Detect redundant semicolon before empty import list (#1072)

#KT-16577 Fixed

idea/src/org/jetbrains/kotlin/idea/inspections/RedundantSemicolonInspection.kt

@@ -25,6 +25,8 @@ import com.intellij.psi.PsiElementVisitor
 import com.intellij.psi.PsiWhiteSpace
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.KtEnumEntry
+import org.jetbrains.kotlin.psi.KtImportList
+import org.jetbrains.kotlin.psi.KtPackageDirective
 import org.jetbrains.kotlin.psi.psiUtil.nextLeaf
 
 class RedundantSemicolonInspection : AbstractKotlinInspection(), CleanupLocalInspectionTool {
@@ -46,7 +48,13 @@ class RedundantSemicolonInspection : AbstractKotlinInspection(), CleanupLocalIns
     private fun isRedundant(semicolon: PsiElement): Boolean {
         val nextLeaf = semicolon.nextLeaf { it !is PsiWhiteSpace && it !is PsiComment || it.isLineBreak()  }
         val isAtEndOfLine = nextLeaf == null || nextLeaf.isLineBreak()
-        if (!isAtEndOfLine) return false
+        if (!isAtEndOfLine) {
+            //when there is no imports parser generates empty import list with no spaces
+            if (semicolon.parent is KtPackageDirective && (nextLeaf as? KtImportList)?.imports?.isEmpty() ?: false) {
+                return true
+            }
+            return false
+        }
 
         if (semicolon.parent is KtEnumEntry) return false
 

idea/testData/inspections/redundantSemicolon/BeforeEmptyImports.kt

@@ -0,0 +1,3 @@
+package foo; // redundant
+
+class A

idea/testData/inspections/redundantSemicolon/inspectionData/expected.xml

@@ -61,4 +61,13 @@
         <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Redundant semicolon</problem_class>
         <description>Redundant semicolon</description>
     </problem>
+
+    <problem>
+        <file>BeforeEmptyImports.kt</file>
+        <line>1</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="BeforeEmptyImports.kt" />
+        <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Redundant semicolon</problem_class>
+        <description>Redundant semicolon</description>
+    </problem>
 </problems>