allow string interpolations in log messages

apple · Mar 1, 2019 · 7dd7738 · 7dd7738
1 parent 306f432
commit 7dd7738
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Showing 2 changed files with 14 additions and 1 deletion.
diff --git a/Sources/Logging/Logging.swift b/Sources/Logging/Logging.swift
@@ -214,7 +214,7 @@ extension Logger.MetadataValue: Equatable {
 }
 
 extension Logger {
-    public struct Message: ExpressibleByStringLiteral, Equatable, CustomStringConvertible {
+    public struct Message: ExpressibleByStringLiteral, Equatable, CustomStringConvertible, ExpressibleByStringInterpolation {
         public typealias StringLiteralType = String
 
         private var value: String

diff --git a/Tests/LoggingTests/LoggingTest.swift b/Tests/LoggingTests/LoggingTest.swift
@@ -257,4 +257,17 @@ class LoggingTest: XCTestCase {
         testLogging.history.assertExist(level: .alert, message: "yes")
         testLogging.history.assertExist(level: .emergency, message: "yes")
     }
+
+    func testLogMessageWithStringInterpolation() {
+        let testLogging = TestLogging()
+        LoggingSystem.bootstrapInternal(testLogging.make)
+
+        var logger = Logger(label: "\(#function)")
+        logger.logLevel = .debug
+
+        let someInt = Int.random(in: 23..<42)
+        logger.debug("My favourite number is \(someInt) and not \(someInt - 1)")
+        testLogging.history.assertExist(level: .debug,
+                                        message: "My favourite number is \(someInt) and not \(someInt - 1)" as String)
+    }
 }