Do not special format multiline strings with template expressions

Summary: This should help fix the issue raised by #556

Reviewed By: cortinico

Differential Revision: D81201747

fbshipit-source-id: f75c7c449c67eadf2118af94e4939cbb7ced84fc

Author: Nivaldo Bondança

CHANGELOG.md

@@ -13,14 +13,18 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/).
 ## [Unreleased]
 
 ### Changed
+- Updated ShadowJar to 9.0.2 (https://github.com/facebook/ktfmt/pull/555)
+
+### Fixed
+- Do not apply special format handling of multiline strings with template expressions in them (https://github.com/facebook/ktfmt/issues/556)
 
 
 ## [0.57]
 
 ### Added
 - `TrailingCommaManagementStrategy.ONLY_ADD` strategy that does not remove existing trailing commas (https://github.com/facebook/ktfmt/issues/461, https://github.com/facebook/ktfmt/issues/512, https://github.com/facebook/ktfmt/issues/514)
 - Formatting of where clauses (https://github.com/facebook/ktfmt/issues/541)
-- Special format handling of multiline strings with `trimMargin()` and `trimIndent` (https://github.com/facebook/ktfmt/issues/389)
+- Special format handling of multiline strings with `trimMargin()` and `trimIndent()` (https://github.com/facebook/ktfmt/issues/389)
 
 ### Changed
 - `FormattingOptions.manageTrailingCommas` was replaced with `FormattingOptions.trailingCommaManagementStrategy`, which also added new `TrailingCommaManagementStrategy.ONLY_ADD` strategy (https://github.com/facebook/ktfmt/issues/461, https://github.com/facebook/ktfmt/issues/512, https://github.com/facebook/ktfmt/issues/514)

core/src/main/java/com/facebook/ktfmt/format/MultilineStringFormatter.kt

@@ -27,6 +27,7 @@ import org.jetbrains.kotlin.psi.psiUtil.startOffset
  */
 class MultilineStringFormatter(val continuationIndentSize: Int) {
   class Candidate(
+      val isDollarString: Boolean,
       val isMargin: Boolean,
       /* The start offset of the trim method call, right before `.trimX` */
       val trimMethodCallOffset: Int,
@@ -47,8 +48,8 @@ class MultilineStringFormatter(val continuationIndentSize: Int) {
     val candidates = getCandidates(code)
     val result = StringBuilder(code)
 
-    val openTemplateExpressionRegex =
-        Regex("""\$\$?\{(((?<!\\)"([^"]|(\\"))*?[^\\]")|([^\\]'\\?.')|[^"'}])*$""")
+    val simpleTemplateExpressionRegex = Regex("""\${'$'}{1}((\{?[A-Za-z_\s])|\{$)""")
+    val dollarTemplateExpressionRegex = Regex("""\${'$'}{2}((\{?[A-Za-z_\s])|\{$)""")
 
     for (candidate in candidates.sortedByDescending(Candidate::stringOffset)) {
       val (indentCount, lines) =
@@ -59,12 +60,12 @@ class MultilineStringFormatter(val continuationIndentSize: Int) {
         // Single line multiline strings are left alone
         continue
       }
-      if (candidate.isMargin && lines.any { openTemplateExpressionRegex.find(it) != null }) {
-        // Do not mess with multiline template expressions, as those can be a mess
-        // Why?
-        // 1. They span multiple lines
-        // 2. They can be nested recursively
-        // 3. We need to be careful as the closing character ('}') could be inside a string/char
+      val regex =
+          if (candidate.isDollarString) dollarTemplateExpressionRegex
+          else simpleTemplateExpressionRegex
+      if (lines.any { regex.find(it) != null }) {
+        // If there are any template expressions, we cannot format the string as it's possible that
+        // the output of the template affects the result of the trimIndent/trimMargin call
         continue
       }
       val indentation = " ".repeat(indentCount)
@@ -136,14 +137,15 @@ class MultilineStringFormatter(val continuationIndentSize: Int) {
           override fun visitQualifiedExpression(expression: KtQualifiedExpression) {
             val receiver = expression.receiverExpression
             if (receiver !is KtStringTemplateExpression) return
+            val isDollarString = receiver.text.startsWith("$$")
             val selectorExpression = expression.selectorExpression?.text.orEmpty().trim()
             val isTrimMargin = selectorExpression.startsWith("trimMargin(")
             val isTrimIndent = selectorExpression.startsWith("trimIndent(")
             if (isTrimIndent || isTrimMargin) {
               // -1 here to account for the space after the dot
               val trimOffset = checkNotNull(expression.selectorExpression).startOffset - 1
               val stringOffset = receiver.startOffset
-              candidates.add(Candidate(isTrimMargin, trimOffset, stringOffset))
+              candidates.add(Candidate(isDollarString, isTrimMargin, trimOffset, stringOffset))
             }
           }
         }

core/src/test/java/com/facebook/ktfmt/format/FormatterTest.kt

@@ -3259,7 +3259,7 @@ class FormatterTest {
           )
 
   @Test
-  fun `handles multiline trimMargin with multiline template expressions inside of it`() {
+  fun `handles multiline trim with template expressions inside of it`() {
     assertFormatted(
         """
         |val margin =
@@ -3299,7 +3299,7 @@ class FormatterTest {
             |    $TQ
             |   echo hello | wc -c
             |   cat hay_stack.txt | grep needle
-            |   ${'$'}{myList.joinToString("|")}
+            |   {myList.joinToString("|")}
             |    $TQ
             |        .trimMargin()
             |"""
@@ -3311,36 +3311,76 @@ class FormatterTest {
             |    $TQ
             |    |   echo hello | wc -c
             |    |   cat hay_stack.txt | grep needle
-            |    |   ${'$'}{myList.joinToString("|")}$TQ
+            |    |   {myList.joinToString("|")}$TQ
             |        .trimMargin()
             |"""
                 .trimMargin()
         )
   }
 
   @Test
-  fun `handles multiline trimMargin with single-line template expressions`() {
+  fun `handles multiline trim formatting with template expressions`() {
+    assertFormatted(
+        """
+        |val margin1 =
+        |    ${TQ}my math = ${'$'}{ "}" + (1 + 2).toString() }
+        |       | checks
+        |    |    out
+        |        |$TQ
+        |        .trimMargin()
+        |
+        |val margin2 =
+        |    ${"$$"}${TQ}my math = ${"$$"}{ "}" + (1 + 2).toString() }
+        |       | checks
+        |    |    out
+        |        |$TQ
+        |        .trimMargin()
+        |"""
+            .trimMargin()
+    )
+
     assertThatFormatting(
             """
-            |val margin =
-            |    ${TQ}my math = ${'$'}{ "}" + (1 + 2).toString() }
-            |       | checks
-            |    |    out
-            |        |$TQ
-            |        .trimMargin()
-            |"""
+        |val margin1 =
+        |    $TQ
+        |not_a_var$
+        |$1
+        |$\{
+        |$}
+        |$TQ
+        |        .trimIndent()
+        |
+        |val margin2 =
+        |    ${"$$"}$TQ
+        |not_a_var$$
+        |$$1
+        |$$\{
+        |$$}
+        |        |$TQ
+        |        .trimMargin()
+        |"""
                 .trimMargin()
         )
         .isEqualTo(
             """
-            |val margin =
-            |    $TQ
-            |    |my math = ${'$'}{ "}" + (1 + 2).toString() }
-            |    | checks
-            |    |    out
-            |    |$TQ
-            |        .trimMargin()
-            |"""
+        |val margin1 =
+        |    $TQ
+        |    not_a_var$
+        |    $1
+        |    $\{
+        |    $}
+        |    $TQ
+        |        .trimIndent()
+        |
+        |val margin2 =
+        |    ${"$$"}$TQ
+        |    |not_a_var$$
+        |    |$$1
+        |    |$$\{
+        |    |$$}
+        |    |$TQ
+        |        .trimMargin()
+        |"""
                 .trimMargin()
         )
   }