Add tests for SourceEditor.Cache

Author: intitni

TestPlan.xctestplan

@@ -133,6 +133,13 @@
         "identifier" : "FocusedCodeFinderTests",
         "name" : "FocusedCodeFinderTests"
       }
+    },
+    {
+      "target" : {
+        "containerPath" : "container:Tool",
+        "identifier" : "XcodeInspectorTests",
+        "name" : "XcodeInspectorTests"
+      }
     }
   ],
   "version" : 1

Tool/Package.swift

@@ -175,6 +175,8 @@ let package = Package(
             ]
         ),
 
+        .testTarget(name: "XcodeInspectorTests", dependencies: ["XcodeInspector"]),
+
         .target(name: "UserDefaultsObserver"),
 
         .target(

Tool/Sources/XcodeInspector/SourceEditor.swift

@@ -121,12 +121,24 @@ extension SourceEditor {
         private var sourceSelectedTextRange: ClosedRange<Int>?
         private var cachedSelections = [CursorRange]()
 
+        init(
+            sourceContent: String? = nil,
+            cachedLines: [String] = [String](),
+            sourceSelectedTextRange: ClosedRange<Int>? = nil,
+            cachedSelections: [CursorRange] = [CursorRange]()
+        ) {
+            self.sourceContent = sourceContent
+            self.cachedLines = cachedLines
+            self.sourceSelectedTextRange = sourceSelectedTextRange
+            self.cachedSelections = cachedSelections
+        }
+
         func get(content: String, selectedTextRange: ClosedRange<Int>?) -> (
             lines: [String],
             selections: [CursorRange]
         ) {
             Self.queue.sync {
-                let contentMatch = content.hashValue == sourceContent?.hashValue
+                let contentMatch = content == sourceContent
                 let selectedRangeMatch = selectedTextRange == sourceSelectedTextRange
                 let lines: [String] = {
                     if contentMatch {

Tool/Tests/XcodeInspectorTests/SourceEditorCachePerformanceTests.swift

@@ -0,0 +1,23 @@
+import Foundation
+import XCTest
+
+@testable import XcodeInspector
+
+class SourceEditorCachePerformanceTests: XCTestCase {
+    func test_source_editor_cache_get_content_comparison() {
+        let content = String(repeating: """
+        struct Cat: Animal {
+          var name: String
+        }
+
+        """, count: 500)
+        let cache = SourceEditor.Cache(sourceContent: content + "Yes")
+
+        measure {
+            for _ in 1 ... 10000 {
+                _ = cache.get(content: content, selectedTextRange: nil)
+            }
+        }
+    }
+}
+

Tool/Tests/XcodeInspectorTests/SourceEditorCacheTests.swift

@@ -0,0 +1,45 @@
+import Foundation
+import XCTest
+
+@testable import XcodeInspector
+
+class SourceEditorCacheTests: XCTestCase {
+    func test_source_editor_cache_get_content_thread_safe() {
+        func randomContent() -> String {
+            String(repeating: """
+            struct Cat: Animal {
+              var name: String
+            }
+
+            """, count: Int.random(in: 2...10))
+        }
+
+        func randomSelectionRange() -> ClosedRange<Int> {
+            let random = Int.random(in: 0...20)
+            return random...random
+        }
+
+        let cache = SourceEditor.Cache()
+
+        let max = 5000
+        let exp = expectation(description: "test_source_editor_cache_get_content_thread_safe")
+        DispatchQueue.concurrentPerform(iterations: max) { count in
+            let content = randomContent()
+            let selectionRange = randomSelectionRange()
+            let result = cache.get(content: content, selectedTextRange: selectionRange)
+
+            XCTAssertEqual(result.lines, content.breakLines(appendLineBreakToLastLine: false))
+            XCTAssertEqual(result.selections, [SourceEditor.convertRangeToCursorRange(
+                selectionRange,
+                in: result.lines
+            )])
+            
+            if max == count + 1 {
+                exp.fulfill()
+            }
+        }
+        
+        wait(for: [exp], timeout: 10)
+    }
+}
+