Complex Methods should be 100% tested

Rule ND1610 Code Coverage

Detects methods with a low maintainability index and insufficient test coverage: hard to understand, error prone and risky to modify. Maintainability index definition: https://www.ndepend.com/docs/code-metrics#MaintainabilityIndex

How to fix

1. Break large or complex methods into smaller, focused units.

2. Improve readability: clear naming, consistent formatting, less nesting.

3. Write unit tests validating both common and edge cases.

4. Ensure refactored code is fully covered by tests before merging.

CQLinq source

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// <Name>Complex Methods should be 100% tested</Name>
// <Id>ND1610:ComplexMethodsShouldBeFullyTested</Id>

warnif count > 0 
from m in JustMyCode.Methods
where m.NbLinesOfCode >= 30 && m.MaintainabilityIndex <= 40 &&
      m.CoverageDataAvailable && m.PercentageCoverage < 100 &&
      m.CyclomaticComplexity != null && m.CyclomaticComplexity >= 10
orderby m.MaintainabilityIndex ascending
select new { 
   m, 
   m.MaintainabilityIndex,
   m.CyclomaticComplexity, 
   m.NbLinesOfCode,
   m.PercentageCoverage,
   Debt = 
    (((60 - m.MaintainabilityIndex)/25f)*(100 - m.PercentageCoverage))
    .Linear(10, 6,  150, 120).ToMinutes().ToDebt(),
   Severity = Severity.High
}

//<Expl>
// The *{0}* has a low maintainability index *{1}* and is highly complex.  
// Current test coverage is only *{4}%*.  
// Refactor the code and add sufficient tests to ensure full coverage 
// and improved maintainability.
//</Expl>

//<Desc>
// Detects methods with a low maintainability index and insufficient test
// coverage: hard to understand, error prone and risky to modify.
// Maintainability index definition:
// https://www.ndepend.com/docs/code-metrics#MaintainabilityIndex
//</Desc>

//<HowToFix>
// 1. Break large or complex methods into smaller, focused units.
//
// 2. Improve readability: clear naming, consistent formatting, less nesting.
//
// 3. Write unit tests validating both common and edge cases.
//
// 4. Ensure refactored code is fully covered by tests before merging.
//</HowToFix>

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