added custom reporters: xcode (default), json, csv. fixes #42

CHANGELOG.md

@@ -35,6 +35,12 @@
 * Violations are now printed to stderr.  
   [Keith Smiley](https://github.com/keith)
 
+* Custom reporters are now supported. Specify a value for the `reporter:` key in
+  your configuration file. Available reporters are `xcode` (default), `json`,
+  `csv`.  
+  [JP Simard](https://github.com/jpsim)
+  [#42](https://github.com/realm/SwiftLint/issues/42)
+
 ##### Bug Fixes
 
 * Improve performance of `TrailingWhitespaceRule`.  

Source/SwiftLintFramework/Configuration.swift

@@ -18,15 +18,33 @@ public struct Configuration {
     public let disabledRules: [String] // disabled_rules
     public let included: [String]      // included
     public let excluded: [String]      // excluded
+    public let reporter: String        // reporter (xcode, json, csv)
 
     public var rules: [Rule] {
         return allRules.filter { !disabledRules.contains($0.identifier) }
     }
 
-    public init?(disabledRules: [String] = [], included: [String] = [], excluded: [String] = []) {
+    public var reporterFromString: Reporter.Type {
+        switch reporter {
+        case XcodeReporter.identifier:
+            return XcodeReporter.self
+        case JSONReporter.identifier:
+            return JSONReporter.self
+        case CSVReporter.identifier:
+            return CSVReporter.self
+        default:
+            fatalError("no reporter with identifier '\(reporter)' available.")
+        }
+    }
+
+    public init?(disabledRules: [String] = [],
+                 included: [String] = [],
+                 excluded: [String] = [],
+                 reporter: String = "xcode") {
         self.disabledRules = disabledRules
         self.included = included
         self.excluded = excluded
+        self.reporter = reporter
 
         // Validate that all rule identifiers map to a defined rule
 
@@ -67,7 +85,8 @@ public struct Configuration {
         self.init(
             disabledRules: yamlConfig["disabled_rules"].arrayOfStrings ?? [],
             included: yamlConfig["included"].arrayOfStrings ?? [],
-            excluded: yamlConfig["excluded"].arrayOfStrings ?? []
+            excluded: yamlConfig["excluded"].arrayOfStrings ?? [],
+            reporter: yamlConfig["reporter"].string ?? XcodeReporter.identifier
         )
     }
 

Source/SwiftLintFramework/Linter.swift

@@ -12,8 +12,8 @@ import SourceKittenFramework
 
 public struct Linter {
     private let file: File
-
     private let rules: [Rule]
+    private let reporter: Reporter.Type
 
     public var styleViolations: [StyleViolation] {
         let regions = file.regions()
@@ -29,6 +29,10 @@ public struct Linter {
         }
     }
 
+    public func generateReport() -> String {
+        return reporter.generateReport(styleViolations)
+    }
+
     public var ruleExamples: [RuleExample] {
         return rules.flatMap { $0.example }
     }
@@ -41,5 +45,6 @@ public struct Linter {
     public init(file: File, configuration: Configuration = Configuration()!) {
         self.file = file
         rules = configuration.rules
+        reporter = configuration.reporterFromString
     }
 }

Source/SwiftLintFramework/Reporter.swift

@@ -0,0 +1,12 @@
+//
+//  Reporter.swift
+//  SwiftLint
+//
+//  Created by JP Simard on 9/19/15.
+//  Copyright © 2015 Realm. All rights reserved.
+//
+
+public protocol Reporter: CustomStringConvertible {
+    static var identifier: String { get }
+    static func generateReport(violations: [StyleViolation]) -> String
+}

Source/SwiftLintFramework/Reporters/CSVReporter.swift

@@ -0,0 +1,41 @@
+//
+//  CSVReporter.swift
+//  SwiftLint
+//
+//  Created by JP Simard on 9/19/15.
+//  Copyright © 2015 Realm. All rights reserved.
+//
+
+import Foundation
+
+public struct CSVReporter: Reporter {
+    public static let identifier = "csv"
+
+    public var description: String {
+        return "Reports violations as a newline-separated string of comma-separated values (CSV)."
+    }
+
+    public static func generateReport(violations: [StyleViolation]) -> String {
+        let keys = [
+            "file",
+            "line",
+            "character",
+            "severity",
+            "type",
+            "reason"
+        ]
+        return (keys + violations.flatMap(arrayForViolation)).joinWithSeparator(",")
+    }
+
+    private static func arrayForViolation(violation: StyleViolation) -> [String] {
+        let values: [AnyObject?] = [
+            violation.location.file,
+            violation.location.line,
+            violation.location.character,
+            violation.severity.rawValue,
+            violation.type.description,
+            violation.reason
+        ]
+        return values.map({ $0?.description ?? "" })
+    }
+}

Source/SwiftLintFramework/Reporters/JSONReporter.swift

@@ -0,0 +1,33 @@
+//
+//  JSONReporter.swift
+//  SwiftLint
+//
+//  Created by JP Simard on 9/19/15.
+//  Copyright © 2015 Realm. All rights reserved.
+//
+
+import Foundation
+import SourceKittenFramework
+
+public struct JSONReporter: Reporter {
+    public static let identifier = "json"
+
+    public var description: String {
+        return "Reports violations as a JSON array."
+    }
+
+    public static func generateReport(violations: [StyleViolation]) -> String {
+        return toJSON(violations.map(dictionaryForViolation))
+    }
+
+    private static func dictionaryForViolation(violation: StyleViolation) -> NSDictionary {
+        return [
+            "file": violation.location.file ?? NSNull(),
+            "line": violation.location.line ?? NSNull(),
+            "character": violation.location.character ?? NSNull(),
+            "severity": violation.severity.rawValue,
+            "type": violation.type.description,
+            "reason": violation.reason ?? NSNull()
+        ]
+    }
+}

Source/SwiftLintFramework/Reporters/XcodeReporter.swift

@@ -0,0 +1,27 @@
+//
+//  XcodeReporter.swift
+//  SwiftLint
+//
+//  Created by JP Simard on 9/19/15.
+//  Copyright © 2015 Realm. All rights reserved.
+//
+
+public struct XcodeReporter: Reporter {
+    public static let identifier = "xcode"
+
+    public var description: String {
+        return "Reports violations in the format Xcode uses to display in the IDE. (default)"
+    }
+
+    public static func generateReport(violations: [StyleViolation]) -> String {
+        return violations.map(generateForSingleViolation).joinWithSeparator("\n")
+    }
+
+    internal static func generateForSingleViolation(violation: StyleViolation) -> String {
+        // {full_path_to_file}{:line}{:character}: {error,warning}: {content}
+        return "\(violation.location): " +
+            "\(violation.severity.rawValue.lowercaseString): " +
+            "\(violation.type) Violation: " +
+            (violation.reason ?? "")
+    }
+}

Source/SwiftLintFramework/StyleViolation.swift

@@ -12,11 +12,7 @@ public struct StyleViolation: CustomStringConvertible, Equatable {
     public let location: Location
     public let reason: String?
     public var description: String {
-        // {full_path_to_file}{:line}{:character}: {error,warning}: {content}
-        return "\(location): " +
-            "\(severity.rawValue.lowercaseString): " +
-            "\(type) Violation (\(severity) Severity): " +
-            (reason ?? "")
+        return XcodeReporter.generateForSingleViolation(self)
     }
 
     public init(type: StyleViolationType, location: Location, reason: String? = nil) {

Source/SwiftLintFrameworkTests/ConfigurationTests.swift

@@ -27,6 +27,8 @@ class ConfigurationTests: XCTestCase {
         XCTAssertEqual(config.disabledRules, [])
         XCTAssertEqual(config.included, [])
         XCTAssertEqual(config.excluded, [])
+        XCTAssertEqual(config.reporter, "xcode")
+        XCTAssertEqual(config.reporterFromString.identifier, "xcode")
     }
 
     func testDisabledRules() {

Source/SwiftLintFrameworkTests/ReporterTests.swift

@@ -0,0 +1,66 @@
+//
+//  ReporterTests.swift
+//  SwiftLint
+//
+//  Created by JP Simard on 9/19/15.
+//  Copyright © 2015 Realm. All rights reserved.
+//
+
+import SwiftLintFramework
+import XCTest
+
+class ReporterTests: XCTestCase {
+    func generateViolations() -> [StyleViolation] {
+        return [
+            StyleViolation(type: .Length,
+                location: Location(file: "filename", line: 1, character: 2),
+                severity: .Warning,
+                reason: "Violation Reason."),
+            StyleViolation(type: .Length,
+                location: Location(file: "filename", line: 1, character: 2),
+                severity: .Error,
+                reason: "Violation Reason.")
+        ]
+    }
+
+    func testXcodeReporter() {
+        XCTAssertEqual(
+            XcodeReporter.generateReport(generateViolations()),
+            "filename:1:2: warning: Length Violation: Violation Reason.\n" +
+            "filename:1:2: error: Length Violation: Violation Reason."
+        )
+    }
+
+    func testJSONReporter() {
+        XCTAssertEqual(
+            JSONReporter.generateReport(generateViolations()),
+            "[\n" +
+                "  {\n" +
+                "    \"type\" : \"Length\",\n" +
+                "    \"line\" : 1,\n" +
+                "    \"reason\" : \"Violation Reason.\",\n" +
+                "    \"file\" : \"filename\",\n" +
+                "    \"character\" : 2,\n" +
+                "    \"severity\" : \"Warning\"\n" +
+                "  },\n" +
+                "  {\n" +
+                "    \"type\" : \"Length\",\n" +
+                "    \"line\" : 1,\n" +
+                "    \"reason\" : \"Violation Reason.\",\n" +
+                "    \"file\" : \"filename\",\n" +
+                "    \"character\" : 2,\n" +
+                "    \"severity\" : \"Error\"\n" +
+                "  }\n" +
+            "]"
+        )
+    }
+
+    func testCSVReporter() {
+        XCTAssertEqual(
+            CSVReporter.generateReport(generateViolations()),
+            "file,line,character,severity,type,reason," +
+            "filename,1,2,Warning,Length,Violation Reason.," +
+            "filename,1,2,Error,Length,Violation Reason."
+        )
+    }
+}

Source/swiftlint/LintCommand.swift

@@ -30,7 +30,7 @@ struct LintCommand: CommandType {
                 if let stdinString = stdinNSString as? String {
                     let file = File(contents: stdinString)
                     let linter = Linter(file: file, configuration: configuration)
-                    print(linter.styleViolations.map({ $0.description }).joinWithSeparator("\n"))
+                    print(linter.generateReport())
                     return .Success()
                 }
                 return .Failure(CommandantError<()>.CommandError())