Merge pull request #2701 from r-plus/bugfix-2700

fix: false positive on sorted_first_last with firstIndex(of:), firstIndex(where:), lastIndex(of:) and lastIndex(where:) method
realm · Apr 2, 2019 · 1d7b37b · 1d7b37b
2 parents 800ca0e + 72dc428
commit 1d7b37b
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diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -57,6 +57,11 @@
   [Dalton Claybrook](https://github.com/daltonclaybrook)
   [#2683](https://github.com/realm/SwiftLint/issues/2683)
 
+* Fix false positives on `sorted_first_last` when calling `firstIndex` and
+  `lastIndex` method.
+  [Taiki Komaba](https://github.com/r-plus)
+  [#2700](https://github.com/realm/SwiftLint/issues/2700)
+
 ## 0.31.0: Busy Laundromat
 
 #### Breaking

diff --git a/Rules.md b/Rules.md
@@ -17577,6 +17577,30 @@ let message = messages.sorted(byKeyPath: #keyPath(Message.timestamp)).last
 let message = messages.sorted(byKeyPath: "timestamp", ascending: false).first
 ```
 
+```swift
+myList.sorted().firstIndex(of: key)
+```
+
+```swift
+myList.sorted().lastIndex(of: key)
+```
+
+```swift
+myList.sorted().firstIndex(where: someFunction)
+```
+
+```swift
+myList.sorted().lastIndex(where: someFunction)
+```
+
+```swift
+myList.sorted().firstIndex { $0 == key }
+```
+
+```swift
+myList.sorted().lastIndex { $0 == key }
+```
+
 </details>
 <details>
 <summary>Triggering Examples</summary>

diff --git a/Source/SwiftLintFramework/Rules/Performance/SortedFirstLastRule.swift b/Source/SwiftLintFramework/Rules/Performance/SortedFirstLastRule.swift
@@ -17,7 +17,13 @@ public struct SortedFirstLastRule: CallPairRule, OptInRule, ConfigurationProvide
             "let max = myList.max()\n",
             "let max = myList.max(by: { $0 < $1 })\n",
             "let message = messages.sorted(byKeyPath: #keyPath(Message.timestamp)).last",
-            "let message = messages.sorted(byKeyPath: \"timestamp\", ascending: false).first"
+            "let message = messages.sorted(byKeyPath: \"timestamp\", ascending: false).first",
+            "myList.sorted().firstIndex(of: key)",
+            "myList.sorted().lastIndex(of: key)",
+            "myList.sorted().firstIndex(where: someFunction)",
+            "myList.sorted().lastIndex(where: someFunction)",
+            "myList.sorted().firstIndex { $0 == key }",
+            "myList.sorted().lastIndex { $0 == key }"
         ],
         triggeringExamples: [
             "↓myList.sorted().first\n",
@@ -38,7 +44,7 @@ public struct SortedFirstLastRule: CallPairRule, OptInRule, ConfigurationProvide
 
     public func validate(file: File) -> [StyleViolation] {
         return validate(file: file,
-                        pattern: "[\\}\\)]\\s*\\.(first|last)",
+                        pattern: "[\\}\\)]\\s*\\.(first|last)(?!Index)",
                         patternSyntaxKinds: [.identifier],
                         callNameSuffix: ".sorted",
                         severity: configuration.severity) { dictionary in