Implement TrimMultilineRawString

detekt-core/src/main/resources/default-detekt-config.yml

@@ -642,6 +642,8 @@ style:
     excludeGuardClauses: false
   TrailingWhitespace:
     active: false
+  TrimMultilineRawString:
+    active: false
   UnderscoresInNumericLiterals:
     active: false
     acceptableLength: 4

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

@@ -30,6 +30,7 @@ class StyleGuideProvider : DefaultRuleSetProvider {
             DestructuringDeclarationWithTooManyEntries(config),
             ReturnCount(config),
             ThrowsCount(config),
+            TrimMultilineRawString(config),
             NewLineAtEndOfFile(config),
             WildcardImport(config),
             FileParsingRule(config),

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

@@ -0,0 +1,74 @@
+package io.gitlab.arturbosch.detekt.rules.style
+
+import io.gitlab.arturbosch.detekt.api.CodeSmell
+import io.gitlab.arturbosch.detekt.api.Config
+import io.gitlab.arturbosch.detekt.api.Debt
+import io.gitlab.arturbosch.detekt.api.Entity
+import io.gitlab.arturbosch.detekt.api.Issue
+import io.gitlab.arturbosch.detekt.api.Rule
+import io.gitlab.arturbosch.detekt.api.Severity
+import org.jetbrains.kotlin.psi.KtCallExpression
+import org.jetbrains.kotlin.psi.KtExpression
+import org.jetbrains.kotlin.psi.KtStringTemplateExpression
+import org.jetbrains.kotlin.psi.psiUtil.getQualifiedExpressionForReceiver
+import org.jetbrains.kotlin.psi.psiUtil.getQualifiedExpressionForSelectorOrThis
+
+/**
+ * All the Raw strings that have more than one line should be followed by `trimMargin()` or `trimIndent()`.
+ *
+ * <noncompliant>
+ * """
+ *   Hello World!
+ *   How are you?
+ * """
+ * </noncompliant>
+ *
+ * <compliant>
+ * """
+ *   |  Hello World!
+ *   |  How are you?
+ * """.trimMargin()
+ *
+ * """
+ *   Hello World!
+ *   How are you?
+ * """.trimIndent()
+ *
+ * """Hello World! How are you?"""
+ * </compliant>
+ */
+class TrimMultilineRawString(val config: Config) : Rule(config) {
+    override val issue = Issue(
+        javaClass.simpleName,
+        Severity.Style,
+        "Multiline raw strings should be followed by `trimMargin()` or `trimIndent()`.",
+        Debt.FIVE_MINS
+    )
+
+    override fun visitStringTemplateExpression(expression: KtStringTemplateExpression) {
+        super.visitStringTemplateExpression(expression)
+
+        if (expression.text.lines().count() == 1) return
+
+        val nextCall = expression.getQualifiedExpressionForSelectorOrThis()
+            .getQualifiedExpressionForReceiver()
+            ?.selectorExpression
+            ?.asKtCallExpression()
+            ?.calleeExpression
+            ?.text
+
+        if (nextCall !in trimFunctions) {
+            report(
+                CodeSmell(
+                    issue,
+                    Entity.from(expression),
+                    "Multiline raw strings should be followed by `trimMargin()` or `trimIndent()`",
+                )
+            )
+        }
+    }
+}
+
+private fun KtExpression.asKtCallExpression(): KtCallExpression? = this as? KtCallExpression
+
+private val trimFunctions = listOf("trimIndent", "trimMargin")

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

@@ -0,0 +1,87 @@
+@file:Suppress("StringTemplate")
+
+package io.gitlab.arturbosch.detekt.rules.style
+
+import io.gitlab.arturbosch.detekt.api.Config
+import io.gitlab.arturbosch.detekt.test.compileAndLint
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.Test
+
+class TrimMultilineRawStringSpec {
+    val subject = TrimMultilineRawString(Config.empty)
+
+    @Test
+    fun `raises multiline raw strings without trim`() {
+        val code = """
+                val a = ${TQ}
+                Hello world!
+                ${TQ}
+            """
+        subject.compileAndLint(code)
+        assertThat(subject.findings).hasSize(1)
+    }
+
+    @Test
+    fun `raises multiline raw strings with lenght`() {
+        val code = """
+                val a = ${TQ}
+                Hello world!
+                ${TQ}.length
+            """
+        subject.compileAndLint(code)
+        assertThat(subject.findings).hasSize(1)
+    }
+
+    @Test
+    fun `doesn't raise multiline raw strings without trimIndent`() {
+        val code = """
+                val a = ${TQ}
+                Hello world!
+                ${TQ}.trimIndent()
+            """
+        subject.compileAndLint(code)
+        assertThat(subject.findings).isEmpty()
+    }
+
+    @Test
+    fun `doesn't raise multiline raw strings without trimMargin`() {
+        val code = """
+                val a = ${TQ}
+                |Hello world!
+                ${TQ}.trimMargin()
+            """
+        subject.compileAndLint(code)
+        assertThat(subject.findings).isEmpty()
+    }
+
+    @Test
+    fun `doesn't raise multiline raw strings without trimMargin with parameter`() {
+        val code = """
+                val a = ${TQ}
+                >Hello world!
+                ${TQ}.trimMargin(">")
+            """
+        subject.compileAndLint(code)
+        assertThat(subject.findings).isEmpty()
+    }
+
+    @Test
+    fun `don't raise one line raw strings`() {
+        val code = """
+                val a = ${TQ}Hello world!${TQ}
+            """
+        subject.compileAndLint(code)
+        assertThat(subject.findings).isEmpty()
+    }
+
+    @Test
+    fun `doesn't raise if it is not a raw string`() {
+        val code = """
+                val a = "Hello world!"
+            """
+        subject.compileAndLint(code)
+        assertThat(subject.findings).isEmpty()
+    }
+}
+
+private const val TQ = "\"\"\""