KT-14670 Support kotlinPackageName() macro in live templates (#1455)

* KT-14670 Support kotlinPackageName() macro in live templates

* Use context.psiElementAtStartOffset.containingFile #KT-14670

idea/idea-live-templates/src/org/jetbrains/kotlin/idea/liveTemplates/macro/KotlinPackageNameMacro.kt

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2010-2018 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.kotlin.idea.liveTemplates.macro
+
+import com.intellij.codeInsight.template.Expression
+import com.intellij.codeInsight.template.ExpressionContext
+import com.intellij.codeInsight.template.Result
+import com.intellij.codeInsight.template.TextResult
+import org.jetbrains.kotlin.psi.KtFile
+
+class KotlinPackageNameMacro : KotlinMacro() {
+    override fun getName() = "kotlinPackageName"
+    override fun getPresentableName() = "kotlinPackageName()"
+
+    override fun calculateResult(params: Array<Expression>, context: ExpressionContext): Result? {
+        val file = context.psiElementAtStartOffset?.containingFile as? KtFile ?: return null
+        val packageName = file.packageFqName.asString().takeIf { it.isNotEmpty() } ?: return null
+        return TextResult(packageName)
+    }
+}

idea/src/META-INF/plugin.xml

@@ -534,6 +534,7 @@
     <liveTemplateMacro implementation="org.jetbrains.kotlin.idea.liveTemplates.macro.SuggestVariableNameMacro"/>
     <liveTemplateMacro implementation="org.jetbrains.kotlin.idea.liveTemplates.macro.KotlinClassNameMacro"/>
     <liveTemplateMacro implementation="org.jetbrains.kotlin.idea.liveTemplates.macro.KotlinFunctionNameMacro"/>
+    <liveTemplateMacro implementation="org.jetbrains.kotlin.idea.liveTemplates.macro.KotlinPackageNameMacro"/>
     <liveTemplateOptionalProcessor implementation="org.jetbrains.kotlin.idea.liveTemplates.KotlinShortenFQNamesProcessor"/>
 
     <annotator language="kotlin" implementationClass="org.jetbrains.kotlin.idea.highlighter.KotlinPsiCheckerAndHighlightingUpdater"/>