Repository: cqfn/diKTat (kotlin)

Issue:
Bug in autofix in string templates
## Describe the bug
```kotlin
        val dockerFileAsText =
                """
                    FROM $baseImage
                    COPY resources $resourcesPath
                    RUN /bin/bash
                """.trimIndent()  // RUN command shouldn't matter because it will be replaced on container creation
```
after fixinig space is removed after `FROM~ and `resources`

## Environment information
* diktat version: 0.4.0

Pull request description:
### What's done:
  * Fixed bug
  * Added to smoke test


This pull request closes #766

Patch:
diff --git a/diktat-rules/src/main/kotlin/org/cqfn/diktat/ruleset/rules/chapter3/files/IndentationRule.kt b/diktat-rules/src/main/kotlin/org/cqfn/diktat/ruleset/rules/chapter3/files/IndentationRule.kt
index bad5240b9d..a2c6220c0a 100644
--- a/diktat-rules/src/main/kotlin/org/cqfn/diktat/ruleset/rules/chapter3/files/IndentationRule.kt
+++ b/diktat-rules/src/main/kotlin/org/cqfn/diktat/ruleset/rules/chapter3/files/IndentationRule.kt
@@ -41,6 +41,7 @@ import com.pinterest.ktlint.core.ast.ElementType.RBRACE
 import com.pinterest.ktlint.core.ast.ElementType.RBRACKET
 import com.pinterest.ktlint.core.ast.ElementType.RPAR
 import com.pinterest.ktlint.core.ast.ElementType.SAFE_ACCESS_EXPRESSION
+import com.pinterest.ktlint.core.ast.ElementType.SHORT_STRING_TEMPLATE_ENTRY
 import com.pinterest.ktlint.core.ast.ElementType.STRING_TEMPLATE
 import com.pinterest.ktlint.core.ast.ElementType.THEN
 import com.pinterest.ktlint.core.ast.ElementType.WHITE_SPACE
@@ -59,6 +60,7 @@ import org.jetbrains.kotlin.psi.psiUtil.parents
 import org.jetbrains.kotlin.psi.psiUtil.parentsWithSelf
 import org.jetbrains.kotlin.psi.psiUtil.startOffset
 import org.jetbrains.kotlin.utils.addToStdlib.firstNotNullResult
+import java.lang.StringBuilder
 import kotlin.math.abs
 
 /**
@@ -196,7 +198,7 @@ class IndentationRule(configRules: List<RulesConfig>) : DiktatRule(
         if (checkResult?.isCorrect != true && expectedIndent != indentError.actual) {
             WRONG_INDENTATION.warnAndFix(configRules, emitWarn, isFixMode, "expected $expectedIndent but was ${indentError.actual}",
                 whiteSpace.startOffset + whiteSpace.text.lastIndexOf('\n') + 1, whiteSpace.node) {
-                checkStringLiteral(whiteSpace, expectedIndent)
+                checkStringLiteral(whiteSpace, expectedIndent, indentError.actual)
                 whiteSpace.node.indentBy(expectedIndent)
             }
         }
@@ -205,7 +207,11 @@ class IndentationRule(configRules: List<RulesConfig>) : DiktatRule(
     /**
      * Checks if it is triple-quoted string template with trimIndent() or trimMargin() function.
      */
-    private fun checkStringLiteral(whiteSpace: PsiWhiteSpace, expectedIndent: Int) {
+    private fun checkStringLiteral(
+        whiteSpace: PsiWhiteSpace,
+        expectedIndent: Int,
+        actualIndent: Int
+    ) {
         val nextNode = whiteSpace.node.treeNext
         if (nextNode != null &&
                 nextNode.elementType == DOT_QUALIFIED_EXPRESSION &&
@@ -215,19 +221,23 @@ class IndentationRule(configRules: List<RulesConfig>) : DiktatRule(
                     it == "trimIndent()" ||
                             it == "trimMargin()"
                 } == true) {
-            fixStringLiteral(whiteSpace, expectedIndent)
+            fixStringLiteral(whiteSpace, expectedIndent, actualIndent)
         }
     }
 
     /**
      * If it is triple-quoted string template we need to indent all its parts
      */
-    private fun fixStringLiteral(whiteSpace: PsiWhiteSpace, expectedIndent: Int) {
+    private fun fixStringLiteral(
+        whiteSpace: PsiWhiteSpace,
+        expectedIndent: Int,
+        actualIndent: Int
+    ) {
         val textIndent = " ".repeat(expectedIndent + INDENT_SIZE)
         val templateEntries = whiteSpace.node.treeNext.firstChildNode.getAllChildrenWithType(LITERAL_STRING_TEMPLATE_ENTRY)
-        templateEntries.forEach {
-            if (!it.text.contains("\n") && it.text.isNotBlank()) {
-                (it.firstChildNode as LeafPsiElement).rawReplaceWithText(textIndent + it.firstChildNode.text.trim())
+        templateEntries.forEach { node ->
+            if (!node.text.contains("\n")) {
+                fixFirstTemplateEntries(node, textIndent, actualIndent)
             }
         }
         (templateEntries.last().firstChildNode as LeafPsiElement)
@@ -238,12 +248,43 @@ class IndentationRule(configRules: List<RulesConfig>) : DiktatRule(
                 .trim())
     }
 
+    /**
+     * This method fixes all lines of string template except the last one
+     * Also it considers $foo insertions in string
+     */
+    private fun fixFirstTemplateEntries(
+        node: ASTNode,
+        textIndent: String,
+        actualIndent: Int
+    ) {
+        val correctedText = StringBuilder()
+        // shift of the node depending on its initial string template indent
+        val nodeStartIndent = if (node.firstChildNode.text.takeWhile { it == ' ' }.count() - actualIndent - INDENT_SIZE > 0) {
+            node.firstChildNode.text.takeWhile { it == ' ' }.count() - actualIndent - INDENT_SIZE
+        } else {
+            0
+        }
+        val isPrevStringTemplate = node.treePrev.elementType in stringLiteralTokens
+        val isNextStringTemplate = node.treeNext.elementType in stringLiteralTokens
+        when {
+            // if string template is before literal_string
+            isPrevStringTemplate && !isNextStringTemplate -> correctedText.append(node.firstChildNode.text.trimEnd())
+            // if string template is after literal_string
+            !isPrevStringTemplate && isNextStringTemplate -> correctedText.append(textIndent + " ".repeat(nodeStartIndent) + node.firstChildNode.text.trimStart())
+            // if there is no string template in literal_string
+            !isPrevStringTemplate && !isNextStringTemplate -> correctedText.append(textIndent + " ".repeat(nodeStartIndent) + node.firstChildNode.text.trim())
+            isPrevStringTemplate && isNextStringTemplate -> correctedText.append(node.firstChildNode.text)
+            node.text.isBlank() -> correctedText.append(textIndent)
+            else -> {}
+        }
+        (node.firstChildNode as LeafPsiElement).rawReplaceWithText(correctedText.toString())
+    }
+
     private fun ASTNode.getExceptionalIndentInitiator() = treeParent.let { parent ->
         when (parent.psi) {
             // fixme: custom logic for determining exceptional indent initiator, should be moved elsewhere
-            is KtDotQualifiedExpression ->
-                // get the topmost expression to keep extended indent for the whole chain of dot call expressions
-                parents().takeWhile { it.elementType == DOT_QUALIFIED_EXPRESSION || it.elementType == SAFE_ACCESS_EXPRESSION }.last()
+            // get the topmost expression to keep extended indent for the whole chain of dot call expressions
+            is KtDotQualifiedExpression -> parents().takeWhile { it.elementType == DOT_QUALIFIED_EXPRESSION || it.elementType == SAFE_ACCESS_EXPRESSION }.last()
             is KtIfExpression -> parent.findChildByType(THEN) ?: parent.findChildByType(ELSE) ?: parent
             is KtLoopExpression -> (parent.psi as KtLoopExpression).body?.node ?: parent
             else -> parent
@@ -340,6 +381,7 @@ class IndentationRule(configRules: List<RulesConfig>) : DiktatRule(
         private val increasingTokens = listOf(LPAR, LBRACE, LBRACKET, LONG_TEMPLATE_ENTRY_START)
         private val decreasingTokens = listOf(RPAR, RBRACE, RBRACKET, LONG_TEMPLATE_ENTRY_END)
         private val matchingTokens = increasingTokens.zip(decreasingTokens)
+        private val stringLiteralTokens = listOf(SHORT_STRING_TEMPLATE_ENTRY, LONG_STRING_TEMPLATE_ENTRY)
     }
 }
 


Test patch:
diff --git a/diktat-rules/src/test/resources/test/paragraph3/indentation/IndentationFull1Expected.kt b/diktat-rules/src/test/resources/test/paragraph3/indentation/IndentationFull1Expected.kt
index d1bca4541b..890053ba1f 100644
--- a/diktat-rules/src/test/resources/test/paragraph3/indentation/IndentationFull1Expected.kt
+++ b/diktat-rules/src/test/resources/test/paragraph3/indentation/IndentationFull1Expected.kt
@@ -46,5 +46,23 @@ data class Example(val field1: Type1,
                 .bar()
         }"
     }
+
+    val dockerFileAsText =
+            """
+                    FROM $baseImage
+                COPY resources $resourcesPath
+                    RUN /bin/bash
+            """.trimIndent()
+
+    val some =
+            """
+                          some $foo test
+                  $start another value
+            """.trimIndent()
+
+    val teeest =
+            """
+                  some text $foo $bar another text
+            """.trimIndent()
 }
 
diff --git a/diktat-rules/src/test/resources/test/paragraph3/indentation/IndentationFull1Test.kt b/diktat-rules/src/test/resources/test/paragraph3/indentation/IndentationFull1Test.kt
index 2eb1ab279e..03ca6762d8 100644
--- a/diktat-rules/src/test/resources/test/paragraph3/indentation/IndentationFull1Test.kt
+++ b/diktat-rules/src/test/resources/test/paragraph3/indentation/IndentationFull1Test.kt
@@ -46,4 +46,22 @@ fun foo(
             .bar()
         }"
     }
+
+    val dockerFileAsText =
+                """
+                        FROM $baseImage
+                    COPY resources $resourcesPath
+                        RUN /bin/bash
+                """.trimIndent()
+
+    val some =
+                  """
+                                some $foo test
+                        $start another value
+                  """.trimIndent()
+
+    val teeest =
+                """
+                      some text $foo $bar another text
+                """.trimIndent()
 }
diff --git a/diktat-rules/src/test/resources/test/smoke/src/main/kotlin/Example6Expected.kt b/diktat-rules/src/test/resources/test/smoke/src/main/kotlin/Example6Expected.kt
index 7d19f7fefc..165882843a 100644
--- a/diktat-rules/src/test/resources/test/smoke/src/main/kotlin/Example6Expected.kt
+++ b/diktat-rules/src/test/resources/test/smoke/src/main/kotlin/Example6Expected.kt
@@ -18,3 +18,10 @@ val text =
        x 
     """
 
+val dockerFileAsText =
+        """
+            FROM $baseImage someTest
+            COPY resources $resourcesPath
+            RUN /bin/bash
+        """.trimIndent()  // RUN command shouldn't matter because it will be replaced on container creation
+
diff --git a/diktat-rules/src/test/resources/test/smoke/src/main/kotlin/Example6Test.kt b/diktat-rules/src/test/resources/test/smoke/src/main/kotlin/Example6Test.kt
index 402d258c7d..86cd15e232 100644
--- a/diktat-rules/src/test/resources/test/smoke/src/main/kotlin/Example6Test.kt
+++ b/diktat-rules/src/test/resources/test/smoke/src/main/kotlin/Example6Test.kt
@@ -18,3 +18,9 @@ val text =
        x 
     """
 
+val dockerFileAsText =
+                """
+                    FROM $baseImage someTest
+                    COPY resources $resourcesPath
+                    RUN /bin/bash
+                """.trimIndent()  // RUN command shouldn't matter because it will be replaced on container creation