From 26cdd0d5d52c6054bf381bc302d69f105b2a58cf Mon Sep 17 00:00:00 2001
From: Valentin Kipyatkov <valentin@jetbrains.com>
Date: Wed, 17 Aug 2016 18:06:34 +0300
Subject: [PATCH] KT-13482 "Loop can be replaced with stdlib operations"
 changes semantics

 #KT-13482 Fixed
---
 .../result/ForEachTransformation.kt                | 11 ++++++++---
 .../intentions/loopToCallChain/asSequenceOnly.kt   | 14 ++++++++++++++
 .../loopToCallChain/asSequenceOnly.kt.after2       | 13 +++++++++++++
 .../idea/intentions/IntentionTest2Generated.java   |  6 ++++++
 .../idea/intentions/IntentionTestGenerated.java    |  6 ++++++
 5 files changed, 47 insertions(+), 3 deletions(-)
 create mode 100644 idea/testData/intentions/loopToCallChain/asSequenceOnly.kt
 create mode 100644 idea/testData/intentions/loopToCallChain/asSequenceOnly.kt.after2

diff --git a/idea/src/org/jetbrains/kotlin/idea/intentions/loopToCallChain/result/ForEachTransformation.kt b/idea/src/org/jetbrains/kotlin/idea/intentions/loopToCallChain/result/ForEachTransformation.kt
index dd5dfcf8e99..2868420ead5 100644
--- a/idea/src/org/jetbrains/kotlin/idea/intentions/loopToCallChain/result/ForEachTransformation.kt
+++ b/idea/src/org/jetbrains/kotlin/idea/intentions/loopToCallChain/result/ForEachTransformation.kt
@@ -17,9 +17,9 @@
 package org.jetbrains.kotlin.idea.intentions.loopToCallChain.result
 
 import org.jetbrains.kotlin.idea.intentions.loopToCallChain.*
-import org.jetbrains.kotlin.psi.KtCallableDeclaration
-import org.jetbrains.kotlin.psi.KtExpression
-import org.jetbrains.kotlin.psi.KtForExpression
+import org.jetbrains.kotlin.psi.*
+import org.jetbrains.kotlin.psi.KtPsiUtil.isAssignment
+import org.jetbrains.kotlin.psi.psiUtil.anyDescendantOfType
 
 class ForEachTransformation(
         loop: KtForExpression,
@@ -53,6 +53,11 @@ class ForEachTransformation(
             if (state.previousTransformations.isEmpty()) return null // do not suggest conversion to just ".forEach{}" or ".forEachIndexed{}"
 
             val statement = state.statements.singleOrNull() ?: return null
+
+            // check if contains assignment to non-qualified variable - in this case only use of lazy sequence is correct
+            if (!state.lazySequence
+                && statement.anyDescendantOfType<KtBinaryExpression> { isAssignment(it) && it.left is KtNameReferenceExpression }) return null
+
             //TODO: should we disallow it for complicated statements like loops, if, when?
             val transformation = ForEachTransformation(state.outerLoop, state.inputVariable, state.indexVariable, statement)
             return TransformationMatch.Result(transformation)
diff --git a/idea/testData/intentions/loopToCallChain/asSequenceOnly.kt b/idea/testData/intentions/loopToCallChain/asSequenceOnly.kt
new file mode 100644
index 00000000000..e3dede069cf
--- /dev/null
+++ b/idea/testData/intentions/loopToCallChain/asSequenceOnly.kt
@@ -0,0 +1,14 @@
+// WITH_RUNTIME
+// IS_APPLICABLE: false
+// INTENTION_TEXT_2: "Replace with 'asSequence().filter{}.forEach{}'"
+fun getMaxLineWidth(lineCount: Int): Float {
+    var max_width = 0.0f
+    <caret>for (i in 0..lineCount - 1) {
+        if (getLineWidth(i) > max_width) {
+            max_width = getLineWidth(i)
+        }
+    }
+    return max_width
+}
+
+fun  getLineWidth(i: Int): Float = TODO()
diff --git a/idea/testData/intentions/loopToCallChain/asSequenceOnly.kt.after2 b/idea/testData/intentions/loopToCallChain/asSequenceOnly.kt.after2
new file mode 100644
index 00000000000..297c28eb432
--- /dev/null
+++ b/idea/testData/intentions/loopToCallChain/asSequenceOnly.kt.after2
@@ -0,0 +1,13 @@
+// WITH_RUNTIME
+// IS_APPLICABLE: false
+// INTENTION_TEXT_2: "Replace with 'asSequence().filter{}.forEach{}'"
+fun getMaxLineWidth(lineCount: Int): Float {
+    var max_width = 0.0f
+    <caret>(0..lineCount - 1)
+            .asSequence()
+            .filter { getLineWidth(it) > max_width }
+            .forEach { max_width = getLineWidth(it) }
+    return max_width
+}
+
+fun  getLineWidth(i: Int): Float = TODO()
diff --git a/idea/tests/org/jetbrains/kotlin/idea/intentions/IntentionTest2Generated.java b/idea/tests/org/jetbrains/kotlin/idea/intentions/IntentionTest2Generated.java
index 26f0364e466..ecb0d61cf9a 100644
--- a/idea/tests/org/jetbrains/kotlin/idea/intentions/IntentionTest2Generated.java
+++ b/idea/tests/org/jetbrains/kotlin/idea/intentions/IntentionTest2Generated.java
@@ -131,6 +131,12 @@ public class IntentionTest2Generated extends AbstractIntentionTest2 {
         doTest(fileName);
     }
 
+    @TestMetadata("asSequenceOnly.kt")
+    public void testAsSequenceOnly() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("idea/testData/intentions/loopToCallChain/asSequenceOnly.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("assignFilter.kt")
     public void testAssignFilter() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("idea/testData/intentions/loopToCallChain/assignFilter.kt");
diff --git a/idea/tests/org/jetbrains/kotlin/idea/intentions/IntentionTestGenerated.java b/idea/tests/org/jetbrains/kotlin/idea/intentions/IntentionTestGenerated.java
index 5c86385ccb0..96bb2b54fa7 100644
--- a/idea/tests/org/jetbrains/kotlin/idea/intentions/IntentionTestGenerated.java
+++ b/idea/tests/org/jetbrains/kotlin/idea/intentions/IntentionTestGenerated.java
@@ -7291,6 +7291,12 @@ public class IntentionTestGenerated extends AbstractIntentionTest {
             doTest(fileName);
         }
 
+        @TestMetadata("asSequenceOnly.kt")
+        public void testAsSequenceOnly() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/intentions/loopToCallChain/asSequenceOnly.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("assignFilter.kt")
         public void testAssignFilter() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/testData/intentions/loopToCallChain/assignFilter.kt");