Hold module not found error message when report is held

Update held report mechanism when loading requirement to also hold error
messages occurring outside of sub evaluation. Module not found error
message is now held and dropped if an alternative requirement module is
found and loaded afterward.

Fixes #511.

NEWS.rst

@@ -59,10 +59,13 @@ Modules 5.4.0 (not yet released)
 * Update requirement load error report to place it only under the message
   block of the module requiring this load. This change helps to better
   understand the chronology of actions and from where an error occurs.
-* Do not report requirement load error when an an alternative requirement
-  module is found and loaded afterward. (fix issue #509)
+* Do not report requirement load error when an alternative requirement module
+  is found and loaded afterward. (fix issue #509)
 * Do not render an error exit code on multi-module option requirement when
   one module option fails to load but another does. (fix issue #510)
+* Do not report *module not found* error when loading a requirement if an
+  alternative requirement module is found and loaded afterward. (fix issue
+  #511)
 
 
 .. _5.3 release notes:

tcl/modeval.tcl

@@ -656,7 +656,10 @@ proc loadRequirementModuleList {tryload optional tag_list args} {
       for {set i 0} {$i<$imax && $prereqloaded==0} {incr i 1} {
          set arg [lindex $args $i]
 
-         # hold output of each evaluation until they are all done to drop
+         # hold output from current evaluation to catch 'module not found'
+         # message that occurs outside of sub evaluation
+         lappendState reportholdrecid [currentState msgrecordid]
+         # hold output of each sub evaluation until they are all done to drop
          # those that failed if one succeed or if optional
          set curholdid load-$i-$arg
          lappendState reportholdid $curholdid
@@ -665,6 +668,7 @@ proc loadRequirementModuleList {tryload optional tag_list args} {
             # if an error is raised, release output and rethrow the error
             # (could be raised if no modulepath defined for instance)
             lpopState reportholdid
+            lpopState reportholdrecid
             lappend holdidlist $curholdid report
             releaseHeldReport {*}$holdidlist
             knerror $errorMsg
@@ -674,6 +678,7 @@ proc loadRequirementModuleList {tryload optional tag_list args} {
             set ret $retlo
          }
          lpopState reportholdid
+         lpopState reportholdrecid
 
          if {[is-loaded $arg]} {
             set prereqloaded 1

tcl/report.tcl.in

@@ -285,8 +285,15 @@ proc __reportSeparateNextContent {} {
 
 # save message for block rendering
 proc recordMessage {message {recordtop 0}} {
-   lappend ::g_msgRecord([expr {$recordtop ? [topState msgrecordid] :\
-      [currentState msgrecordid]}]) $message
+   set recid [expr {$recordtop ? [topState msgrecordid] : [currentState\
+      msgrecordid]}]
+
+   if {$recid eq [currentState reportholdrecid]} {
+      lappend ::g_holdReport([currentState reportholdid]) [list\
+         recordMessage $message $recordtop]
+   } else {
+      lappend ::g_msgRecord($recid) $message
+   }
 }
 
 # check if some msg have been recorded for current evaluation