On Mon, Nov 13, 2017 at 9:32 PM, Thomas Dupriez < thomas.dupriez@ens-paris-saclay.fr> wrote:
Le 13/11/2017 à 14:08, Ben Coman a écrit :
On Mon, Nov 13, 2017 at 8:40 PM, Thomas Dupriez <thomas.dupriez@ens-paris- saclay.fr> wrote:
I dug a bit in this issue. Here are the results:
# Problem raised by Stephanne Code like the following is open in the debugger:
`myMethod 1+1. <PROGRAMCOUNTER> MyClass new myEvalBlock: [ 2+2. <CURSOR> ]. 3+3.`
The program counter is on the 1+1, the cursor is at the end of the 2+2 line. Right-click, "Run to here". -> the program counter moves to the 3+3, and does not stop at the 2+2 (where the cursor is). Even though the 2+2 does get evaluated (the myEvalBlock method evaluates the blocks it receives). If there was no code after the block, the debugger would jump back to the caller of myMethod.
# Why this happens The implementation of RunToHere (source code below) is basically to stepOver until the context is different or the source code position of the program counter is higher or equal to the source code position of the cursor/selection.
Since the debugger uses stepOver, it executes myEvalBlock without stopping, reaches the 3+3 and see it has gone further than the source code position of the cursorm so it stops.
Source code of DebugSession>>#runToSelection:inContext:
`runToSelection: selectionInterval inContext: aContext "Attempt to step over instructions in selectedContext until the execution reaches the selected instruction. This happens when the program counter passes the begining of selectionInterval.
A not nill and valid interval is expected."
(self pcRangeForContext: aContext) first >= selectionInterval first ifTrue: [ ^self ]. self stepOver: aContext. [ aContext == self interruptedContext and: [ (self pcRangeForContext: aContext) first < selectionInterval first ] ] whileTrue: [ self stepOver: aContext ]`
# Observations and thoughts - Replacing the stepOver with a stepInto -> This made the RunToHere stops when resolving the 'new' message (because the context changes).
Thanks for looking into this Thomas. What happens if you use stepThrough rather than stepInto?
cheers -ben
Using `stepThrough: aContext` instead of `stepInto: aContext`, the RunToHere in the block stops at the intended place: the 2+2. Printing the sequence of `self pcRangeForContext: aContext` yields the following. It doesn't show precisely the stop in the block, and instead shows an interval encompassing the whole block. That's what I was using to see where the execution was going during the RunToHere loop so I guess that's not a precise enough indicator for this situation... (21 to: 22)(34 to: 36)(49 to: 60)(38 to: 60)(38 to: 60)
I also tried the case where the block does not get evaluated (changing myEvalBlock so that it does nothing). In this situation, the RunToHere with a stepThrough ends up at the intended place, the 3+3.
So... just use stepThrough for the RunToHere I guess?
Seems like expected behaviour. Could you create an Issue/Pull Request to provide some concrete code to review? Now the trick will be if you can devise some tests to go with this. For examples perhaps look at senders of newDebugSessionNamed:startedAt: including SpecDebugger>>testBasic. cheers -ben
Thomas
- Replacing the stepOver with stepInto and removing the equal condition on contexts -> The RunToHere goes to the 3+3. Looking at the source code position of the program counter, it doesn't enter the block and seems to resolve it in a single step. I don't really get why that is, considering using the stepInto button of the debugger does enter the block. Here is the series of source code positions of the program counter during the RunToHere: (21 to: 22)(34 to: 36)(34 to: 36)(49 to: 60)(38 to: 60)(38 to: 60)(65 to: 66). However, removing the equal condition on contexts means that if the method call returns before reaching the cursor, it won't stop!
- An idea could be to have the RunToHere place a metalink on the selected node and let the execution run until it hits the metalink, which then updates the debugger. Potential problems are that it implies installing a metalink on a method that is already on the stack, which may not be that easy to do properly (in particular, it affects the program counter since it changes the bytecode), and there is the potential case where the metalink is never reached (for example imagine the myEvalBlock: method of my example is just storing the block and not evaluating it).
Cheers, Thomas
Le 09/11/2017 à 22:06, Stephane Ducasse a écrit :
Agreed. Thomas? It would be a good bone to ... (Un bon os a ronger) .
Stef
On Thu, Nov 9, 2017 at 4:32 AM, Tudor Girba <tudor@tudorgirba.com> wrote:
Hi,
The basic tools, such as debugger, are expected to work. If something does not work, itâs a bug.
Cheers, Doru
On Nov 8, 2017, at 11:59 PM, Tim Mackinnon <tim@testit.works>
<tim@testit.works> wrote:
I think it's broken in Pharo 6 too, as I often find it unreliable.
It's hard to know what should work anymore - we really need a stabilisation release to let the dust settle.
I'm always a bit reticent to report things as I'm not sure what you expect to work.
Tim
Sent from my iPhone
On 8 Nov 2017, at 20:40, Stephane Ducasse <stepharo.self@gmail.com>
wrote:
Hi
I have the following method and I have my cursor -MY CURSOR HERE- I select the menu run to here and .... I exit the method. :(
Is run to here working in Pharo 70? I start to get worry about the number of bugs I get when using Pharo70.
Stef
fileOut "File out the receiver, to a file whose name is a function of the change-set name and a unique numeric tag."
| nameToUse | self halt. self class promptForDefaultChangeSetDirectoryIfNecessary. nameToUse := (self defaultChangeSetDirectory / self name , 'cs') nextVersion basename. UIManager default showWaitCursorWhile: [ | internalStream | internalStream := (String new: 10000) writeStream.
-MY CURSOR HERE-
internalStream header; timeStamp. self fileOutPreambleOn: internalStream. self fileOutOn: internalStream. self fileOutPostscriptOn: internalStream. CodeExporter writeSourceCodeFrom: internalStream baseName: (nameToUse copyFrom: 1 to: nameToUse size - 3) isSt: false ]
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