Fix false positive MultilineRawStringIndentation with tab indentation

detekt-rules-style/src/main/kotlin/io/gitlab/arturbosch/detekt/rules/style/MultilineRawStringIndentation.kt

@@ -14,8 +14,11 @@ import io.gitlab.arturbosch.detekt.api.SourceLocation
 import io.gitlab.arturbosch.detekt.api.TextLocation
 import io.gitlab.arturbosch.detekt.api.config
 import io.gitlab.arturbosch.detekt.api.internal.Configuration
+import io.gitlab.arturbosch.detekt.rules.safeAs
 import org.jetbrains.kotlin.com.intellij.psi.PsiFile
 import org.jetbrains.kotlin.psi.KtElement
+import org.jetbrains.kotlin.psi.KtLiteralStringTemplateEntry
+import org.jetbrains.kotlin.psi.KtStringTemplateEntry
 import org.jetbrains.kotlin.psi.KtStringTemplateExpression
 
 /**
@@ -63,11 +66,9 @@ class MultilineRawStringIndentation(config: Config) : Rule(config) {
     override fun visitStringTemplateExpression(expression: KtStringTemplateExpression) {
         super.visitStringTemplateExpression(expression)
 
-        val text = expression.text
-        val lineCount = text.lines().count()
-        if (lineCount <= 1) return
-        if (!expression.isTrimmed()) return
-        if (!text.matches(rawStringRegex)) {
+        if (!expression.isRawStringWithLineBreak() || !expression.isTrimmed()) return
+
+        if (!expression.isSurroundedByLineBreaks()) {
             report(
                 CodeSmell(
                     issue,
@@ -79,6 +80,7 @@ class MultilineRawStringIndentation(config: Config) : Rule(config) {
         }
 
         val lineAndColumn = getLineAndColumnInPsiFile(expression.containingFile, expression.textRange) ?: return
+        val lineCount = expression.text.lines().count()
 
         expression.checkIndentation(
             baseIndent = lineAndColumn.lineContent?.countIndent() ?: return,
@@ -167,9 +169,20 @@ private fun message(desiredIntent: Int, currentIndent: Int): String {
     return "The indentation should be $desiredIntent but it is $currentIndent."
 }
 
-private val rawStringRegex = "\"{3}\n(.*\n)? *\"{3}".toRegex(RegexOption.DOT_MATCHES_ALL)
+private fun KtStringTemplateExpression.isSurroundedByLineBreaks(): Boolean {
+    val entries = this.entries
+    return entries.takeWhile { it.isBlankOrLineBreak() }.any { it.text == "\n" } &&
+        entries.takeLastWhile { it.isBlankOrLineBreak() }.any { it.text == "\n" }
+}
+
+private fun KtStringTemplateEntry.isBlankOrLineBreak(): Boolean {
+    val text = safeAs<KtLiteralStringTemplateEntry>()?.text ?: return false
+    return text.all { it.isTabChar() } || text == "\n"
+}
+
+private fun Char.isTabChar() = this == ' ' || this == '\t'
 
-private fun String.countIndent() = this.takeWhile { it == ' ' }.count()
+private fun String.countIndent() = this.takeWhile { it.isTabChar() }.count()
 
 private fun PsiFile.getLine(line: Int): String {
     return text.lineSequence().drop(line - 1).first()

detekt-rules-style/src/main/kotlin/io/gitlab/arturbosch/detekt/rules/style/TrimMultilineRawString.kt

@@ -61,7 +61,7 @@ class TrimMultilineRawString(val config: Config) : Rule(config) {
 }
 
 fun KtStringTemplateExpression.isRawStringWithLineBreak(): Boolean =
-    text.startsWith("\"\"\"") && entries.any {
+    text.startsWith("\"\"\"") && text.endsWith("\"\"\"") && entries.any {
         val literalText = it.safeAs<KtLiteralStringTemplateEntry>()?.text
         literalText != null && "\n" in literalText
     }

detekt-rules-style/src/test/kotlin/io/gitlab/arturbosch/detekt/rules/style/MultilineRawStringIndentationSpec.kt

@@ -1,6 +1,7 @@
 package io.gitlab.arturbosch.detekt.rules.style
 
 import io.gitlab.arturbosch.detekt.api.Config
+import io.gitlab.arturbosch.detekt.test.TestConfig
 import io.gitlab.arturbosch.detekt.test.assertThat
 import io.gitlab.arturbosch.detekt.test.compileAndLint
 import org.junit.jupiter.api.Nested
@@ -310,6 +311,39 @@ class MultilineRawStringIndentationSpec {
             assertThat(subject.findings)
                 .isEmpty()
         }
+
+        @Test
+        fun `don't raise if it has no line breaks`() {
+            val code = """
+                val a = ${TQ}Hello world!$TQ.trimIndent()
+            """.trimIndent()
+            subject.compileAndLint(code)
+            assertThat(subject.findings)
+                .isEmpty()
+        }
+
+        @Test
+        fun `don't raise multiline raw strings if all have the correct indentation - tabs`() {
+            val code = """
+                fun respond(content: String, status: Int) {}
+                fun redirect(accessToken: String, refreshToken: String) {
+                ${TAB}respond(
+                $TAB${TAB}content = $TQ
+                $TAB$TAB$TAB{
+                $TAB$TAB$TAB    "access_token": "${'$'}{accessToken}",
+                $TAB$TAB$TAB    "token_type": "fake_token_type",
+                $TAB$TAB$TAB    "expires_in": 3600,
+                $TAB$TAB$TAB    "refresh_token": "${'$'}{refreshToken}"
+                $TAB$TAB$TAB}
+                $TAB$TAB$TQ.trimIndent(),
+                $TAB${TAB}status = 302
+                $TAB)
+                }
+            """.trimIndent()
+            val subject = MultilineRawStringIndentation(TestConfig(mapOf("indentSize" to 1)))
+            subject.compileAndLint(code)
+            assertThat(subject.findings).isEmpty()
+        }
     }
 
     @Nested
@@ -366,3 +400,4 @@ class MultilineRawStringIndentationSpec {
 }
 
 private const val TQ = "\"\"\""
+private const val TAB = "\t"