Check stickiness prior processing dependent unload

Move stickiness check when unloading a module prior processing any
automated module handling mechanism.

Stickiness check procedure is renamed failOrSkipUnloadIfSticky and moved
from interp.tcl to modeval.tcl file.

Fixes #536

NEWS.rst

@@ -188,6 +188,8 @@ Modules 5.5.0 (not yet released)
   when trying to reload Dependent Reload modules that conflict with other
   loaded modules. This error may be by-passed with :option:`--force`
   command-line option.
+* Move stickiness check when unloading a module prior processing any automated
+  module handling mechanism. (fix issue #536)
 
 .. warning:: Variant names are now fully checked instead of just verifying
    their first character. Only characters within the ``A-Za-z0-9_-`` range are

tcl/interp.tcl.in

@@ -184,50 +184,6 @@ x-resource     {x-resource     x-resource     reportCmd      nop            nop
    }
 }
 
-# Fail unload attempt if module is sticky, unless if forced or reloading
-# Also fail unload if mod is super-sticky even if forced, unless reloading
-proc skipUnloadIfSticky {mode modname modfile} {
-   if {$mode ne {unload}} {
-      return 0
-   }
-
-   # when loaded, tags applies to mod name and version (not with variant)
-   set is_supersticky_not_reloading [expr {[isModuleTagged $modname\
-      super-sticky 1 $modfile] && [currentState reloading_supersticky] ne\
-      $modname}]
-   set is_sticky_not_reloading [expr {[isModuleTagged $modname sticky 1\
-      $modfile] && [currentState reloading_sticky] ne $modname &&\
-      [currentState unloading_sticky] ne $modname}]
-   set sticky_purge [expr {[getState commandname] eq {purge} ? [getConf\
-      sticky_purge] : {}}]
-
-   if {!$is_supersticky_not_reloading && $is_sticky_not_reloading &&\
-      [getState force]} {
-      reportWarning [getStickyForcedUnloadMsg]
-   } elseif {$is_supersticky_not_reloading || $is_sticky_not_reloading} {
-      # restore changed states prior raising error
-      lpopState debug_msg_prefix
-      lpopState modulepath
-      lpopState specifiedname
-      lpopState modulename
-      lpopState modulenamevr
-      lpopState modulefile
-
-      set msg [getStickyUnloadMsg [expr {$is_supersticky_not_reloading ?\
-         {super-sticky} : {sticky}}]]
-      # no message if sticky_purge is set to silent
-      switch -- $sticky_purge {
-         error - {} {knerror $msg}
-         warning {reportWarning $msg}
-      }
-
-      # skip unload without raised error
-      return 1
-   }
-
-   return 0
-}
-
 proc execute-modulefile {modfile modname modnamevrvar modspec requested\
    {up_namevr 1} {fetch_tags 1} {modpath {}}} {
    # link to modnamevr variable name from calling ctx if content update asked
@@ -267,12 +223,6 @@ proc execute-modulefile {modfile modname modnamevrvar modspec requested\
       set nearlyforbidwarn 1
    }
 
-   # fail unload when sticky
-   if {[skipUnloadIfSticky $mode $modname $modfile]} {
-      # skip end of unload upper level process when no error raised
-      return -code continue 0
-   }
-
    if {![info exists ::g_modfileUntrackVars]} {
       # list variable that should not be tracked for saving
       array set ::g_modfileUntrackVars [list ModulesCurrentModulefile 1 env 1]

tcl/modeval.tcl

@@ -1138,6 +1138,38 @@ proc reloadDepReModules {} {
    reloadModuleListLoadPhase $depre_list $err_msg_tpl depre
 }
 
+# Fail unload attempt if module is sticky, unless if forced or reloading
+# Also fail unload if mod is super-sticky even if forced, unless reloading
+proc failOrSkipUnloadIfSticky {modname modfile} {
+   # when loaded, tags applies to mod name and version (not with variant)
+   set is_supersticky_not_reloading [expr {[isModuleTagged $modname\
+      super-sticky 1 $modfile] && [currentState reloading_supersticky] ne\
+      $modname}]
+   set is_sticky_not_reloading [expr {[isModuleTagged $modname sticky 1\
+      $modfile] && [currentState reloading_sticky] ne $modname &&\
+      [currentState unloading_sticky] ne $modname}]
+   set sticky_purge [expr {[getState commandname] eq {purge} ? [getConf\
+      sticky_purge] : {}}]
+
+   if {!$is_supersticky_not_reloading && $is_sticky_not_reloading &&\
+      [getState force]} {
+      reportWarning [getStickyForcedUnloadMsg]
+   } elseif {$is_supersticky_not_reloading || $is_sticky_not_reloading} {
+      set msg [getStickyUnloadMsg [expr {$is_supersticky_not_reloading ?\
+         {super-sticky} : {sticky}}]]
+      # no message if sticky_purge is set to silent
+      switch -- $sticky_purge {
+         error - {} {knerror $msg}
+         warning {reportWarning $msg}
+      }
+
+      # skip unload without raising error
+      return 1
+   }
+
+   return 0
+}
+
 # ;;; Local Variables: ***
 # ;;; mode:tcl ***
 # ;;; End: ***

tcl/subcmd.tcl.in

@@ -1546,6 +1546,10 @@ proc cmdModuleUnload {context match auto force onlyureq args} {
 
       pushSettings
       if {[set errCode [catch {
+         if {[failOrSkipUnloadIfSticky $modname $modfile]} {
+            continue
+         }
+
          # stop unless forced or auto handling mode enabled if unloading
          # module violates a registered prereq
          set prereq_list [getDependentLoadedModuleList [list $modname]]