Coding standards: Add guideline for variable scope in if statements#346
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nyalldawson wants to merge 2 commits intomasterfrom
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Coding standards: Add guideline for variable scope in if statements#346nyalldawson wants to merge 2 commits intomasterfrom
nyalldawson wants to merge 2 commits intomasterfrom
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troopa81
reviewed
Aug 26, 2025
troopa81
reviewed
Aug 26, 2025
Co-authored-by: Julien Cabieces <julien.cabieces@oslandia.com>
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Thanks @troopa81 ! |
uclaros
reviewed
Aug 28, 2025
| c++17 [if statement with initializer](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0305r0.html) form can be used to limit the scope: | ||
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| ``` cpp | ||
| if ( QgsMarkerSymbol *marker = renderer->symbol; marker->symbolLayerCount() > 1 ) |
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Better add the pointer checking to this example too:
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| if ( QgsMarkerSymbol *marker = renderer->symbol; marker->symbolLayerCount() > 1 ) | |
| if ( QgsMarkerSymbol *marker = renderer->symbol; marker && marker->symbolLayerCount() > 1 ) |
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After encountering a real bug because of this (qgis/QGIS#64871), I would suggest we also add a rule to always check the pointer initialized within the if initializer.
I couldn't find a related check in clang-tidy, however we could craft something with regular expressions.
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Adds a coding guideline to limit the leakage of variables used for
ifstatements by initializing them within theifstatement scope