Add Boolean? == const to elvis conversion and vice versa #KT-15368 Fixed

Convert elvis to equality check implemented as inspection due
code style guide

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

@@ -0,0 +1,51 @@
+<problems>
+    <problem>
+        <file>test.kt</file>
+        <line>4</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="test.kt"/>
+        <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Equality check can be used instead of elvis</problem_class>
+        <description>Equality check can be used instead of elvis</description>
+    </problem>
+    <problem>
+        <file>test.kt</file>
+        <line>7</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="test.kt"/>
+        <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Equality check can be used instead of elvis</problem_class>
+        <description>Equality check can be used instead of elvis</description>
+    </problem>
+    <problem>
+        <file>test.kt</file>
+        <line>10</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="test.kt"/>
+        <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Equality check can be used instead of elvis</problem_class>
+        <description>Equality check can be used instead of elvis</description>
+    </problem>
+    <problem>
+        <file>test.kt</file>
+        <line>10</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="test.kt"/>
+        <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Equality check can be used instead of elvis</problem_class>
+        <description>Equality check can be used instead of elvis</description>
+    </problem>
+    <problem>
+        <file>test.kt</file>
+        <line>13</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="test.kt"/>
+        <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Equality check can be used instead of elvis</problem_class>
+        <description>Equality check can be used instead of elvis</description>
+    </problem>
+    <problem>
+        <file>test.kt</file>
+        <line>14</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="test.kt"/>
+        <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Equality check can be used instead of elvis</problem_class>
+        <description>Equality check can be used instead of elvis</description>
+    </problem>
+
+</problems>

idea/testData/inspections/nullableBooleanElvis/inspectionData/inspections.test

@@ -0,0 +1 @@
+// INSPECTION_CLASS: org.jetbrains.kotlin.idea.inspections.NullableBooleanElvisInspection

idea/testData/inspections/nullableBooleanElvis/test.kt

@@ -0,0 +1,15 @@
+fun foo() {
+    var a: Boolean? = null
+    var b: Boolean? = null
+    if (a ?: false) {
+
+    }
+    if (!(a ?: false)) {
+
+    }
+    if (a ?: false || !(b ?: true)) {
+
+    }
+    val x = a ?: false
+    val y = !(b ?: true)
+}

idea/testData/inspectionsLocal/nullableBooleanElvis/.inspection

@@ -0,0 +1 @@
+org.jetbrains.kotlin.idea.inspections.NullableBooleanElvisInspection

idea/testData/inspectionsLocal/nullableBooleanElvis/inIf.kt

@@ -0,0 +1,6 @@
+fun foo() {
+    var a: Boolean? = null
+    if (a <caret>?: false) {
+
+    }
+}

idea/testData/inspectionsLocal/nullableBooleanElvis/inIf.kt.after

@@ -0,0 +1,6 @@
+fun foo() {
+    var a: Boolean? = null
+    if (a == true) {
+
+    }
+}

idea/testData/inspectionsLocal/nullableBooleanElvis/inIf2.kt

@@ -0,0 +1,6 @@
+fun foo() {
+    var a: Boolean? = null
+    if (!(a <caret>?: false)) {
+
+    }
+}

idea/testData/inspectionsLocal/nullableBooleanElvis/inIf2.kt.after

@@ -0,0 +1,6 @@
+fun foo() {
+    var a: Boolean? = null
+    if (a != true) {
+
+    }
+}

idea/testData/inspectionsLocal/nullableBooleanElvis/inIf3.kt

@@ -0,0 +1,7 @@
+fun foo() {
+    var a: Boolean? = null
+    var b: Boolean? = null
+    if (a ?: false || !(b<caret> ?: true)) {
+
+    }
+}

idea/testData/inspectionsLocal/nullableBooleanElvis/inIf3.kt.after

@@ -0,0 +1,7 @@
+fun foo() {
+    var a: Boolean? = null
+    var b: Boolean? = null
+    if (a ?: false || b == false) {
+
+    }
+}

idea/testData/inspectionsLocal/nullableBooleanElvis/notInIf.kt

@@ -0,0 +1,4 @@
+fun foo() {
+    var a: Boolean? = null
+    val x = a<caret> ?: false
+}

idea/testData/inspectionsLocal/nullableBooleanElvis/notInIf.kt.after

@@ -0,0 +1,4 @@
+fun foo() {
+    var a: Boolean? = null
+    val x = a == true
+}

idea/testData/inspectionsLocal/nullableBooleanElvis/notInIfWithTrue.kt

@@ -0,0 +1,4 @@
+fun foo() {
+    var b: Boolean? = null
+    val x = !(b <caret>?: true)
+}

idea/testData/inspectionsLocal/nullableBooleanElvis/notInIfWithTrue.kt.after

@@ -0,0 +1,4 @@
+fun foo() {
+    var b: Boolean? = null
+    val x = b == false
+}

idea/testData/intentions/nullableBooleanEqualityCheckToElvis/.intention

@@ -0,0 +1 @@
+org.jetbrains.kotlin.idea.intentions.NullableBooleanEqualityCheckToElvisIntention

idea/testData/intentions/nullableBooleanEqualityCheckToElvis/eqFalse.kt

@@ -0,0 +1,6 @@
+fun foo() {
+    val a: Boolean? = null
+    if (a<caret> == false) {
+
+    }
+}

idea/testData/intentions/nullableBooleanEqualityCheckToElvis/eqFalse.kt.after

@@ -0,0 +1,6 @@
+fun foo() {
+    val a: Boolean? = null
+    if (!(a ?: true)) {
+
+    }
+}

idea/testData/intentions/nullableBooleanEqualityCheckToElvis/eqTrue.kt

@@ -0,0 +1,6 @@
+fun foo() {
+    val a: Boolean? = null
+    if (a<caret> == true) {
+
+    }
+}

idea/testData/intentions/nullableBooleanEqualityCheckToElvis/eqTrue.kt.after

@@ -0,0 +1,6 @@
+fun foo() {
+    val a: Boolean? = null
+    if (a ?: false) {
+
+    }
+}

idea/testData/intentions/nullableBooleanEqualityCheckToElvis/flexible.kt

@@ -0,0 +1,4 @@
+fun foo() {
+    val a = java.lang.Boolean.valueOf("true")
+    if (a<caret> == true) {}
+}

idea/testData/intentions/nullableBooleanEqualityCheckToElvis/flexible.kt.after

@@ -0,0 +1,4 @@
+fun foo() {
+    val a = java.lang.Boolean.valueOf("true")
+    if (a ?: false) {}
+}

idea/testData/intentions/nullableBooleanEqualityCheckToElvis/notEqFalse.kt

@@ -0,0 +1,6 @@
+fun foo() {
+    val a: Boolean? = null
+    if (a<caret> != false) {
+
+    }
+}

idea/testData/intentions/nullableBooleanEqualityCheckToElvis/notEqFalse.kt.after

@@ -0,0 +1,6 @@
+fun foo() {
+    val a: Boolean? = null
+    if (a ?: true) {
+
+    }
+}

idea/testData/intentions/nullableBooleanEqualityCheckToElvis/notEqTrue.kt

@@ -0,0 +1,6 @@
+fun foo() {
+    val a: Boolean? = null
+    if (a<caret> != true) {
+
+    }
+}

idea/testData/intentions/nullableBooleanEqualityCheckToElvis/notEqTrue.kt.after

@@ -0,0 +1,6 @@
+fun foo() {
+    val a: Boolean? = null
+    if (!(a ?: false)) {
+
+    }
+}