lvDiff.vi causes LabVIEW to crash

[theSloopJohnB]

See this PR for an example.

LabVIEW-DCAF/TagEditorCore#356

Looks like some kind of copy operation fails. From the build log:

"""
[Pipeline] stage
[Pipeline] { (Diff VIs)
[Pipeline] echo
Running LabVIEW diff build between origin/master and this commit
[Pipeline] bat
[W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA] Running batch script

J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA>if exist J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA\diff_dir rd /s /q J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA\diff_dir
[Pipeline] bat
[W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA] Running batch script

J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA>mkdir J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA\diff_dir
[Pipeline] bat
[W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA] Running batch script

J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA>git difftool --no-prompt --extcmd="'L:\labview.bat' $LOCAL $REMOTE diff_dir 2014" origin/master HEAD

J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA>labview-cli --kill --lv-ver 2014 L:\lvDiff.vi -- "C:\Users\Benjamin\AppData\Local\Temp\zRpnsc_Init.vi" "J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA\source\Table API\Listbox\Init.vi" "J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA\diff_dir"
LabVIEW terminated unexpectedly!

J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA>labview-cli --kill --lv-ver 2014 L:\lvDiff.vi -- "C:\Users\Benjamin\AppData\Local\Temp\B5pOO9_Value Change.vi" "J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA\source\Table API\Listbox\Value Change.vi" "J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA\diff_dir"

Error diffing VIs:
VI 1: C:\Users\Benjamin\AppData\Local\Temp\B5pOO9_Value Change.vi
VI 2: J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA\source\Table API\Listbox\Value Change.vi
Results Directory: J:\workspace\W-DCAF_TagEditorCore_PR-356-JET2O2OMPKOOQVIN3KULB5LUCQE7XL4BSN2ZMQCMUCZDN5RCRREA\diff_dir.

Code: 1430
Message:Error 1430 occurred at Copy in lv-cli-steps.lvlib:lvDiff.vi

Possible reason(s):

LabVIEW: The path is empty or relative. You must use an absolute path.

Source: Copy in lv-cli-steps.lvlib:lvDiff.vi ============= Recieved Exit Code 1 Forcing LabVIEW to terminate... """

[theSloopJohnB]

Another thought on this - the diff robot should report when it failed to diff a VI.

Right now, it checks to see if there are any pngs in the output directory and posts them. If it finds none, it posts nothing. Better behavior would be to create a dummy .diff or similar to indicate that it will attempt to diff. That way if labview crashes, the PR still notes that something was attempted to be diffed but failed.