override fun visitElement(element: PsiElement) {
+      if (element.node.elementType !== T_SEMI || isSemicolonNecessary(element)) return
+      holder.registerProblem(
+        element,
+        message("unnecessary.semicolon.description"),
+        ProblemHighlightType.LIKE_UNUSED_SYMBOL,
+        fix
+      )
+    }
+  }
+
+  companion object {
+
+    private val fix = RemoveElementWithoutFormatterFix(message("unnecessary.semicolon.fix"))
+    private val nlSet = TokenSet(NL)
+    private val forwardSet = WHITE_SPACES_OR_COMMENTS + TokenSet(T_SEMI) - nlSet
+    private val backwardSet = WHITE_SPACES_OR_COMMENTS - nlSet
+    private val separators = TokenSet(NL, T_SEMI)
+    private val previousSet = TokenSet(T_LBRACE, T_ARR)
+
+    private fun isSemicolonNecessary(semicolon: PsiElement): Boolean {
+      if (semicolon.parent is GrTraditionalForClause) return true
+
+      val prevSibling = skipSet(semicolon, false, backwardSet) ?: return false
+      val nextSibling = skipSet(semicolon, true, forwardSet) ?: return false
+
+      val prevType = prevSibling.node.elementType
+
+      return when {
+        prevType in separators -> {
+          prevSibling.prevSibling is GrEnumConstantList
+        }
+        prevType in previousSet -> {
+          false
+        }
+        prevSibling is GrStatement -> {
+          nextSibling is GrStatement || nextSibling.nextSibling is GrClosableBlock
+        }
+        prevSibling is GrPackageDefinition || prevSibling is GrImportStatement -> {
+          nextSibling.node.elementType !in separators
+        }
+        prevSibling is GrParameterList && prevSibling.parent is GrClosableBlock -> {
+          false // beginning of a closure
+        }
+        else -> true
+      }
+    }
+  }
+}

plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/util/tokenSet.kt

@@ -0,0 +1,14 @@
+// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package org.jetbrains.plugins.groovy.util
+
+import com.intellij.psi.tree.IElementType
+import com.intellij.psi.tree.TokenSet
+import com.intellij.psi.tree.TokenSet.andNot
+import com.intellij.psi.tree.TokenSet.orSet
+
+operator fun TokenSet.plus(another: TokenSet): TokenSet = orSet(this, another)
+
+operator fun TokenSet.minus(another: TokenSet): TokenSet = andNot(this, another)
+
+@Suppress("FunctionName")
+fun TokenSet(vararg tokens: IElementType): TokenSet = TokenSet.create(*tokens)

plugins/groovy/test/org/jetbrains/plugins/groovy/codeInspection/style/GrUnnecessarySemicolonInspectionTest.groovy

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2016 JetBrains s.r.o.
- *
- * 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.
- */
+// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package org.jetbrains.plugins.groovy.codeInspection.style
 
 import com.intellij.testFramework.LightProjectDescriptor
@@ -91,7 +77,7 @@ print(a); /*asd*/
     doTest 'foo {; ;1;;/*asd*/;54; ;<caret>;; }', 'foo { 1;/*asd*/54  }'
   }
 
-  void 'test within closure with arrow' () {
+  void 'test within closure with arrow'() {
     doTest 'foo { -> ; ;1;;/*asd*/;54; ;<caret>;; }', 'foo { ->  1;/*asd*/54  }'
   }
 
@@ -111,6 +97,47 @@ class A {
 '''
   }
 
+  void 'test after package definition'() {
+    doTest 'package com.foo<caret>; import java.lang.String'
+    doTest '''\
+package com.foo<caret>; 
+import java.lang.String
+''', '''\
+package com.foo 
+import java.lang.String
+'''
+  }
+
+  void 'test after import definition'() {
+    doTest 'import java.lang.String<caret>; import java.lang.String'
+    doTest '''\
+import java.lang.String<caret>;
+import java.lang.String;
+''', '''\
+import java.lang.String
+import java.lang.String
+'''
+  }
+
+  void 'test after enum constants'() {
+    doTest '''\
+enum E {
+  foo, bar, <caret>;  
+  E() {}
+}
+'''
+    doTest '''\
+enum E {
+  foo, bar, 
+  
+  <caret>;  
+  
+  
+  E() {}
+}
+'''
+  }
+
   private doTest(String before, String after) {
     fixture.with {
       enableInspections GrUnnecessarySemicolonInspection
@@ -124,7 +151,7 @@ class A {
     fixture.with {
       enableInspections GrUnnecessarySemicolonInspection
       configureByText '_.groovy', text
-      checkHighlighting()
+      assertNull(getAvailableIntention("Fix all 'Unnecessary semicolon'"))
     }
   }