[vbreuss]

This PR reduces runtime allocations in Mockolate’s property and indexer access paths by removing LINQ/predicate usage and inlining property setup resolution logic into the interaction handlers.

Key Changes:

• Replaced indexer setup lookup via FirstOrDefault(predicate) with an allocation-free loop-based matcher.
• Inlined property setup retrieval/initialization logic into GetProperty/SetProperty to avoid delegate-related allocations.
• Removed now-unused helper methods/usings related to the previous setup lookup approach.

---

• Part of Performance comparison to Imposter #518

[github-actions]

🚀 Benchmark Results

Details

BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.4 LTS (Noble Numbat)

AMD EPYC 7763 2.61GHz, 1 CPU, 4 logical and 2 physical cores

.NET SDK 10.0.201

[Host] : .NET 10.0.5 (10.0.5, 10.0.526.15411), X64 RyuJIT x86-64-v3
Job=InProcess  Toolchain=InProcessEmitToolchain  IterationCount=15

LaunchCount=1  WarmupCount=10

Method	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Allocated	Alloc Ratio
Indexer_Mockolate	946.7 ns	5.71 ns	4.46 ns	1.00	0.01	0.1898	0.0010	3.1 KB	1.00
Indexer_Moq	191,484.8 ns	713.99 ns	667.87 ns	202.26	1.15	0.7324	0.4883	14.57 KB	4.70
Indexer_NSubstitute	6,387.5 ns	30.09 ns	28.15 ns	6.75	0.04	0.5722	-	9.41 KB	3.04
Indexer_FakeItEasy	6,339.7 ns	32.60 ns	28.90 ns	6.70	0.04	0.4883	0.0153	8.03 KB	2.59
Indexer_Imposter	802.5 ns	13.05 ns	12.21 ns	0.85	0.01	0.2928	0.0048	4.8 KB	1.55

Details

BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.4 LTS (Noble Numbat)

AMD EPYC 7763 2.61GHz, 1 CPU, 4 logical and 2 physical cores

.NET SDK 10.0.201

[Host] : .NET 10.0.5 (10.0.5, 10.0.526.15411), X64 RyuJIT x86-64-v3
Job=InProcess  Toolchain=InProcessEmitToolchain  IterationCount=15

LaunchCount=1  WarmupCount=10

Method	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Allocated	Alloc Ratio
Method_Mockolate	735.5 ns	6.06 ns	5.38 ns	1.00	0.01	0.1307	-	2.14 KB	1.00
Method_Moq	192,710.5 ns	461.18 ns	431.39 ns	262.01	1.93	0.7324	0.4883	14.59 KB	6.82
Method_NSubstitute	6,274.4 ns	26.81 ns	23.77 ns	8.53	0.07	0.5493	0.0076	9.09 KB	4.24
Method_FakeItEasy	6,478.5 ns	31.91 ns	28.29 ns	8.81	0.07	0.4883	0.0153	8.05 KB	3.76
Method_Imposter	588.0 ns	2.47 ns	1.93 ns	0.80	0.01	0.2537	0.0029	4.15 KB	1.94
Method_TUnitMocks	2,714.4 ns	15.36 ns	14.37 ns	3.69	0.03	0.4005	0.0076	6.55 KB	3.06

Details

BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.4 LTS (Noble Numbat)

AMD EPYC 7763 2.61GHz, 1 CPU, 4 logical and 2 physical cores

.NET SDK 10.0.201

[Host] : .NET 10.0.5 (10.0.5, 10.0.526.15411), X64 RyuJIT x86-64-v3
Job=InProcess  Toolchain=InProcessEmitToolchain  IterationCount=15

LaunchCount=1  WarmupCount=10

Method	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Allocated	Alloc Ratio
Property_Mockolate	624.6 ns	3.86 ns	3.42 ns	1.00	0.01	0.1116	-	1.83 KB	1.00
Property_Moq	4,967.3 ns	55.21 ns	51.64 ns	7.95	0.09	0.3281	-	5.48 KB	3.00
Property_NSubstitute	5,292.7 ns	27.65 ns	24.51 ns	8.47	0.06	0.5188	0.0076	8.58 KB	4.69
Property_FakeItEasy	4,728.1 ns	62.59 ns	58.54 ns	7.57	0.10	0.3815	0.0153	6.35 KB	3.47
Property_Imposter	389.9 ns	11.53 ns	10.78 ns	0.62	0.02	0.1783	0.0019	2.91 KB	1.59
Property_TUnitMocks	1,964.6 ns	13.55 ns	11.32 ns	3.15	0.02	0.3319	0.0076	5.47 KB	2.99

Details

BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.4 LTS (Noble Numbat)

AMD EPYC 7763 2.61GHz, 1 CPU, 4 logical and 2 physical cores

.NET SDK 10.0.201

[Host] : .NET 10.0.5 (10.0.5, 10.0.526.15411), X64 RyuJIT x86-64-v3
Job=InProcess  Toolchain=InProcessEmitToolchain  IterationCount=15

LaunchCount=1  WarmupCount=10

Method	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Allocated	Alloc Ratio
Event_Mockolate	427.9 ns	2.29 ns	1.91 ns	1.00	0.01	0.0710	-	1.16 KB	1.00
Event_Moq	13,030.3 ns	23.61 ns	20.93 ns	30.45	0.14	0.5951	-	9.76 KB	8.38
Event_NSubstitute	5,498.7 ns	73.38 ns	68.64 ns	12.85	0.16	0.5188	0.0076	8.52 KB	7.32
Event_FakeItEasy	196,123.2 ns	1,069.45 ns	948.04 ns	458.32	2.91	0.4883	0.2441	10.23 KB	8.79
Event_Imposter	1,002.8 ns	17.65 ns	16.51 ns	2.34	0.04	0.5093	0.0134	8.34 KB	7.16
Event_TUnitMocks	2,550.3 ns	160.19 ns	149.84 ns	5.96	0.34	0.2785	0.0057	4.55 KB	3.91

Details

BenchmarkDotNet v0.15.8, Linux Ubuntu 24.04.4 LTS (Noble Numbat)

AMD EPYC 7763 2.61GHz, 1 CPU, 4 logical and 2 physical cores

.NET SDK 10.0.201

[Host] : .NET 10.0.5 (10.0.5, 10.0.526.15411), X64 RyuJIT x86-64-v3
Job=InProcess  Toolchain=InProcessEmitToolchain  IterationCount=15

LaunchCount=1  WarmupCount=10

Method	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Allocated	Alloc Ratio
Callback_Mockolate	437.9 ns	4.65 ns	4.13 ns	1.00	0.01	0.1073	-	1.76 KB	1.00
Callback_Moq	98,090.4 ns	408.68 ns	362.28 ns	224.02	2.19	0.4883	0.2441	8.88 KB	5.05
Callback_NSubstitute	4,414.5 ns	21.17 ns	19.80 ns	10.08	0.10	0.4730	0.0076	7.74 KB	4.40
Callback_FakeItEasy	4,905.0 ns	111.12 ns	103.94 ns	11.20	0.25	0.4120	0.0153	6.81 KB	3.87
Callback_Imposter	412.9 ns	12.13 ns	11.35 ns	0.94	0.03	0.1454	0.0010	2.38 KB	1.36
Callback_TUnitMocks	2,410.1 ns	66.21 ns	61.93 ns	5.50	0.15	0.3777	0.0076	6.18 KB	3.52

[github-actions]

Test Results

    21 files  ±0      21 suites  ±0   5m 44s ⏱️ +54s
 2 886 tests ±0   2 885 ✅ ±0  1 💤 ±0  0 ❌ ±0 
19 393 runs  ±0  19 392 ✅ ±0  1 💤 ±0  0 ❌ ±0 

Results for commit 520f4b2. ± Comparison against base commit 8d8a527.

♻️ This comment has been updated with latest results.

[Copilot]

Pull request overview

This PR reduces runtime allocations in Mockolate’s property and indexer access paths by removing LINQ/predicate usage and inlining property setup resolution logic into the interaction handlers.

Changes:

• Replaced indexer setup lookup via FirstOrDefault(predicate) with an allocation-free loop-based matcher.
• Inlined property setup retrieval/initialization logic into GetProperty/SetProperty to avoid delegate-related allocations.
• Removed now-unused helper methods/usings related to the previous setup lookup approach.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
Source/Mockolate/Setup/MockSetups.cs	Updates indexer setup lookup to a non-LINQ, interaction-based matcher.
Source/Mockolate/MockRegistry.Setup.cs	Removes property/indexer helper methods and an unused using after inlining.
Source/Mockolate/MockRegistry.Interactions.cs	Inlines property setup resolution and updates indexer setup lookup call sites.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

This is addressed in release v2.1.1.