2c01ea7ff2
* Add variable for ruleguard config directory * Add variable for ruleguard config directory * Add variable for ruleguard config directory * Add variable for ruleguard config directory * Add unit tests * Add unit tests for ruleguard * Add unit tests for ruleguard * Add unit tests for ruleguard * Add unit tests for ruleguard, fix package name
23 lines
728 B
Go
23 lines
728 B
Go
// go:build ruleguard
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package ruleguard
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import "github.com/quasilyte/go-ruleguard/dsl"
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// Suppose that we want to report the duplicated left and right operands of binary operations.
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//
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// But if the operand has some side effects, this rule can cause false positives:
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// `f() && f()` can make sense (although it's not the best piece of code).
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//
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// This is where *filters* come to the rescue.
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func DupSubExpr(m dsl.Matcher) {
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// All filters are written as a Where() argument.
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// In our case, we need to assert that $x is "pure".
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// It can be achieved by checking the m["x"] member Pure field.
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m.Match(`$x || $x`,
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`$x && $x`,
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`$x | $x`,
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`$x & $x`).
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Where(m["x"].Pure).
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Report(`suspicious identical LHS and RHS`)
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}
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