Curly braces can be omitted from a one-line block, such as with an if
statement or for
loop, but doing so can be
misleading and induce bugs.
This rule raises an issue when the whitespacing of the lines after a one line block indicates an intent to include those lines in the block, but the omission of curly braces means the lines will be unconditionally executed once.
Note that this rule considers tab characters to be equivalent to 1 space. If you mix spaces and tabs you will sometimes see issues in code which look fine in your editor but are confusing when you change the size of tabs.
if (condition) firstActionInBlock(); secondAction(); // Noncompliant; executed unconditionally thirdAction(); if (condition) firstActionInBlock(); secondAction(); // Noncompliant; secondAction executed unconditionally if (condition) firstActionInBlock(); // Noncompliant secondAction(); // Executed unconditionally if (condition); secondAction(); // Noncompliant; secondAction executed unconditionally String str = null; for (int i = 0; i < array.length; i++) str = array[i]; doTheThing(str); // Noncompliant; executed only on last array element
if (condition) { firstActionInBlock(); secondAction(); } thirdAction(); String str = null; for (int i = 0; i < array.length; i++) { str = array[i]; doTheThing(str); }