Abbreviate nested enums (#71)

We can use dot-abbreviation to keep descriptions short but provide
enough context.

Author: stephencelis

Sources/CustomDump/Dump.swift

@@ -58,14 +58,15 @@ public func customDump<T, TargetStream>(
 ) -> T where TargetStream: TextOutputStream {
 
   var idPerItem: [ObjectIdentifier: UInt] = [:]
-  var occurencePerType: [String: UInt] = [:]
+  var occurrencePerType: [String: UInt] = [:]
   var visitedItems: Set<ObjectIdentifier> = []
 
   func customDumpHelp<T, TargetStream>(
     _ value: T,
     to target: inout TargetStream,
     name: String?,
     indent: Int,
+    isRoot: Bool,
     maxDepth: Int
   ) where TargetStream: TextOutputStream {
     if T.self is AnyObject.Type, withUnsafeBytes(of: value, { $0.allSatisfy { $0 == 0 } }) {
@@ -89,7 +90,12 @@ public func customDump<T, TargetStream>(
           var childOut = ""
           let child = mirror.children.first!
           customDumpHelp(
-            child.value, to: &childOut, name: child.label, indent: 0, maxDepth: maxDepth - 1
+            child.value,
+            to: &childOut,
+            name: child.label,
+            indent: 0,
+            isRoot: false,
+            maxDepth: maxDepth - 1
           )
           if childOut.contains("\n") {
             if maxDepth == 0 {
@@ -113,7 +119,13 @@ public func customDump<T, TargetStream>(
           for (offset, var child) in children.enumerated() {
             transform(&child, offset)
             customDumpHelp(
-              child.value, to: &out, name: child.label, indent: 2, maxDepth: maxDepth - 1)
+              child.value,
+              to: &out,
+              name: child.label,
+              indent: 2,
+              isRoot: false,
+              maxDepth: maxDepth - 1
+            )
             if offset != children.count - 1 {
               out.write(",")
             }
@@ -132,16 +144,18 @@ public func customDump<T, TargetStream>(
       out.write(value.customDumpDescription)
 
     case let (value as CustomDumpRepresentable, _):
-      customDumpHelp(value.customDumpValue, to: &out, name: nil, indent: 0, maxDepth: maxDepth - 1)
+      customDumpHelp(
+        value.customDumpValue, to: &out, name: nil, indent: 0, isRoot: false, maxDepth: maxDepth - 1
+      )
 
     case let (value as AnyObject, .class?):
       let item = ObjectIdentifier(value)
-      var occurence = occurencePerType[typeName(mirror.subjectType), default: 0] {
-        didSet { occurencePerType[typeName(mirror.subjectType)] = occurence }
+      var occurrence = occurrencePerType[typeName(mirror.subjectType), default: 0] {
+        didSet { occurrencePerType[typeName(mirror.subjectType)] = occurrence }
       }
 
       var id: String {
-        let id = idPerItem[item, default: occurence]
+        let id = idPerItem[item, default: occurrence]
         idPerItem[item] = id
 
         return id > 1 ? "#\(id)" : ""
@@ -150,7 +164,7 @@ public func customDump<T, TargetStream>(
         out.write("\(typeName(mirror.subjectType))\(id)(↩︎)")
       } else {
         visitedItems.insert(item)
-        occurence += 1
+        occurrence += 1
         var children = Array(mirror.children)
 
         var superclassMirror = mirror.superclassMirror
@@ -192,7 +206,7 @@ public func customDump<T, TargetStream>(
       }
 
     case (_, .enum?):
-      out.write("\(typeName(mirror.subjectType)).")
+      out.write(isRoot ? "\(typeName(mirror.subjectType))." : ".")
       if let child = mirror.children.first {
         let childMirror = Mirror(customDumpReflecting: child.value)
         let associatedValuesMirror =
@@ -215,7 +229,7 @@ public func customDump<T, TargetStream>(
 
     case (_, .optional?):
       if let value = mirror.children.first?.value {
-        customDumpHelp(value, to: &out, name: nil, indent: 0, maxDepth: maxDepth)
+        customDumpHelp(value, to: &out, name: nil, indent: 0, isRoot: false, maxDepth: maxDepth)
       } else {
         out.write("nil")
       }
@@ -266,7 +280,7 @@ public func customDump<T, TargetStream>(
     target.write((name.map { "\($0): " } ?? "").appending(out).indenting(by: indent))
   }
 
-  customDumpHelp(value, to: &target, name: name, indent: indent, maxDepth: maxDepth)
+  customDumpHelp(value, to: &target, name: name, indent: indent, isRoot: true, maxDepth: maxDepth)
   return value
 }
 

Tests/CustomDumpTests/Conformances/FoundationTests.swift

@@ -136,7 +136,7 @@ final class FoundationTests: XCTestCase {
       dump,
       """
       Calendar(
-        identifier: Calendar.Identifier.gregorian,
+        identifier: .gregorian,
         locale: Locale(),
         timeZone: TimeZone(
           identifier: "GMT",

Tests/CustomDumpTests/DumpTests.swift

@@ -242,6 +242,20 @@ final class DumpTests: XCTestCase {
       )
       """
     )
+
+    dump = ""
+    customDump(Nested.nest(.fizz(0.9, buzz: "2")), to: &dump)
+    XCTAssertNoDifference(
+      dump,
+      """
+      Nested.nest(
+        .fizz(
+          0.9,
+          buzz: "2"
+        )
+      )
+      """
+    )
   }
 
   func testOptional() {
@@ -608,7 +622,7 @@ final class DumpTests: XCTestCase {
       dump,
       """
       Result.success(
-        Result.success(42)
+        .success(42)
       )
       """
     )

Tests/CustomDumpTests/Mocks.swift

@@ -41,6 +41,10 @@ enum Enum {
   case fu(bar: Int)
 }
 
+enum Nested {
+  case nest(Enum)
+}
+
 enum Namespaced {
   class Class {
     var x: Int