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  1. Rules Repository
  2. RSPEC-1862 Related "if/else if" statements should not have the same condition
  3. RSPEC-4934

Scala: Related "if"/"else if" statements and "case" in a "match" should not have the same condition

    Details

    • Type: Language-Specification
    • Status: Active
    • Resolution: Unresolved
    • Labels:
      None
    • Impact:
      Unknown 'null' severity
    • Likelihood:
      Unknown 'null' severity

      Description

      A match and a chain of if/else if statements is evaluated from top to bottom. At most, only one branch will be executed: the first one with a condition that evaluates to true.

      Therefore, duplicating a condition automatically leads to dead code. Usually, this is due to a copy/paste error. At best, it's simply dead code and at worst, it's a bug that is likely to induce further bugs as the code is maintained, and obviously it could lead to unexpected behavior.

      For a match, the second case will never be executed, rendering it dead code. Worse there is the risk in this situation that future maintenance will be done on the dead case, rather than on the one that's actually used.

      Noncompliant Code Example

      if (param == 1) {
        openWindow
      } else if (param == 2) {
        closeWindow
      } else if (param == 1) { // Noncompliant
        moveWindowToTheBackground
      }
      
      param match {
        case 1 =>
        // ...
        case 3 =>
        // ...
        case 1 => // Noncompliant
        // ...
        case _ =>
        //...
      }
      

      Compliant Solution

      if (param == 1) {
        openWindow
      } else if (param == 2) {
        closeWindow
      } else if (param == 3) {
        moveWindowToTheBackground
      }
      
      param match {
        case 1 =>
        // ...
        case 3 =>
        // ...
        case _ =>
        //...
      }
      

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            • Assignee:
              Unassigned
              Reporter:
              alban.auzeill Alban Auzeill
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              Dates

              • Created:
                Updated: