document and work around range retracing limitation for accessing for…

…ked contexts #90
hpi-swa-lab · Jul 24, 2022 · 174b96a · 174b96a
1 parent 2a06144
commit 174b96a
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Showing 4 changed files with 15 additions and 7 deletions.
diff --git a/packages/TraceDebugger.package/TDBCursor.class/class/rangeRetracingForkAccess.st b/packages/TraceDebugger.package/TDBCursor.class/class/rangeRetracingForkAccess.st
@@ -0,0 +1,4 @@
+documentation
+rangeRetracingForkAccess
+
+	"Currently, access from the simulated code to stored context instances from its stack might fail when the execution has been forked before. A prominent example of this limitation are non-local returns within an unwind context (#aboutToReturn:through:). See https://github.com/hpi-swa-lab/squeak-tracedebugger/issues/90."
diff --git a/packages/TraceDebugger.package/TDBCursor.class/methodProperties.json b/packages/TraceDebugger.package/TDBCursor.class/methodProperties.json
@@ -9,6 +9,7 @@
 		"moveUpstream" : "ct 3/11/2022 20:15",
 		"on:" : "ct 11/20/2021 21:25",
 		"proxyHacks" : "ct 7/3/2022 20:56",
+		"rangeRetracingForkAccess" : "ct 7/24/2022 15:45",
 		"traceClass" : "ct 11/18/2021 18:06",
 		"traceForBlock:" : "ct 5/14/2022 16:26",
 		"traceForContext:" : "ct 5/14/2022 16:14" },

diff --git a/packages/TraceDebugger.package/TDBHistoryExplorer.class/instance/detailsTextForValue..st b/packages/TraceDebugger.package/TDBHistoryExplorer.class/instance/detailsTextForValue..st
@@ -1,10 +1,13 @@
 labels & details
 detailsTextForValue: value
 
-	[value isText ifTrue: [^ self detailsTextForTextValue: value].
-	value isForm ifTrue: [^ self detailsTextForFormValue: value].
-	value isMorph ifTrue: [^ self detailsTextForMorphValue: value].
+	self flag: #rangeRetracingForkAccess. "We would want to use non-local returns here which would send #aboutToReturn:through: which is currently not supported during range retracing."
 
-	^ self detailsTextForObjectValue: value]
-		on: self commonErrors do: [:ex |
-			^ self errorText: 'display error' exception: ex]
+	^ [true
+		caseOf:
+			{[value isText] -> [self detailsTextForTextValue: value].
+			[value isForm] -> [self detailsTextForFormValue: value].
+			[value isMorph] -> [self detailsTextForMorphValue: value]}
+		otherwise: [self detailsTextForObjectValue: value]]
+			on: self commonErrors do: [:ex |
+				self errorText: 'display error' exception: ex]
diff --git a/packages/TraceDebugger.package/TDBHistoryExplorer.class/methodProperties.json b/packages/TraceDebugger.package/TDBHistoryExplorer.class/methodProperties.json
@@ -64,7 +64,7 @@
 		"detailsTextForObjectValue:" : "ct 7/21/2022 21:17",
 		"detailsTextForResult:fromRoot:" : "ct 7/22/2022 20:57",
 		"detailsTextForTextValue:" : "ct 7/22/2022 00:25",
-		"detailsTextForValue:" : "ct 7/22/2022 13:30",
+		"detailsTextForValue:" : "ct 7/24/2022 15:46",
 		"doItContext" : "ct 6/18/2022 23:34",
 		"doItReceiver" : "ct 6/18/2022 23:34",
 		"errorLabelFor:" : "ct 7/3/2022 23:48",