feat: Add cache and retry support

[wenyue]

Introduce the maxRetries and retryInterval in isFirstInstance

[coderabbitai]

📝 Walkthrough

Summary by CodeRabbit

• Refactor
  • Enhanced instance detection with configurable retry mechanism—adjust maximum retries and retry intervals to suit your application needs.
  • Improved error resilience during instance activation with optimized recovery logic.

Pre-merge checks and finishing touches

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The pull request title 'feat: Add cache and retry support' accurately reflects the main changes in the changeset. The AI-generated summary confirms that the PR introduces caching semantics for _isFirstInstance (shifting from bool? to Future?) and adds retry logic with maxRetries and retryInterval parameters to the isFirstInstance method. The title captures both key aspects of the enhancement.
Description check	✅ Passed	The pull request description 'Introduce the maxRetries and retryInterval in isFirstInstance' is directly related to the changeset. It accurately describes a core aspect of the changes—the introduction of configurable retry parameters to the isFirstInstance method. While the description doesn't mention the caching aspect, it is sufficiently related to the changeset and provides meaningful information about the primary enhancement.

✨ Finishing touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

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📜 Recent review details

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📥 Commits

Reviewing files that changed from the base of the PR and between 2d367fc and a4922f5.

📒 Files selected for processing (1)

• lib/flutter_single_instance.dart (4 hunks)

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[coderabbitai]

Actionable comments posted: 2

📜 Review details

Configuration used: CodeRabbit UI

Review profile: ASSERTIVE

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 7162226 and b24dbf0.

📒 Files selected for processing (2)

• lib/flutter_single_instance.dart (4 hunks)
• lib/src/unsupported.dart (1 hunks)

[coderabbitai]

Actionable comments posted: 2

♻️ Duplicate comments (1)

lib/flutter_single_instance.dart (1)

153-172: Loop still performs no retries when maxRetries=1.

With while (attempt < maxRetries) the default maxRetries = 1 yields exactly one attempt and zero retries, which is the same problem previously flagged. Please iterate from the initial attempt through the configured retry count (inclusive) so callers actually get the number of retries they requested.

-      bool result = false;
-      int attempt = 0;
-
-      while (attempt < maxRetries) {
+      bool result = false;
+
+      for (var attempt = 0; attempt <= maxRetries; attempt++) {
         // Wait before retrying (skip for first attempt).
         if (attempt > 0) {
           logger.finest(
               "Retrying activateInstance (attempt $attempt/$maxRetries)");
           await Future.delayed(retryInterval);
         }
 
-        result = await activateInstance(processName);
+        result = await activateInstance(resolvedProcessName);
 
         if (result) {
           break; // Exit loop if activation succeeds.
         }
-
-        attempt++;
       }

📜 Review details

Configuration used: CodeRabbit UI

Review profile: ASSERTIVE

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between a6509f9 and 2d367fc.

📒 Files selected for processing (1)

• lib/flutter_single_instance.dart (4 hunks)

[coderabbitai]

⚠️ Potential issue | 🟠 Major

Replace debug-only asserts with runtime argument validation.

assert disappears in release builds, so bad inputs like maxRetries = 0 reach production and the method never even attempts activation. Please guard these parameters with real checks (e.g., throw ArgumentError) so the runtime contract is enforced outside debug mode.(dart.dev)

-    if (_isFirstInstance != null) {
-      return _isFirstInstance!;
-    }
-
-assert(maxRetries >= 1, 'maxRetries must be greater than or equal to 1');
-assert(retryInterval != Duration.zero, 'retryInterval must be non-zero');
+    if (_isFirstInstance != null) {
+      return _isFirstInstance!;
+    }
+
+    if (maxRetries < 1) {
+      throw ArgumentError.value(
+        maxRetries,
+        'maxRetries',
+        'must be greater than or equal to 1',
+      );
+    }
+    if (retryInterval == Duration.zero) {
+      throw ArgumentError.value(
+        retryInterval,
+        'retryInterval',
+        'must be non-zero',
+      );
+    }

🤖 Prompt for AI Agents

In lib/flutter_single_instance.dart around lines 140 to 141, the code uses
debug-only asserts for validating maxRetries and retryInterval; replace those
asserts with runtime argument validation by throwing ArgumentError (e.g.,
ArgumentError.value) when maxRetries < 1 or retryInterval == Duration.zero,
providing clear messages and parameter names so the contract is enforced in
release builds.

[mcquenji]

Thanks for your contribution!