56 lines
1.7 KiB
ReStructuredText
56 lines
1.7 KiB
ReStructuredText
.. title:: clang-tidy - bugprone-switch-missing-default-case
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bugprone-switch-missing-default-case
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====================================
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Ensures that switch statements without default cases are flagged, focuses only
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on covering cases with non-enums where the compiler may not issue warnings.
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Switch statements without a default case can lead to unexpected
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behavior and incomplete handling of all possible cases. When a switch statement
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lacks a default case, if a value is encountered that does not match any of the
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specified cases, the program will continue execution without any defined
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behavior or handling.
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This check helps identify switch statements that are missing a default case,
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allowing developers to ensure that all possible cases are handled properly.
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Adding a default case allows for graceful handling of unexpected or unmatched
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values, reducing the risk of program errors and unexpected behavior.
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Example:
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.. code-block:: c++
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// Example 1:
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// warning: switching on non-enum value without default case may not cover all cases
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switch (i) {
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case 0:
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break;
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}
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// Example 2:
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enum E { eE1 };
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E e = eE1;
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switch (e) { // no-warning
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case eE1:
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break;
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}
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// Example 3:
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int i = 0;
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switch (i) { // no-warning
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case 0:
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break;
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default:
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break;
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}
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.. note::
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Enum types are already covered by compiler warnings (comes under -Wswitch)
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when a switch statement does not handle all enum values. This check focuses
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on non-enum types where the compiler warnings may not be present.
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.. seealso::
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The `CppCoreGuideline ES.79 <https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#Res-default>`_
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provide guidelines on switch statements, including the recommendation to
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always provide a default case.
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