From d12a24418e1dd94fafff5d53f178ace7557693dc Mon Sep 17 00:00:00 2001
From: Mark Punzalan <markpun@google.com>
Date: Wed, 26 May 2021 20:52:52 +0000
Subject: [PATCH] FIR IDE: Remove multiple nested params in
 RemoveUselessElvisFix and RemoveUselessCastFix.

---
 .../HighLevelQuickFixTestGenerated.java       | 30 +++++++++++++++++++
 .../idea/core/frontendIndependentPsiUtils.kt  | 16 ++++++----
 ...ssCastForLambdaInNecessaryNestedParens2.kt |  9 ++++++
 ...ForLambdaInNecessaryNestedParens2.kt.after |  9 ++++++
 ...emoveUselessCastForLambdaInNestedParens.kt |  5 ++++
 ...selessCastForLambdaInNestedParens.kt.after |  5 ++++
 .../removeUselessCastInNestedParens.kt        |  9 ++++++
 .../removeUselessCastInNestedParens.kt.after  |  9 ++++++
 ...ssElvisForLambdaInNecessaryNestedParens.kt |  8 +++++
 ...sForLambdaInNecessaryNestedParens.kt.after |  8 +++++
 .../uselessElvisForLambdaInNestedParens.kt    |  4 +++
 ...elessElvisForLambdaInNestedParens.kt.after |  4 +++
 .../expressions/uselessElvisInNestedParens.kt |  4 +++
 .../uselessElvisInNestedParens.kt.after       |  4 +++
 .../idea/quickfix/QuickFixTestGenerated.java  | 30 +++++++++++++++++++
 15 files changed, 148 insertions(+), 6 deletions(-)
 create mode 100644 idea/testData/quickfix/expressions/removeUselessCastForLambdaInNecessaryNestedParens2.kt
 create mode 100644 idea/testData/quickfix/expressions/removeUselessCastForLambdaInNecessaryNestedParens2.kt.after
 create mode 100644 idea/testData/quickfix/expressions/removeUselessCastForLambdaInNestedParens.kt
 create mode 100644 idea/testData/quickfix/expressions/removeUselessCastForLambdaInNestedParens.kt.after
 create mode 100644 idea/testData/quickfix/expressions/removeUselessCastInNestedParens.kt
 create mode 100644 idea/testData/quickfix/expressions/removeUselessCastInNestedParens.kt.after
 create mode 100644 idea/testData/quickfix/expressions/uselessElvisForLambdaInNecessaryNestedParens.kt
 create mode 100644 idea/testData/quickfix/expressions/uselessElvisForLambdaInNecessaryNestedParens.kt.after
 create mode 100644 idea/testData/quickfix/expressions/uselessElvisForLambdaInNestedParens.kt
 create mode 100644 idea/testData/quickfix/expressions/uselessElvisForLambdaInNestedParens.kt.after
 create mode 100644 idea/testData/quickfix/expressions/uselessElvisInNestedParens.kt
 create mode 100644 idea/testData/quickfix/expressions/uselessElvisInNestedParens.kt.after

diff --git a/idea/idea-fir/tests/org/jetbrains/kotlin/idea/quickfix/HighLevelQuickFixTestGenerated.java b/idea/idea-fir/tests/org/jetbrains/kotlin/idea/quickfix/HighLevelQuickFixTestGenerated.java
index 73d31fc7345..206dc2ce950 100644
--- a/idea/idea-fir/tests/org/jetbrains/kotlin/idea/quickfix/HighLevelQuickFixTestGenerated.java
+++ b/idea/idea-fir/tests/org/jetbrains/kotlin/idea/quickfix/HighLevelQuickFixTestGenerated.java
@@ -561,6 +561,16 @@ public class HighLevelQuickFixTestGenerated extends AbstractHighLevelQuickFixTes
             runTest("idea/testData/quickfix/expressions/removeUselessCast.kt");
         }
 
+        @TestMetadata("removeUselessCastForLambdaInNecessaryNestedParens2.kt")
+        public void testRemoveUselessCastForLambdaInNecessaryNestedParens2() throws Exception {
+            runTest("idea/testData/quickfix/expressions/removeUselessCastForLambdaInNecessaryNestedParens2.kt");
+        }
+
+        @TestMetadata("removeUselessCastForLambdaInNestedParens.kt")
+        public void testRemoveUselessCastForLambdaInNestedParens() throws Exception {
+            runTest("idea/testData/quickfix/expressions/removeUselessCastForLambdaInNestedParens.kt");
+        }
+
         @TestMetadata("removeUselessCastForLambdaInParens1.kt")
         public void testRemoveUselessCastForLambdaInParens1() throws Exception {
             runTest("idea/testData/quickfix/expressions/removeUselessCastForLambdaInParens1.kt");
@@ -591,6 +601,11 @@ public class HighLevelQuickFixTestGenerated extends AbstractHighLevelQuickFixTes
             runTest("idea/testData/quickfix/expressions/removeUselessCastForLambdaInParens6.kt");
         }
 
+        @TestMetadata("removeUselessCastInNestedParens.kt")
+        public void testRemoveUselessCastInNestedParens() throws Exception {
+            runTest("idea/testData/quickfix/expressions/removeUselessCastInNestedParens.kt");
+        }
+
         @TestMetadata("removeUselessCastInParens.kt")
         public void testRemoveUselessCastInParens() throws Exception {
             runTest("idea/testData/quickfix/expressions/removeUselessCastInParens.kt");
@@ -691,6 +706,21 @@ public class HighLevelQuickFixTestGenerated extends AbstractHighLevelQuickFixTes
             runTest("idea/testData/quickfix/expressions/uselessElvis.kt");
         }
 
+        @TestMetadata("uselessElvisForLambdaInNecessaryNestedParens.kt")
+        public void testUselessElvisForLambdaInNecessaryNestedParens() throws Exception {
+            runTest("idea/testData/quickfix/expressions/uselessElvisForLambdaInNecessaryNestedParens.kt");
+        }
+
+        @TestMetadata("uselessElvisForLambdaInNestedParens.kt")
+        public void testUselessElvisForLambdaInNestedParens() throws Exception {
+            runTest("idea/testData/quickfix/expressions/uselessElvisForLambdaInNestedParens.kt");
+        }
+
+        @TestMetadata("uselessElvisInNestedParens.kt")
+        public void testUselessElvisInNestedParens() throws Exception {
+            runTest("idea/testData/quickfix/expressions/uselessElvisInNestedParens.kt");
+        }
+
         @TestMetadata("uselessElvisRightIsNull.kt")
         public void testUselessElvisRightIsNull() throws Exception {
             runTest("idea/testData/quickfix/expressions/uselessElvisRightIsNull.kt");
diff --git a/idea/idea-frontend-independent/src/org/jetbrains/kotlin/idea/core/frontendIndependentPsiUtils.kt b/idea/idea-frontend-independent/src/org/jetbrains/kotlin/idea/core/frontendIndependentPsiUtils.kt
index 9f3f7d3d678..733f34a26bc 100644
--- a/idea/idea-frontend-independent/src/org/jetbrains/kotlin/idea/core/frontendIndependentPsiUtils.kt
+++ b/idea/idea-frontend-independent/src/org/jetbrains/kotlin/idea/core/frontendIndependentPsiUtils.kt
@@ -11,14 +11,21 @@ import org.jetbrains.kotlin.psi.KtParenthesizedExpression
 import org.jetbrains.kotlin.psi.KtPsiUtil
 
 inline fun <reified T : PsiElement> PsiElement.replaced(newElement: T): T {
+    if (this == newElement) return newElement
     val result = replace(newElement)
     return result as? T ?: (result as KtParenthesizedExpression).expression as T
 }
 
 fun KtExpression.dropEnclosingParenthesesIfPossible(): KtExpression {
-    val parent = parent as? KtParenthesizedExpression ?: return this
-    if (!KtPsiUtil.areParenthesesUseless(parent)) return this
-    return parent.replaced(this)
+    val innermostExpression = this
+    var current = innermostExpression
+
+    while (true) {
+        val parent = current.parent as? KtParenthesizedExpression ?: break
+        if (!KtPsiUtil.areParenthesesUseless(parent)) break
+        current = parent
+    }
+    return current.replaced(innermostExpression)
 }
 
 //todo make inline
@@ -26,6 +33,3 @@ fun KtExpression.dropEnclosingParenthesesIfPossible(): KtExpression {
 fun <T : PsiElement> T.copied(): T = copy() as T
 
 fun String.unquote(): String = KtPsiUtil.unquoteIdentifier(this)
-
-
-
diff --git a/idea/testData/quickfix/expressions/removeUselessCastForLambdaInNecessaryNestedParens2.kt b/idea/testData/quickfix/expressions/removeUselessCastForLambdaInNecessaryNestedParens2.kt
new file mode 100644
index 00000000000..e9cc904f8b8
--- /dev/null
+++ b/idea/testData/quickfix/expressions/removeUselessCastForLambdaInNecessaryNestedParens2.kt
@@ -0,0 +1,9 @@
+// "Remove useless cast" "true"
+fun foo() {}
+
+fun test() {
+    foo()
+    // comment
+    ((({ "" } as<caret> () -> String)))
+}
+/* IGNORE_FIR */
\ No newline at end of file
diff --git a/idea/testData/quickfix/expressions/removeUselessCastForLambdaInNecessaryNestedParens2.kt.after b/idea/testData/quickfix/expressions/removeUselessCastForLambdaInNecessaryNestedParens2.kt.after
new file mode 100644
index 00000000000..fb1192c5a1e
--- /dev/null
+++ b/idea/testData/quickfix/expressions/removeUselessCastForLambdaInNecessaryNestedParens2.kt.after
@@ -0,0 +1,9 @@
+// "Remove useless cast" "true"
+fun foo() {}
+
+fun test() {
+    foo()
+    // comment
+    ({ "" })
+}
+/* IGNORE_FIR */
\ No newline at end of file
diff --git a/idea/testData/quickfix/expressions/removeUselessCastForLambdaInNestedParens.kt b/idea/testData/quickfix/expressions/removeUselessCastForLambdaInNestedParens.kt
new file mode 100644
index 00000000000..0e16f44bb1d
--- /dev/null
+++ b/idea/testData/quickfix/expressions/removeUselessCastForLambdaInNestedParens.kt
@@ -0,0 +1,5 @@
+// "Remove useless cast" "true"
+fun test() {
+    ((({ "" } as<caret> () -> String)))
+}
+/* IGNORE_FIR */
\ No newline at end of file
diff --git a/idea/testData/quickfix/expressions/removeUselessCastForLambdaInNestedParens.kt.after b/idea/testData/quickfix/expressions/removeUselessCastForLambdaInNestedParens.kt.after
new file mode 100644
index 00000000000..9939faaaaec
--- /dev/null
+++ b/idea/testData/quickfix/expressions/removeUselessCastForLambdaInNestedParens.kt.after
@@ -0,0 +1,5 @@
+// "Remove useless cast" "true"
+fun test() {
+    { "" }
+}
+/* IGNORE_FIR */
\ No newline at end of file
diff --git a/idea/testData/quickfix/expressions/removeUselessCastInNestedParens.kt b/idea/testData/quickfix/expressions/removeUselessCastInNestedParens.kt
new file mode 100644
index 00000000000..460d34ffd5a
--- /dev/null
+++ b/idea/testData/quickfix/expressions/removeUselessCastInNestedParens.kt
@@ -0,0 +1,9 @@
+// "Remove useless cast" "true"
+fun test(x: Any): Int {
+    if (x is String) {
+        return (((x <caret>as String))).length
+    }
+    return -1
+}
+
+/* IGNORE_FIR */
\ No newline at end of file
diff --git a/idea/testData/quickfix/expressions/removeUselessCastInNestedParens.kt.after b/idea/testData/quickfix/expressions/removeUselessCastInNestedParens.kt.after
new file mode 100644
index 00000000000..3c49e654ca4
--- /dev/null
+++ b/idea/testData/quickfix/expressions/removeUselessCastInNestedParens.kt.after
@@ -0,0 +1,9 @@
+// "Remove useless cast" "true"
+fun test(x: Any): Int {
+    if (x is String) {
+        return x.length
+    }
+    return -1
+}
+
+/* IGNORE_FIR */
\ No newline at end of file
diff --git a/idea/testData/quickfix/expressions/uselessElvisForLambdaInNecessaryNestedParens.kt b/idea/testData/quickfix/expressions/uselessElvisForLambdaInNecessaryNestedParens.kt
new file mode 100644
index 00000000000..6c4e87b622c
--- /dev/null
+++ b/idea/testData/quickfix/expressions/uselessElvisForLambdaInNecessaryNestedParens.kt
@@ -0,0 +1,8 @@
+// "Remove useless elvis operator" "true"
+fun foo() {}
+
+fun test() {
+    foo()
+    // comment
+    ((({ "" } <caret>?: null)))
+}
diff --git a/idea/testData/quickfix/expressions/uselessElvisForLambdaInNecessaryNestedParens.kt.after b/idea/testData/quickfix/expressions/uselessElvisForLambdaInNecessaryNestedParens.kt.after
new file mode 100644
index 00000000000..d0280367b5e
--- /dev/null
+++ b/idea/testData/quickfix/expressions/uselessElvisForLambdaInNecessaryNestedParens.kt.after
@@ -0,0 +1,8 @@
+// "Remove useless elvis operator" "true"
+fun foo() {}
+
+fun test() {
+    foo()
+    // comment
+    ({ "" })
+}
diff --git a/idea/testData/quickfix/expressions/uselessElvisForLambdaInNestedParens.kt b/idea/testData/quickfix/expressions/uselessElvisForLambdaInNestedParens.kt
new file mode 100644
index 00000000000..244c000c84f
--- /dev/null
+++ b/idea/testData/quickfix/expressions/uselessElvisForLambdaInNestedParens.kt
@@ -0,0 +1,4 @@
+// "Remove useless elvis operator" "true"
+fun test() {
+    ((({ "" } <caret>?: null)))
+}
diff --git a/idea/testData/quickfix/expressions/uselessElvisForLambdaInNestedParens.kt.after b/idea/testData/quickfix/expressions/uselessElvisForLambdaInNestedParens.kt.after
new file mode 100644
index 00000000000..81171668112
--- /dev/null
+++ b/idea/testData/quickfix/expressions/uselessElvisForLambdaInNestedParens.kt.after
@@ -0,0 +1,4 @@
+// "Remove useless elvis operator" "true"
+fun test() {
+    { "" }
+}
diff --git a/idea/testData/quickfix/expressions/uselessElvisInNestedParens.kt b/idea/testData/quickfix/expressions/uselessElvisInNestedParens.kt
new file mode 100644
index 00000000000..c114f77568e
--- /dev/null
+++ b/idea/testData/quickfix/expressions/uselessElvisInNestedParens.kt
@@ -0,0 +1,4 @@
+// "Remove useless elvis operator" "true"
+fun foo(a: String) {
+    val b : String = (((a <caret>?: "s")))
+}
diff --git a/idea/testData/quickfix/expressions/uselessElvisInNestedParens.kt.after b/idea/testData/quickfix/expressions/uselessElvisInNestedParens.kt.after
new file mode 100644
index 00000000000..8ed7ed0f216
--- /dev/null
+++ b/idea/testData/quickfix/expressions/uselessElvisInNestedParens.kt.after
@@ -0,0 +1,4 @@
+// "Remove useless elvis operator" "true"
+fun foo(a: String) {
+    val b : String = a<caret>
+}
diff --git a/idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixTestGenerated.java b/idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixTestGenerated.java
index 90f0c8b6d32..2f517f339a0 100644
--- a/idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixTestGenerated.java
+++ b/idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixTestGenerated.java
@@ -7750,6 +7750,16 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
             runTest("idea/testData/quickfix/expressions/removeUselessCast.kt");
         }
 
+        @TestMetadata("removeUselessCastForLambdaInNecessaryNestedParens2.kt")
+        public void testRemoveUselessCastForLambdaInNecessaryNestedParens2() throws Exception {
+            runTest("idea/testData/quickfix/expressions/removeUselessCastForLambdaInNecessaryNestedParens2.kt");
+        }
+
+        @TestMetadata("removeUselessCastForLambdaInNestedParens.kt")
+        public void testRemoveUselessCastForLambdaInNestedParens() throws Exception {
+            runTest("idea/testData/quickfix/expressions/removeUselessCastForLambdaInNestedParens.kt");
+        }
+
         @TestMetadata("removeUselessCastForLambdaInParens1.kt")
         public void testRemoveUselessCastForLambdaInParens1() throws Exception {
             runTest("idea/testData/quickfix/expressions/removeUselessCastForLambdaInParens1.kt");
@@ -7780,6 +7790,11 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
             runTest("idea/testData/quickfix/expressions/removeUselessCastForLambdaInParens6.kt");
         }
 
+        @TestMetadata("removeUselessCastInNestedParens.kt")
+        public void testRemoveUselessCastInNestedParens() throws Exception {
+            runTest("idea/testData/quickfix/expressions/removeUselessCastInNestedParens.kt");
+        }
+
         @TestMetadata("removeUselessCastInParens.kt")
         public void testRemoveUselessCastInParens() throws Exception {
             runTest("idea/testData/quickfix/expressions/removeUselessCastInParens.kt");
@@ -7880,6 +7895,21 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
             runTest("idea/testData/quickfix/expressions/uselessElvis.kt");
         }
 
+        @TestMetadata("uselessElvisForLambdaInNecessaryNestedParens.kt")
+        public void testUselessElvisForLambdaInNecessaryNestedParens() throws Exception {
+            runTest("idea/testData/quickfix/expressions/uselessElvisForLambdaInNecessaryNestedParens.kt");
+        }
+
+        @TestMetadata("uselessElvisForLambdaInNestedParens.kt")
+        public void testUselessElvisForLambdaInNestedParens() throws Exception {
+            runTest("idea/testData/quickfix/expressions/uselessElvisForLambdaInNestedParens.kt");
+        }
+
+        @TestMetadata("uselessElvisInNestedParens.kt")
+        public void testUselessElvisInNestedParens() throws Exception {
+            runTest("idea/testData/quickfix/expressions/uselessElvisInNestedParens.kt");
+        }
+
         @TestMetadata("uselessElvisRightIsNull.kt")
         public void testUselessElvisRightIsNull() throws Exception {
             runTest("idea/testData/quickfix/expressions/uselessElvisRightIsNull.kt");