Christoph Thiede uploaded a new version of Kernel to project The Trunk: http://source.squeak.org/trunk/Kernel-jar.1550.mcz
==================== Summary ====================
Name: Kernel-jar.1550 Author: jar Time: 9 January 2024, 8:36:02.1473 pm UUID: f53ab664-7278-8944-8a7c-90660a08f773 Ancestors: Kernel-ct.1549
fix and rename private method #stepToCalleeOrNil to #stepToSenderOrNil
if you debug and do step through to ^2 and then step over in [^2] ensure: [] the debugger incorrectly stops at #resume:through:.
The reason is #resume:through: sends a block as an argument and #stepToCalleeOrNil is just not right for this situation: the purpose of the #stepToSenderOrNil method is to remove the top context from the stack by stepping until the context returns. This means we're not interested in detecting stack increases provided by #stepToCalleeOrNil.
It is only used as a helper method in runUntilErrorOrReturnFrom:
=============== Diff against Kernel-ct.1549 ===============
Item was changed: ----- Method: Context>>runUntilErrorOrReturnFrom: (in category 'controlling') ----- runUntilErrorOrReturnFrom: aSender "ASSUMES aSender is a sender of self. Execute self's stack until aSender returns or an unhandled exception is raised. Return a pair containing the new top context and a possibly nil exception. The exception is not nil if it was raised before aSender returned and it was not handled. The exception is returned rather than openning the debugger, giving the caller the choice of how to handle it." "Self is run by jumping directly to it (the active process abandons thisContext and executes self). However, before jumping to self we insert an ensure block under aSender that jumps back to thisContext when evaluated. We also insert an exception handler under aSender that jumps back to thisContext when an unhandled exception is raised. In either case, the inserted ensure and exception handler are removed once control jumps back to thisContext."
| error ctxt here topContext | here := thisContext.
"Insert ensure and exception handler contexts under aSender" error := nil. ctxt := aSender insertSender: (Context contextOn: UnhandledError do: [:ex | error ifNil: [ error := ex exception. topContext := thisContext. ex resumeUnchecked: here jump] ifNotNil: [ex pass] ]). ctxt := ctxt insertSender: (Context contextEnsure: [error ifNil: [ topContext := thisContext. here jump] ]). self jump. "Control jumps to self"
"Control resumes here once above ensure block or exception handler is executed" ^ error ifNil: [ "No error was raised, remove ensure context by stepping until popped" + [ctxt isDead or: [topContext isNil]] whileFalse: [topContext := topContext stepToSenderOrNil]. - [ctxt isDead or: [topContext isNil]] whileFalse: [topContext := topContext stepToCalleeOrNil]. {topContext. nil}
] ifNotNil: [ "Error was raised, remove inserted above contexts then return signaler context" aSender terminateTo: ctxt sender. "remove above ensure and handler contexts" {topContext. error} ]!
Item was removed: - ----- Method: Context>>stepToCalleeOrNil (in category 'private') ----- - stepToCalleeOrNil - "Step to callee or sender; step to return and answer nil in case sender cannot be returned to." - - | ctxt | - ctxt := self. - [(ctxt willReturn and: [ctxt sender isNil or: [ctxt sender isDead]]) not and: [(ctxt := ctxt step) == self]] whileTrue. - ctxt == self ifTrue: [^nil]. - ^ctxt!
Item was added: + ----- Method: Context>>stepToSenderOrNil (in category 'private') ----- + stepToSenderOrNil + "Step to sender or step to return and answer nil in case sender cannot be returned to." + + | ctxt | + ctxt := self. + [(ctxt willReturn and: [ctxt sender isNil or: [ctxt sender isDead]]) not and: [(ctxt := ctxt step) == self or: [ctxt hasSender: self]]] whileTrue. + ctxt == self ifTrue: [^nil]. + ^ctxt!