Convert multiline strings to string blocks (#6244)

Co-authored-by: SimplyDanny <[email protected]>

Author: Copilot

Tests/BuiltInRulesTests/LineLengthRuleTests.swift

@@ -2,17 +2,25 @@
 import TestHelpers
 
 final class LineLengthRuleTests: SwiftLintTestCase {
+    private static let longString = String(repeating: "a", count: 121)
+
     private let longFunctionDeclarations = [
-        Example("public func superDuperLongFunctionDeclaration(a: String, b: String, " +
-            "c: String, d: String, e: String, f: String, g: String, h: String, i: String, " +
-            "j: String, k: String, l: String, m: String, n: String, o: String, p: String, " +
-            "q: String, r: String, s: String, t: String, u: String, v: String, w: String, " +
-            "x: String, y: String, z: String) {}\n"),
-        Example("func superDuperLongFunctionDeclaration(a: String, b: String, " +
-            "c: String, d: String, e: String, f: String, g: String, h: String, i: String, " +
-            "j: String, k: String, l: String, m: String, n: String, o: String, p: String, " +
-            "q: String, r: String, s: String, t: String, u: String, v: String, w: String, " +
-            "x: String, y: String, z: String) {}\n"),
+        Example("""
+            public func superDuperLongFunctionDeclaration(a: String, b: String, \
+            c: String, d: String, e: String, f: String, g: String, h: String, i: String, \
+            j: String, k: String, l: String, m: String, n: String, o: String, p: String, \
+            q: String, r: String, s: String, t: String, u: String, v: String, w: String, \
+            x: String, y: String, z: String) {}
+
+            """),
+        Example("""
+            func superDuperLongFunctionDeclaration(a: String, b: String, \
+            c: String, d: String, e: String, f: String, g: String, h: String, i: String, \
+            j: String, k: String, l: String, m: String, n: String, o: String, p: String, \
+            q: String, r: String, s: String, t: String, u: String, v: String, w: String, \
+            x: String, y: String, z: String) {}
+
+            """),
         Example("""
             struct S {
                 public init(a: String, b: String, c: String, d: String, e: String, f: String, \
@@ -40,29 +48,49 @@ final class LineLengthRuleTests: SwiftLintTestCase {
 
     private let longComment = Example(String(repeating: "/", count: 121) + "\n")
     private let longBlockComment = Example("/*" + String(repeating: " ", count: 121) + "*/\n")
-    private let longRealBlockComment = Example("/*\n" +
-        String(repeating: "a", count: 121) + "\n" +
-        "*/\n")
+    private let longRealBlockComment = Example("""
+        /*
+        \(LineLengthRuleTests.longString)
+        */
+
+        """)
     private let declarationWithTrailingLongComment = Example("let foo = 1 " + String(repeating: "/", count: 121) + "\n")
     private let interpolatedString = Example("print(\"\\(value)" + String(repeating: "A", count: 113) + "\" )\n")
-    private let plainString = Example("print(\"" + String(repeating: "A", count: 121) + ")\"\n")
-
-    private let multilineString = Example("let multilineString = \"\"\"\n" +
-        String(repeating: "A", count: 121) + "\n" +
-        "\"\"\"\n")
-    private let tripleStringSingleLine = Example("let tripleString = \"\"\""
-        + String(repeating: "A", count: 121) + "\"\"\"\n")
-    private let poundStringSingleLine = Example("let poundString = #\""
-        + String(repeating: "A", count: 121) + "\"#\n")
-    private let multilineStringWithExpression = Example("let multilineString = \"\"\"\n" +
-        String(repeating: "A", count: 121) + "\n\n\"\"\"; let a = 1")
-    private let multilineStringWithNewlineExpression = Example("let multilineString = \"\"\"\n" +
-        String(repeating: "A", count: 121) + "\n\n\"\"\"\n; let a = 1")
-    private let multilineStringFail = Example("let multilineString = \"A\" + \n\"" +
-        String(repeating: "A", count: 121) + "\"\n")
-    private let multilineStringWithFunction = Example("let multilineString = \"\"\"\n" +
-        String(repeating: "A", count: 121) + "\n" +
-        "\"\"\".functionCall()")
+    private let plainString = Example("print(\"" + LineLengthRuleTests.longString + ")\"\n")
+
+    private let multilineString = Example("""
+        let multilineString = \"\"\"
+        \(LineLengthRuleTests.longString)
+        \"\"\"
+
+        """)
+    private let tripleStringSingleLine = Example(
+        "let tripleString = \"\"\"\(LineLengthRuleTests.longString)\"\"\"\n"
+    )
+    private let poundStringSingleLine = Example("let poundString = #\"\(LineLengthRuleTests.longString)\"#\n")
+    private let multilineStringWithExpression = Example("""
+        let multilineString = \"\"\"
+        \(LineLengthRuleTests.longString)
+
+        \"\"\"; let a = 1
+        """)
+    private let multilineStringWithNewlineExpression = Example("""
+        let multilineString = \"\"\"
+        \(LineLengthRuleTests.longString)
+
+        \"\"\"
+        ; let a = 1
+        """)
+    private let multilineStringFail = Example("""
+        let multilineString = "A" +
+        "\(LineLengthRuleTests.longString)"
+
+        """)
+    private let multilineStringWithFunction = Example("""
+        let multilineString = \"\"\"
+        \(LineLengthRuleTests.longString)
+        \"\"\".functionCall()
+        """)
 
     func testLineLength() {
         verifyRule(LineLengthRule.description, commentDoesntViolate: false, stringDoesntViolate: false)