impr: Skip evaluating log messages when not logged (#4028)

Skip evaluating log messages the SDK doesn't log. The SDK now only
evaluates log messages when it's actually logging the log message.
Previously, the SDK evaluated all log messages regardless of the log
level. This improves the overall SDK performance slightly.

Author: philipphofmann

CHANGELOG.md

@@ -17,6 +17,7 @@ to receive SIGTERM events, set the option `enableSigtermReporting = true`.
 ### Improvements
 
 - Stop FramesTracker when app is in background (#3979)
+- Skip evaluating log messages when not logged (#4028)
 
 ### Fixes
 

Sentry.xcodeproj/project.pbxproj

@@ -131,6 +131,7 @@
 		62E081AB29ED4322000F69FC /* SentryBreadcrumbTestDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 62E081AA29ED4322000F69FC /* SentryBreadcrumbTestDelegate.swift */; };
 		62E146D02BAAE47600ED34FD /* LocalMetricsAggregator.swift in Sources */ = {isa = PBXBuildFile; fileRef = 62E146CF2BAAE47600ED34FD /* LocalMetricsAggregator.swift */; };
 		62E146D22BAAF55B00ED34FD /* LocalMetricsAggregatorTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 62E146D12BAAF55B00ED34FD /* LocalMetricsAggregatorTests.swift */; };
+		62F05D2B2C0DB1F100916E3F /* SentryLogTestHelper.m in Sources */ = {isa = PBXBuildFile; fileRef = 62F05D2A2C0DB1F100916E3F /* SentryLogTestHelper.m */; };
 		62F226B729A37C120038080D /* SentryBooleanSerialization.m in Sources */ = {isa = PBXBuildFile; fileRef = 62F226B629A37C120038080D /* SentryBooleanSerialization.m */; };
 		62F4DDA12C04CB9700588890 /* SentryBaggageSerializationTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 62F4DDA02C04CB9700588890 /* SentryBaggageSerializationTests.swift */; };
 		62FC69362BEDFF18002D3EF2 /* SentryLogExtensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = 62FC69352BEDFF18002D3EF2 /* SentryLogExtensions.swift */; };
@@ -1111,6 +1112,8 @@
 		62E081AA29ED4322000F69FC /* SentryBreadcrumbTestDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SentryBreadcrumbTestDelegate.swift; sourceTree = "<group>"; };
 		62E146CF2BAAE47600ED34FD /* LocalMetricsAggregator.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LocalMetricsAggregator.swift; sourceTree = "<group>"; };
 		62E146D12BAAF55B00ED34FD /* LocalMetricsAggregatorTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LocalMetricsAggregatorTests.swift; sourceTree = "<group>"; };
+		62F05D292C0DB1C800916E3F /* SentryLogTestHelper.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = SentryLogTestHelper.h; sourceTree = "<group>"; };
+		62F05D2A2C0DB1F100916E3F /* SentryLogTestHelper.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryLogTestHelper.m; sourceTree = "<group>"; };
 		62F226B629A37C120038080D /* SentryBooleanSerialization.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryBooleanSerialization.m; sourceTree = "<group>"; };
 		62F226B829A37C270038080D /* SentryBooleanSerialization.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = SentryBooleanSerialization.h; sourceTree = "<group>"; };
 		62F4DDA02C04CB9700588890 /* SentryBaggageSerializationTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SentryBaggageSerializationTests.swift; sourceTree = "<group>"; };
@@ -3047,6 +3050,8 @@
 				15E0A8EF240F638200F044E3 /* SentrySerializationNilTests.m */,
 				7BA61EA525F21E660008CAA2 /* SentryLogTests.swift */,
 				7BA61EAB25F2206E0008CAA2 /* SentryLog+TestInit.h */,
+				62F05D292C0DB1C800916E3F /* SentryLogTestHelper.h */,
+				62F05D2A2C0DB1F100916E3F /* SentryLogTestHelper.m */,
 				7BBD18BA24530D2600427C76 /* SentryFileManagerTests.swift */,
 				7BD4E8E727FD95900086C410 /* SentryMigrateSessionInitTests.m */,
 				7BD4E8E527FD84480086C410 /* TestFileManagerDelegate.swift */,
@@ -4791,6 +4796,7 @@
 				7BF9EF742722A85B00B5BBEF /* SentryClassRegistrator.m in Sources */,
 				D8F67AF42BE10F9600C9197B /* UIRedactBuilderTests.swift in Sources */,
 				63B819141EC352A7002FDF4C /* SentryInterfacesTests.m in Sources */,
+				62F05D2B2C0DB1F100916E3F /* SentryLogTestHelper.m in Sources */,
 				7B68345128F7EB3D00FB7064 /* SentryMeasurementUnitTests.swift in Sources */,
 				7B14089A248791660035403D /* SentryCrashStackEntryMapperTests.swift in Sources */,
 				D85790292976A69F00C6AC1F /* TestDebugImageProvider.swift in Sources */,

Sources/Sentry/include/SentryLog.h

@@ -22,11 +22,13 @@ SENTRY_NO_INIT
 
 NS_ASSUME_NONNULL_END
 #define SENTRY_LOG(_SENTRY_LOG_LEVEL, ...)                                                         \
-    [SentryLog logWithMessage:[NSString stringWithFormat:@"[%@:%d] %@",                            \
-                                        [[[NSString stringWithUTF8String:__FILE__]                 \
-                                            lastPathComponent] stringByDeletingPathExtension],     \
-                                        __LINE__, [NSString stringWithFormat:__VA_ARGS__]]         \
-                     andLevel:_SENTRY_LOG_LEVEL]
+    if ([SentryLog willLogAtLevel:_SENTRY_LOG_LEVEL]) {                                            \
+        [SentryLog logWithMessage:[NSString stringWithFormat:@"[%@:%d] %@",                        \
+                                            [[[NSString stringWithUTF8String:__FILE__]             \
+                                                lastPathComponent] stringByDeletingPathExtension], \
+                                            __LINE__, [NSString stringWithFormat:__VA_ARGS__]]     \
+                         andLevel:_SENTRY_LOG_LEVEL];                                              \
+    }
 #define SENTRY_LOG_DEBUG(...) SENTRY_LOG(kSentryLevelDebug, __VA_ARGS__)
 #define SENTRY_LOG_INFO(...) SENTRY_LOG(kSentryLevelInfo, __VA_ARGS__)
 #define SENTRY_LOG_WARN(...) SENTRY_LOG(kSentryLevelWarning, __VA_ARGS__)

Tests/SentryTests/Helper/SentryLogTestHelper.h

@@ -0,0 +1,8 @@
+#import "SentryLog.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+void sentryLogDebugWithMacroArgsNotEvaluated(void);
+void sentryLogErrorWithMacro(NSString *message);
+
+NS_ASSUME_NONNULL_END

Tests/SentryTests/Helper/SentryLogTestHelper.m

@@ -0,0 +1,22 @@
+#import "SentryLogTestHelper.h"
+#import <Foundation/Foundation.h>
+#import <XCTest/XCTest.h>
+
+NSString *
+doNotCallMe(void)
+{
+    XCTFail("The args for the log macro must not be evaluated.");
+    return @"Don't call me";
+}
+
+void
+sentryLogDebugWithMacroArgsNotEvaluated(void)
+{
+    SENTRY_LOG_DEBUG(@"%@", doNotCallMe());
+}
+
+void
+sentryLogErrorWithMacro(NSString *message)
+{
+    SENTRY_LOG_ERROR(@"%@", message);
+}

Tests/SentryTests/Helper/SentryLogTests.swift

@@ -69,4 +69,24 @@ class SentryLogTests: XCTestCase {
                         "[Sentry] [info] 3",
                         "[Sentry] [debug] 4"], logOutput.loggedMessages)
     }
+    
+    func testMacroLogsErrorMessage() {
+        let logOutput = TestLogOutput()
+        SentryLog.setLogOutput(logOutput)
+        SentryLog.configure(true, diagnosticLevel: SentryLevel.error)
+        
+        sentryLogErrorWithMacro("error")
+        
+        XCTAssertEqual(["[Sentry] [error] [SentryLogTestHelper:21] error"], logOutput.loggedMessages)
+    }
+    
+    func testMacroDoesNotEvaluateArgs_WhenNotMessageNotLogged() {
+        let logOutput = TestLogOutput()
+        SentryLog.setLogOutput(logOutput)
+        SentryLog.configure(true, diagnosticLevel: SentryLevel.info)
+        
+        sentryLogDebugWithMacroArgsNotEvaluated()
+        
+        XCTAssertTrue(logOutput.loggedMessages.isEmpty)
+    }
 }

Tests/SentryTests/SentryTests-Bridging-Header.h

@@ -139,6 +139,7 @@
 #import "SentryLog+TestInit.h"
 #import "SentryLog.h"
 #import "SentryLogOutput.h"
+#import "SentryLogTestHelper.h"
 #import "SentryMeasurementValue.h"
 #import "SentryMechanism.h"
 #import "SentryMechanismMeta.h"