Convert to expression body is forbidden for if without else #KT-12951 Fixed

idea/testData/intentions/convertToExpressionBody/elvisIfElseUnit.kt

@@ -0,0 +1,9 @@
+// IS_APPLICABLE: true
+
+fun nullable() {}
+
+fun bar() {}
+
+fun foo(f: Boolean) {
+    <caret>nullable() ?: if (f) bar() else bar()
+}

idea/testData/intentions/convertToExpressionBody/elvisIfElseUnit.kt.after

@@ -0,0 +1,7 @@
+// IS_APPLICABLE: true
+
+fun nullable() {}
+
+fun bar() {}
+
+fun foo(f: Boolean) = nullable() ?: if (f) bar() else bar()

idea/testData/intentions/convertToExpressionBody/elvisIfUnit.kt

@@ -0,0 +1,9 @@
+// IS_APPLICABLE: false
+
+fun nullable() {}
+
+fun bar() {}
+
+fun foo(f: Boolean) {
+    <caret>nullable() ?: if (f) bar()
+}

idea/testData/intentions/convertToExpressionBody/ifElseUnit.kt

@@ -0,0 +1,7 @@
+// IS_APPLICABLE: true
+
+fun bar() {}
+
+fun foo(f: Boolean) {
+    <caret>if (f) bar() else bar()
+}

idea/testData/intentions/convertToExpressionBody/ifElseUnit.kt.after

@@ -0,0 +1,5 @@
+// IS_APPLICABLE: true
+
+fun bar() {}
+
+fun foo(f: Boolean) = if (f) bar() else bar()

idea/testData/intentions/convertToExpressionBody/ifUnit.kt

@@ -0,0 +1,7 @@
+// IS_APPLICABLE: false
+
+fun bar() {}
+
+fun foo(f: Boolean) {
+    <caret>if (f) bar()
+}

idea/testData/intentions/convertToExpressionBody/lambdaIfUnit.kt

@@ -0,0 +1,12 @@
+// IS_APPLICABLE: true
+
+fun <T> run(f: () -> T) = f()
+fun whenExpr(flag: Boolean) {
+    <caret>run {
+        println("run")
+        if (flag) {
+            println("flag")
+        }
+    }
+}
+fun println(s: String) {}

idea/testData/intentions/convertToExpressionBody/lambdaIfUnit.kt.after

@@ -0,0 +1,10 @@
+// IS_APPLICABLE: true
+
+fun <T> run(f: () -> T) = f()
+fun whenExpr(flag: Boolean) = run {
+    println("run")
+    if (flag) {
+        println("flag")
+    }
+}
+fun println(s: String) {}

idea/testData/intentions/convertToExpressionBody/whenIfUnitExhaustive.kt

@@ -0,0 +1,10 @@
+// IS_APPLICABLE: true
+enum class AccessMode { READ, WRITE, RW }
+fun whenExpr(mode: Boolean, access: AccessMode) {
+    <caret>when (access) {
+        AccessMode.READ -> if (mode) println("read") else println("noread")
+        AccessMode.WRITE -> if (mode) println("write") else println("nowrite")
+        AccessMode.RW -> if (mode) println("both") else println("no both")
+    }
+}
+fun println(s: String) {}

idea/testData/intentions/convertToExpressionBody/whenIfUnitExhaustive.kt.after

@@ -0,0 +1,8 @@
+// IS_APPLICABLE: true
+enum class AccessMode { READ, WRITE, RW }
+fun whenExpr(mode: Boolean, access: AccessMode) = when (access) {
+    AccessMode.READ -> if (mode) println("read") else println("noread")
+    AccessMode.WRITE -> if (mode) println("write") else println("nowrite")
+    AccessMode.RW -> if (mode) println("both") else println("no both")
+}
+fun println(s: String) {}

idea/testData/intentions/convertToExpressionBody/whenIfUnitNonExhaustive.kt

@@ -0,0 +1,10 @@
+// IS_APPLICABLE: false
+enum class AccessMode { READ, WRITE, RW }
+fun whenExpr(mode: Boolean, access: AccessMode) {
+    <caret>when (access) {
+        AccessMode.READ -> if (mode) println("read") else println("noread")
+        AccessMode.WRITE -> if (mode) println("write")
+        AccessMode.RW -> if (mode) println("both") else println("no both")
+    }
+}
+fun println(s: String) {}