Add breaks around conditions of while-stmt.

This aligns the behavior of while-stmt and if-stmt conditions. The while-stmt conditions didn't have open-breaks, which meant there was no additional indentation nor would continuation breaks be able to stack.

This can result in exceeding the max line length if a while-stmt has a label and first condition, up to its first break, that exceeds the remaining line length.

Author: dylansturg

Sources/SwiftFormatPrettyPrint/TokenStreamCreator.swift

@@ -526,6 +526,19 @@ fileprivate final class TokenStreamCreator: SyntaxVisitor {
     after(node.labelColon, tokens: .space)
     after(node.whileKeyword, tokens: .space)
 
+    // Add break groups, using open continuation breaks, around any conditions after the first so
+    // that continuations inside of the conditions can stack in addition to continuations between
+    // the conditions. There are no breaks around the first condition because there was historically
+    // not break after the while token and adding such a break would cause excessive changes to
+    // previously formatted code.
+    // This has the side effect that the label + `while` + tokens up to the first break in the first
+    // condition could be longer than the column limit since there are no breaks between the label
+    // or while token.
+    for condition in node.conditions.dropFirst() {
+      before(condition.firstToken, tokens: .break(.open(kind: .continuation), size: 0))
+      after(condition.lastToken, tokens: .break(.close(mustBreak: false), size: 0))
+    }
+
     arrangeBracesAndContents(of: node.body, contentsKeyPath: \.statements)
 
     return .visitChildren

Tests/SwiftFormatPrettyPrintTests/WhileStmtTests.swift

@@ -63,6 +63,11 @@ final class WhileStmtTests: PrettyPrintTestCase {
         let a = 123
         var b = "abc"
       }
+      myLabel: while myVeryLongFirstCondition && condition2 || condition3
+      {
+        let a = 123
+        var b = "abc"
+      }
       """
 
     let expected =
@@ -83,6 +88,55 @@ final class WhileStmtTests: PrettyPrintTestCase {
         let a = 123
         var b = "abc"
       }
+      myLabel: while myVeryLongFirstCondition
+        && condition2 || condition3
+      {
+        let a = 123
+        var b = "abc"
+      }
+
+      """
+
+    assertPrettyPrintEqual(input: input, expected: expected, linelength: 29)
+  }
+
+  func testWhileLoopMultipleConditionElements() {
+    let input =
+      """
+      while x >= 0 && y >= 0 && x < foo && y < bar, let object = foo.value(at: y), let otherObject = foo.value(at: x), isEqual(a, b) {
+        foo()
+      }
+      while x >= 0 && y >= 0
+      && x < foo && y < bar,
+      let object =
+      foo.value(at: y),
+      let otherObject = foo.value(at: x), isEqual(a, b) {
+        foo()
+      }
+      """
+
+    let expected =
+      """
+      while x >= 0 && y >= 0
+        && x < foo && y < bar,
+        let object = foo.value(
+          at: y),
+        let otherObject =
+          foo.value(at: x),
+        isEqual(a, b)
+      {
+        foo()
+      }
+      while x >= 0 && y >= 0
+        && x < foo && y < bar,
+        let object =
+          foo.value(at: y),
+        let otherObject =
+          foo.value(at: x),
+        isEqual(a, b)
+      {
+        foo()
+      }
 
       """
 

Tests/SwiftFormatPrettyPrintTests/XCTestManifests.swift

@@ -493,6 +493,7 @@ extension NewlineTests {
     static let __allTests__NewlineTests = [
         ("testLeadingNewlines", testLeadingNewlines),
         ("testLeadingNewlinesWithComments", testLeadingNewlinesWithComments),
+        ("testNewlinesBetweenMembers", testNewlinesBetweenMembers),
         ("testTrailingNewlines", testTrailingNewlines),
         ("testTrailingNewlinesWithComments", testTrailingNewlinesWithComments),
     ]
@@ -802,6 +803,7 @@ extension WhileStmtTests {
     static let __allTests__WhileStmtTests = [
         ("testBasicWhileLoops", testBasicWhileLoops),
         ("testLabeledWhileLoops", testLabeledWhileLoops),
+        ("testWhileLoopMultipleConditionElements", testWhileLoopMultipleConditionElements),
     ]
 }