Contributing Advent 17: Printing stacks
Anybody who is vaguely familiar with Xdebug probably has seen its glorious orange stack traces gracing their screens. In case you have not, they look like:
In this case, the tell_a_lie_and_hurt_you() function tried to call strlen() with incorrect arguments.
Xdebug overloads PHP's internal error handler to do this, but it is also possible to trigger stack traces yourself. You can of course use trigger_error(), but Xdebug also provides the xdebug_print_function_stack() function. Running xdebug_print_function_stack() instead of the erroneous strlen() results in:
As the documentation state, you can also provide your own message:
<?php
function tell_a_lie_and_hurt_you()
{
xdebug_print_function_stack("You have been rickrolled!");
}
Which then results in:
This was all good, and then my friend Rob asked:
hypothetically, how hard would it be to change xdebug_print_function_stack() so that it didn't output the filename and line number in the orange box?
Well, it didn't turn out to be very hard. Rob requested this feature because he was writing his own error handler. And with your own error handler it does not make a whole lot of sense to show where xdebug_print_function_stack() was called from. After my commit, you can now supply a second argument to xdebug_print_function_stack():
<?php
function tell_a_lie_and_hurt_you()
{
xdebug_print_function_stack("You have been rickrolled!", XDEBUG_STACK_NO_DESC);
}
Which then results in a stack trace without header:
This new feature will be part of Xdebug 2.3.
Life Line
Created a vending_machine
Updated a bus_stop
I hiked 5.4km in 2h35m46s
I walked 2.2km in 27m13s
I walked 1.6km in 32m29s
I walked 3.3km in 34m33s
Updated a confectionery shop, a massage shop, and 2 other objects; Deleted a books shop
I hiked 7.0km in 4h21m00s
Updated a deli shop and a pet_grooming shop
I walked 4.2km in 49m42s
I walked 1.4km in 10m14s
I walked 2.2km in 1h43m13s
I walked 4.4km in 1h25m00s
Updated a cafe
Updated a bar
I walked 1.7km in 19m07s
I got a new lens. It's a little bit larger, and loads heavier, than my older one.
I walked 1.6km in 15m10s
Updated a pub
I walked 4.5km in 41m34s
Merge branch 'v2022'
Merge branch 'isspace-fixes' into v2022
Cast to 'unsigned char' for all ctype style functions (isspace, toupp…
I saw a Kingfisher fishing yesterday!
It's not a great photo, but it was great seeing it using the branch as a perch for fishing.




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