Fix for incorrect variable name handle

diktat-rules/src/main/kotlin/org/cqfn/diktat/ruleset/rules/IdentifierNaming.kt

@@ -37,6 +37,7 @@ import org.cqfn.diktat.ruleset.utils.isPascalCase
 import org.cqfn.diktat.ruleset.utils.isTextLengthInRange
 import org.cqfn.diktat.ruleset.utils.isUpperSnakeCase
 import org.cqfn.diktat.ruleset.utils.removePrefix
+import org.cqfn.diktat.ruleset.utils.search.findAllVariablesWithUsages
 import org.cqfn.diktat.ruleset.utils.toLowerCamelCase
 import org.cqfn.diktat.ruleset.utils.toPascalCase
 import org.cqfn.diktat.ruleset.utils.toUpperSnakeCase
@@ -47,16 +48,21 @@ import com.pinterest.ktlint.core.ast.ElementType.CATCH
 import com.pinterest.ktlint.core.ast.ElementType.CATCH_KEYWORD
 import com.pinterest.ktlint.core.ast.ElementType.DESTRUCTURING_DECLARATION
 import com.pinterest.ktlint.core.ast.ElementType.DESTRUCTURING_DECLARATION_ENTRY
+import com.pinterest.ktlint.core.ast.ElementType.FILE
 import com.pinterest.ktlint.core.ast.ElementType.FUNCTION_TYPE
+import com.pinterest.ktlint.core.ast.ElementType.PROPERTY
 import com.pinterest.ktlint.core.ast.ElementType.REFERENCE_EXPRESSION
 import com.pinterest.ktlint.core.ast.ElementType.TYPE_PARAMETER
 import com.pinterest.ktlint.core.ast.ElementType.TYPE_REFERENCE
 import com.pinterest.ktlint.core.ast.ElementType.VALUE_PARAMETER_LIST
+import com.pinterest.ktlint.core.ast.parent
 import com.pinterest.ktlint.core.ast.prevCodeSibling
 import org.jetbrains.kotlin.builtins.PrimitiveType
 import org.jetbrains.kotlin.com.intellij.lang.ASTNode
 import org.jetbrains.kotlin.com.intellij.psi.impl.source.tree.LeafPsiElement
 import org.jetbrains.kotlin.com.intellij.psi.tree.TokenSet
+import org.jetbrains.kotlin.psi.KtProperty
+import org.jetbrains.kotlin.psi.psiUtil.isPrivate
 import org.jetbrains.kotlin.psi.psiUtil.parents
 
 /**
@@ -134,10 +140,12 @@ class IdentifierNaming(private val configRules: List<RulesConfig>) : Rule("ident
     /**
      * all checks for case and naming for vals/vars/constants
      */
-    @Suppress("SAY_NO_TO_VAR")
+    @Suppress("SAY_NO_TO_VAR", "TOO_LONG_FUNCTION", "ComplexMethod")
     private fun checkVariableName(node: ASTNode): List<ASTNode> {
         // special case for Destructuring declarations that can be treated as parameters in lambda:
         var namesOfVariables = extractVariableIdentifiers(node)
+        // only local private properties will be autofix in order not to break code if there are usages in other files
+        val isFix = isFixMode && if (node.elementType == PROPERTY) (node.psi as KtProperty).run { isLocal || isPrivate() } else true
         namesOfVariables
             .forEach { variableName ->
                 // variable should not contain only one letter in it's name. This is a bad example: b512
@@ -154,14 +162,19 @@ class IdentifierNaming(private val configRules: List<RulesConfig>) : Rule("ident
                 // it should be in UPPER_CASE, no need to raise this warning if it is one-letter variable
                 if (node.isConstant()) {
                     if (!variableName.text.isUpperSnakeCase() && variableName.text.length > 1) {
-                        CONSTANT_UPPERCASE.warnAndFix(configRules, emitWarn, isFixMode, variableName.text, variableName.startOffset, node) {
+                        CONSTANT_UPPERCASE.warnAndFix(configRules, emitWarn, isFix, variableName.text, variableName.startOffset, node) {
                             (variableName as LeafPsiElement).replaceWithText(variableName.text.toUpperSnakeCase())
                         }
                     }
                 } else if (variableName.text != "_" && !variableName.text.isLowerCamelCase()) {
                     // variable name should be in camel case. The only exception is a list of industry standard variables like i, j, k.
-                    VARIABLE_NAME_INCORRECT_FORMAT.warnAndFix(configRules, emitWarn, isFixMode, variableName.text, variableName.startOffset, node) {
+                    VARIABLE_NAME_INCORRECT_FORMAT.warnAndFix(configRules, emitWarn, isFix, variableName.text, variableName.startOffset, node) {
                         // FixMe: cover fixes with tests
+                        variableName
+                            .parent({it.elementType == FILE})
+                            ?.findAllVariablesWithUsages { it.name == variableName.text }
+                            ?.flatMap { it.value.toList() }
+                            ?.forEach { (it.node.firstChildNode as LeafPsiElement).replaceWithText(variableName.text.toLowerCamelCase())}
                         (variableName as LeafPsiElement).replaceWithText(variableName.text.toLowerCamelCase())
                     }
                 }

diktat-rules/src/test/resources/test/paragraph1/naming/identifiers/VariableNamingExpected.kt

@@ -10,3 +10,39 @@ private val loWerValue = ""
 private val lower = ""
 private val valNX256 = ""
 private val voiceIpPort = ""
+
+class A {
+    private val voiceIpPort = ""
+    public val valN_x2567 = ""
+
+    fun foo() {
+        val voiceIpPorts = ""
+        val upperSnakers = voiceIpPort
+        qww(voiceIpPorts)
+    }
+
+    fun goo() {
+        val qwe = lowerSnake
+        val pre = valNX256
+    }
+}
+
+class B {
+    companion object {
+        val QQ = 1
+        private val qwe = 11
+    }
+
+    fun foo() {
+        var qq = 20
+        while (qq < 20) {
+            qq = 10
+        }
+    }
+
+    class Ba {
+        fun goo() {
+            val qwe = QQ
+        }
+    }
+}

diktat-rules/src/test/resources/test/paragraph1/naming/identifiers/VariableNamingTest.kt

@@ -10,3 +10,39 @@ private val loWer_VAlue = ""
 private val lower = ""
 private val ValN_x256 = ""
 private val VoiceIP_port = ""
+
+class A {
+    private val VoiceIP_port = ""
+    public val valN_x2567 = ""
+
+    fun foo() {
+        val VoiceIP_ports = ""
+        val UPPER_SNAKERS = VoiceIP_port
+        qww(VoiceIP_ports)
+    }
+
+    fun goo() {
+        val qwe = lower_snake
+        val pre = ValN_x256
+    }
+}
+
+class B {
+    companion object {
+        val QQ = 1
+        private val QWE = 11
+    }
+
+    fun foo() {
+        var QQ = 20
+        while (QQ < 20) {
+            QQ = 10
+        }
+    }
+
+    class BA {
+        fun goo() {
+            val qwe = QQ
+        }
+    }
+}