Good suggestions from Eric. Another is that you can "drop some breadcrumbs", i.e. place a "seen" node metadata marker and skip the next time around. This falls into the category of a workaround rather than a fix for your expectation, but we do legitimately walk the tree multiple times in a few places. We make sure our transforms are idempotent in that case. It doesn't mean there might not be a bug somewhere and we walk more than needed for some edge case. Perhaps you could expand your example and we can check further.
Cheers, Paul. On Mon, Apr 3, 2023 at 11:23 PM Milles, Eric (TR Technology) via dev < dev@groovy.apache.org> wrote: > You can try visiting at an earlier compile phase (maybe before instruction > selection) to see the AST before some SC transforms are applied. > Otherwise, I have used the source location as a key to understand if > something is coming in again. Often generated methods will include some of > the source elements again. > > > > Here is an example of an AST visitor that deals with a number of the > idiosyncrasies of the tree. > https://github.com/groovy/groovy-eclipse/blob/master/base/org.eclipse.jdt.groovy.core/src/org/eclipse/jdt/groovy/core/util/DepthFirstVisitor.java > > > > *From:* Saravanan Palanichamy <chava...@gmail.com> > *Sent:* Saturday, April 1, 2023 1:35 AM > *To:* dev@groovy.apache.org > *Subject:* [EXT] Duplicate visits to expressions defined in RHS of a > setter > > > > *External Email:* Use caution with links and attachments. > > > > Hello Groovy Devs > > - I have a class defined MyTestClass in java/kotlin (does not matter) > - I have a groovy class defined MyClassDefinedInGroovy > - I have code in a groovy function that is creating these classes and > setting a variable in the object. I compile this with static compilation > turned on > - I visit this class using a simple visitor that prints all constants > visited (I have attached both code and groovy file in this email) > > For the class defined in java > > - In 3.0.16, all constants are visited twice. This is not what I would > expect but at least it is consistent > - In 3.0.5, the setters with a property based LHS are visited twice, > but those with a variable based LHS, only one visit as expected > > For the class defined in Groovy, In both 3.0.5 and 3.0.16, all constants > are visited only once. This is what I would expect > > > > Multiple visits to the same code is causing an issue for me because I > collect metadata about the code for use elsewhere and I end up getting > duplicates that cannot be cleanly ignored (because its not just variables, > its anything on the RHS, closures, method calls, etc) > > > > I debugged this a bit and found out that for classes imported from Java, > the compiler seems to be using PoppingMethodCallExpression and > PoppingListOfExpressionsExpression. The latter has code that initializes > the parent with two expressions, the tmp variable and the method call. The > method call also includes the tmp variable which I think is causing this > duplicate visit. > > > > public PoppingListOfExpressionsExpression(final TemporaryVariableExpression > tmp, final PoppingMethodCallExpression call) { > > // This array initialization with tmp and call is a problem because call > also holds tmp and visits it > > super(Arrays.asList(tmp, call)); > this.tmp = tmp; > this.call = call; > } > > > > What are my options if I dont want to handle the duplicate visit? This > problem exists in some scenarios in 3.0.5 and is consistently a problem in > 3.0.16 > > > > regards > > Saravanan >
