From f0804fa51c14dcffe2ce576bbcbe52b28c8bffe6 Mon Sep 17 00:00:00 2001
From: JP Simard <jp@jpsim.com>
Date: Wed, 7 Dec 2016 16:24:54 -0800
Subject: [PATCH] fix some false positives in detecting for initializers

in function_parameter_count
---
 .../Rules/FunctionParameterCountRule.swift    | 29 ++++++++++++-------
 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/Source/SwiftLintFramework/Rules/FunctionParameterCountRule.swift b/Source/SwiftLintFramework/Rules/FunctionParameterCountRule.swift
index 768e16581..77867fb68 100644
--- a/Source/SwiftLintFramework/Rules/FunctionParameterCountRule.swift
+++ b/Source/SwiftLintFramework/Rules/FunctionParameterCountRule.swift
@@ -20,6 +20,7 @@ public struct FunctionParameterCountRule: ASTRule, ConfigurationProviderRule {
         description: "Number of function parameters should be low.",
         nonTriggeringExamples: [
             "init(a: Int, b: Int, c: Int, d: Int, e: Int, f: Int) {}",
+            "init (a: Int, b: Int, c: Int, d: Int, e: Int, f: Int) {}",
             "`init`(a: Int, b: Int, c: Int, d: Int, e: Int, f: Int) {}",
             "init?(a: Int, b: Int, c: Int, d: Int, e: Int, f: Int) {}",
             "func f2(p1: Int, p2: Int) { }",
@@ -29,6 +30,7 @@ public struct FunctionParameterCountRule: ASTRule, ConfigurationProviderRule {
         ],
         triggeringExamples: [
             "func f(a: Int, b: Int, c: Int, d: Int, e: Int, f: Int) {}",
+            "func initialValue(a: Int, b: Int, c: Int, d: Int, e: Int, f: Int) {}",
             "func f(a: Int, b: Int, c: Int, d: Int, e: Int, f: Int = 2, g: Int) {}",
             "struct Foo {\n" +
                 "init(a: Int, b: Int, c: Int, d: Int, e: Int, f: Int) {}\n" +
@@ -44,16 +46,17 @@ public struct FunctionParameterCountRule: ASTRule, ConfigurationProviderRule {
 
         let nameOffset = Int(dictionary["key.nameoffset"] as? Int64 ?? 0)
         let length = Int(dictionary["key.namelength"] as? Int64 ?? 0)
-        let substructure = dictionary["key.substructure"] as? [SourceKitRepresentable] ?? []
 
         if functionIsInitializer(file, offset: nameOffset, length: length) {
             return []
         }
 
+        let substructure = dictionary["key.substructure"] as? [SourceKitRepresentable] ?? []
+
         let minThreshold = configuration.params.map({ $0.value }).min(by: <)
 
-        let allParameterCount =
-            allFunctionParameterCount(substructure, offset: nameOffset, length: length)
+        let allParameterCount = allFunctionParameterCount(substructure, offset: nameOffset,
+                                                          length: length)
         if allParameterCount < minThreshold! {
             return []
         }
@@ -74,7 +77,7 @@ public struct FunctionParameterCountRule: ASTRule, ConfigurationProviderRule {
     }
 
     fileprivate func allFunctionParameterCount(_ structure: [SourceKitRepresentable],
-                                           offset: Int, length: Int) -> Int {
+                                               offset: Int, length: Int) -> Int {
         var parameterCount = 0
         for substructure in structure {
             guard let subDict = substructure as? [String: SourceKitRepresentable],
@@ -95,18 +98,22 @@ public struct FunctionParameterCountRule: ASTRule, ConfigurationProviderRule {
     }
 
     fileprivate func defaultFunctionParameterCount(_ file: File, offset: Int, length: Int) -> Int {
-        let equalCharacter = Character("=")
-        return (file.contents as NSString)
-            .substringWithByteRange(start: offset, length: length)?
-            .characters.filter { $0 == equalCharacter }.count ?? 0
+        return file.contents.substringWithByteRange(start: offset, length: length)?
+            .characters.filter { $0 == "=" }.count ?? 0
     }
 
     fileprivate func functionIsInitializer(_ file: File, offset: Int, length: Int) -> Bool {
-        if let function = (file.contents as NSString)
-            .substringWithByteRange(start: offset, length: length), function.hasPrefix("init") {
+        guard let name = file.contents.substringWithByteRange(start: offset, length: length),
+            name.hasPrefix("init"),
+            let funcName = name.components(separatedBy: "(").first else {
+            return false
+        }
+        if funcName == "init" { // fast path
             return true
         }
-        return false
+        let nonAlphas = CharacterSet.alphanumerics.inverted
+        let alphaNumericName = funcName.components(separatedBy: nonAlphas).joined()
+        return alphaNumericName == "init"
     }
 
     fileprivate let functionKinds: [SwiftDeclarationKind] = [