From 60796c2e8925287d37d05c505ac96a021b60cf5a Mon Sep 17 00:00:00 2001
From: Nick Lockwood <nick@charcoaldesign.co.uk>
Date: Wed, 29 Jul 2020 16:11:07 +0100
Subject: [PATCH] Take maxwidth into account when unwrapping braces

---
 Sources/Rules.swift    | 17 ++++++++++++++++-
 Tests/RulesTests.swift |  2 +-
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/Sources/Rules.swift b/Sources/Rules.swift
index ecd4e8ee..3d96135b 100644
--- a/Sources/Rules.swift
+++ b/Sources/Rules.swift
@@ -1399,7 +1399,7 @@ public struct _FormatRules {
     public let braces = FormatRule(
         help: "Wrap braces in accordance with selected style (K&R or Allman).",
         options: ["allman"],
-        sharedOptions: ["linebreaks"]
+        sharedOptions: ["linebreaks", "maxwidth", "indent", "tabwidth"]
     ) { formatter in
         formatter.forEach(.startOfScope("{")) { i, _ in
             guard let closingBraceIndex = formatter.endOfScope(at: i),
@@ -1442,6 +1442,21 @@ public struct _FormatRules {
                     !formatter.tokens[prevIndex].isComment else {
                     return
                 }
+                let maxWidth = formatter.options.maxWidth
+                if maxWidth == 0 {
+                    // Check that brace doesn't have inline content after it
+                    guard formatter.next(.nonSpace, after: i)?.isLinebreak == true else {
+                        return
+                    }
+                } else {
+                    // Check that unwrapping wouldn't exceed line length
+                    let endOfLine = formatter.endOfLine(at: i)
+                    let length = formatter.lineLength(from: i, upTo: endOfLine)
+                    let prevLineLength = formatter.lineLength(at: prevIndex)
+                    guard prevLineLength + length + 1 <= maxWidth else {
+                        return
+                    }
+                }
                 formatter.replaceTokens(inRange: prevIndex + 1 ..< i, with: [.space(" ")])
             }
         }
diff --git a/Tests/RulesTests.swift b/Tests/RulesTests.swift
index e68443b5..bdb9cbd5 100644
--- a/Tests/RulesTests.swift
+++ b/Tests/RulesTests.swift
@@ -8082,7 +8082,7 @@ class RulesTests: XCTestCase {
                 true
             }
         """
-        let options = FormatOptions(allmanBraces: true, maxWidth: 20)
+        let options = FormatOptions(maxWidth: 20)
         testFormatting(for: input, [output, output2], rules: [FormatRules.wrap], options: options)
     }