refactor(audience): extend Identity with Get + ClearCache, relocate tests to Core/

Adds two methods to Identity that support the SDK's GDPR and
lifecycle needs: Get returns the existing anonymousId without
minting a new one (so GDPR DeleteData doesn't register an id
just to delete it), and ClearCache drops the in-memory cache
without touching disk (so re-Init with a different
persistentDataPath reads the new file instead of returning the
previous session's id).

Relocates the test fixture from Tests/Runtime/IdentityTests.cs to
Tests/Runtime/Core/IdentityTests.cs to mirror Runtime/Core/Identity.cs.
The relocation expands coverage with two new tests for Get
(Get_NoExistingFile_ReturnsNull_AndDoesNotCreate,
Get_ExistingFile_ReturnsPersistedId) and swaps hardcoded
Path.Combine(_testDir, "imtbl_audience", "identity") calls for the
AudiencePaths.IdentityFile helper. The original five tests
(NewDirectory_*, ExistingFile_*, SecondCall_*, Reset_*,
ConsentNone_*) are preserved byte-equivalent modulo the path
helper swap.

Author: ImmutableJeffrey

src/Packages/Audience/Runtime/Core/Identity.cs

@@ -15,6 +15,47 @@ internal sealed class Identity
         private static volatile string _cachedId;
         private static readonly object _sync = new object();
 
+        // Returns the existing anonymous ID, or null if none exists. Never
+        // creates one — use for call sites that must not implicitly register
+        // a new ID (e.g. GDPR deletion).
+        internal static string Get(string persistentDataPath)
+        {
+            if (_cachedId != null) return _cachedId;
+
+            lock (_sync)
+            {
+                if (_cachedId != null) return _cachedId;
+
+                try
+                {
+                    var filePath = AudiencePaths.IdentityFile(persistentDataPath);
+                    if (!File.Exists(filePath)) return null;
+
+                    _cachedId = File.ReadAllText(filePath).Trim();
+                    return _cachedId;
+                }
+                catch (IOException)
+                {
+                    return null;
+                }
+                catch (UnauthorizedAccessException)
+                {
+                    return null;
+                }
+            }
+        }
+
+        // Drops the in-memory cache without touching disk. Called on
+        // Shutdown/ResetState so a subsequent Init with a different
+        // persistentDataPath re-reads the file from the new location.
+        internal static void ClearCache()
+        {
+            lock (_sync)
+            {
+                _cachedId = null;
+            }
+        }
+
         // Returns the anonymous ID, generating and persisting it on first call.
         // Returns null without touching disk when consent is None.
         // Safe to call from any thread after ImmutableAudience.Init() has run on the main thread.

…/Audience/Tests/Runtime/IdentityTests.cs …ence/Tests/Runtime/Core/IdentityTests.cssrc/Packages/Audience/Tests/Runtime/IdentityTests.cs renamed to src/Packages/Audience/Tests/Runtime/Core/IdentityTests.cs src/Packages/Audience/Tests/Runtime/IdentityTests.cs renamed to src/Packages/Audience/Tests/Runtime/Core/IdentityTests.cs

@@ -31,7 +31,7 @@ public void NewDirectory_GeneratesNonEmptyId_AndWritesFile()
             Assert.IsNotNull(id);
             Assert.IsNotEmpty(id);
 
-            var filePath = Path.Combine(_testDir, "imtbl_audience", "identity");
+            var filePath = AudiencePaths.IdentityFile(_testDir);
             Assert.IsTrue(File.Exists(filePath), "identity file should exist on disk");
         }
 
@@ -40,9 +40,9 @@ public void ExistingFile_ReturnsPreviousId_WithoutGeneratingNew()
         {
             // Simulate a returning player by pre-writing an identity file (as a previous launch would have done).
             var expectedId = "pre-existing-id-from-last-launch";
-            var dir = Path.Combine(_testDir, "imtbl_audience");
+            var dir = AudiencePaths.AudienceDir(_testDir);
             Directory.CreateDirectory(dir);
-            File.WriteAllText(Path.Combine(dir, "identity"), expectedId);
+            File.WriteAllText(AudiencePaths.IdentityFile(_testDir), expectedId);
 
             var result = Identity.GetOrCreate(_testDir, ConsentLevel.Anonymous);
 
@@ -76,8 +76,29 @@ public void ConsentNone_ReturnsNull_AndNoFileWritten()
 
             Assert.IsNull(id);
 
-            var filePath = Path.Combine(_testDir, "imtbl_audience", "identity");
+            var filePath = AudiencePaths.IdentityFile(_testDir);
             Assert.IsFalse(File.Exists(filePath), "identity file must not be written when consent is None");
         }
+
+        [Test]
+        public void Get_NoExistingFile_ReturnsNull_AndDoesNotCreate()
+        {
+            var id = Identity.Get(_testDir);
+
+            Assert.IsNull(id);
+            var filePath = AudiencePaths.IdentityFile(_testDir);
+            Assert.IsFalse(File.Exists(filePath), "Get must not create the identity file");
+        }
+
+        [Test]
+        public void Get_ExistingFile_ReturnsPersistedId()
+        {
+            var expectedId = "pre-existing-id";
+            var dir = AudiencePaths.AudienceDir(_testDir);
+            Directory.CreateDirectory(dir);
+            File.WriteAllText(AudiencePaths.IdentityFile(_testDir), expectedId);
+
+            Assert.AreEqual(expectedId, Identity.Get(_testDir));
+        }
     }
 }