Remove redundant let in "Safe access to if-then" #KT-13515 Fixed

idea/testData/intentions/branched/safeAccessToIfThen/let.kt

@@ -0,0 +1,5 @@
+// WITH_RUNTIME
+
+fun foo(value: Int?): Int? {
+    return value<caret>?.let { it + 1 }
+}

idea/testData/intentions/branched/safeAccessToIfThen/let.kt.after

@@ -0,0 +1,5 @@
+// WITH_RUNTIME
+
+fun foo(value: Int?): Int? {
+    return if (value != null) value + 1 else null
+}

idea/testData/intentions/branched/safeAccessToIfThen/let2.kt

@@ -0,0 +1,7 @@
+// WITH_RUNTIME
+
+fun foo(value: Int?): Int? {
+    return value<caret>?.let { baz(it) }
+}
+
+fun baz(i: Int) = i + i

idea/testData/intentions/branched/safeAccessToIfThen/let2.kt.after

@@ -0,0 +1,7 @@
+// WITH_RUNTIME
+
+fun foo(value: Int?): Int? {
+    return if (value != null) baz(value) else null
+}
+
+fun baz(i: Int) = i + i

idea/testData/intentions/branched/safeAccessToIfThen/let3.kt

@@ -0,0 +1,5 @@
+// WITH_RUNTIME
+
+fun foo(a: Int, b: Int?): Int? {
+    return b<caret>?.let { a + b }
+}

idea/testData/intentions/branched/safeAccessToIfThen/let3.kt.after

@@ -0,0 +1,5 @@
+// WITH_RUNTIME
+
+fun foo(a: Int, b: Int?): Int? {
+    return if (b != null) b.let { a + b } else null
+}

idea/testData/intentions/branched/safeAccessToIfThen/letNotRedundant.kt

@@ -0,0 +1,8 @@
+// WITH_RUNTIME
+
+fun foo(value: Int?): Int? {
+    return value<caret>?.let {
+        println()
+        it + 1
+    }
+}

idea/testData/intentions/branched/safeAccessToIfThen/letNotRedundant.kt.after

@@ -0,0 +1,8 @@
+// WITH_RUNTIME
+
+fun foo(value: Int?): Int? {
+    return if (value != null) value.let {
+        println()
+        it + 1
+    } else null
+}

idea/testData/intentions/branched/safeAccessToIfThen/letTopLevelVar.kt

@@ -0,0 +1,6 @@
+// WITH_RUNTIME
+
+var a: String? = "A"
+fun main(args: Array<String>) {
+    a<caret>?.let { it.length + 1 }
+}

idea/testData/intentions/branched/safeAccessToIfThen/letTopLevelVar.kt.after

@@ -0,0 +1,7 @@
+// WITH_RUNTIME
+
+var a: String? = "A"
+fun main(args: Array<String>) {
+    val a1 = a
+    if (a1 != null) a1.length + 1
+}