improve problem solution if a requirement cannot be fulfilled. Bug #358560

diff --git a/zypp/sat/SATResolver.cc b/zypp/sat/SATResolver.cc
index fc614a5..8cade01 100644 (file)
--- a/zypp/sat/SATResolver.cc
+++ b/zypp/sat/SATResolver.cc
@@ -18,7 +18,7 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  * 02111-1307, USA.
  */
-
+#include <sstream>
 #include "zypp/solver/detail/Helper.h"
 #include "zypp/base/String.h"
 #include "zypp/Capability.h"
@@ -33,6 +33,7 @@
 #include "zypp/CapFilters.h"
 #include "zypp/sat/SATResolver.h"
 #include "zypp/sat/Pool.h"
+#include "zypp/sat/WhatProvides.h"
 #include "zypp/solver/detail/ProblemSolutionCombi.h"
 
 extern "C" {
@@ -69,6 +70,35 @@ int vendorCheck (Pool *pool, Solvable *solvable1, Solvable *solvable2) {
     return VendorAttr::instance().equivalent(id2str(pool, solvable1->vendor), id2str(pool, solvable2->vendor)) ? 0:1;
 }
 
+
+string
+itemToString (PoolItem item, bool shortVersion)
+{
+    ostringstream os;
+    if (!item) return "";
+
+    if (item->kind() != ResTraits<zypp::Package>::kind)
+       os << item->kind() << ':';
+    os  << item->name();
+    if (!shortVersion) {
+       os << '-' << item->edition();
+       if (item->arch() != "") {
+           os << '.' << item->arch();
+       }
+       Repository s = item->repository();
+       if (s) {
+           string alias = s.info().alias();
+           if (!alias.empty()
+               && alias != "@system")
+           {
+               os << '[' << s.info().alias() << ']';
+           }
+       }
+    }
+    return os.str();
+}
+       
+
 //---------------------------------------------------------------------------
 
 std::ostream &
@@ -506,7 +536,7 @@ struct FindPackage : public resfilter::ResObjectFilterFunctor
 };
 
 
-std::string SATResolver::SATprobleminfoString(Id problem)
+string SATResolver::SATprobleminfoString(Id problem, string &detail)
 {
   string ret;
   Pool *pool = _solv->pool;
@@ -552,7 +582,55 @@ std::string SATResolver::SATprobleminfoString(Id problem)
          break;
       case SOLVER_PROBLEM_DEP_PROVIDERS_NOT_INSTALLABLE:
          s = pool_id2solvable(pool, source);
-         ret = str::form (_("%s requires %s, but none of the providers can be installed"), solvable2str(pool, s), dep2str(pool, dep));
+         Capability cap(dep);
+         sat::WhatProvides possibleProviders(cap);
+
+         // check, if a provider will be deleted
+         typedef list<PoolItem> ProviderList;
+         ProviderList providerlistInstalled, providerlistUninstalled;
+         for_( iter1, possibleProviders.begin(), possibleProviders.end() ) {
+             PoolItem provider1 = ResPool::instance().find( *iter1 );
+             // find pair of an installed/uninstalled item with the same NVR
+             bool found = false;
+             for_( iter2, possibleProviders.begin(), possibleProviders.end() ) {
+                 PoolItem provider2 = ResPool::instance().find( *iter2 );                
+                 if (compareByNVR (provider1.resolvable(),provider2.resolvable()) == 0
+                     && (provider1.status().isInstalled() && provider2.status().isUninstalled() 
+                         || provider2.status().isInstalled() && provider1.status().isUninstalled()))  {
+                     found = true;
+                     break;
+                 }
+             }
+             if (!found) {
+                 if (provider1.status().isInstalled())
+                     providerlistInstalled.push_back(provider1);
+                 else
+                     providerlistUninstalled.push_back(provider1);
+             }
+         }
+
+         ret = str::form (_("%s requires %s, but this requirement cannot be provided"), solvable2str(pool, s), dep2str(pool, dep));
+         if (providerlistInstalled.size() > 0) {
+             detail += _("deleted providers: ");
+             for (ProviderList::const_iterator iter = providerlistInstalled.begin(); iter != providerlistInstalled.end(); iter++) {
+                 if (iter == providerlistInstalled.begin())
+                     detail += itemToString (*iter, false);
+                 else
+                     detail += "\n                   " + itemToString (*iter, false);
+             }
+         }
+         if (providerlistUninstalled.size() > 0) {
+             if (detail.size() > 0)
+                 detail += _("\nuninstallable providers: ");
+             else
+                 detail = _("uninstallable providers: ");                
+             for (ProviderList::const_iterator iter = providerlistUninstalled.begin(); iter != providerlistUninstalled.end(); iter++) {
+                 if (iter == providerlistUninstalled.begin())
+                     detail += itemToString (*iter, false);                  
+                 else
+                     detail += "\n                   " + itemToString (*iter, false);                
+             }
+         }       
          break;
   }
 
@@ -576,10 +654,11 @@ SATResolver::problems ()
        while ((problem = solver_next_problem(_solv, problem)) != 0) {
            MIL << "Problem " <<  pcnt++ << ":" << endl;
            MIL << "====================================" << endl;
-           string whatString = SATprobleminfoString(problem);
+           string detail;
+           string whatString = SATprobleminfoString (problem,detail);
            MIL << whatString << endl;
            MIL << "------------------------------------" << endl;
-           ResolverProblem_Ptr resolverProblem = new ResolverProblem (whatString, "");
+           ResolverProblem_Ptr resolverProblem = new ResolverProblem (whatString, detail);
            solution = 0;
            while ((solution = solver_next_solution(_solv, problem, solution)) != 0) {
                element = 0;

diff --git a/zypp/sat/SATResolver.h b/zypp/sat/SATResolver.h
index 8f5ea92..9a77fe9 100644 (file)
--- a/zypp/sat/SATResolver.h
+++ b/zypp/sat/SATResolver.h
@@ -80,7 +80,7 @@ class SATResolver : public base::ReferenceCounted, private base::NonCopyable {
     bool _dosplitprovides;             /* true: consider legacy split provides */
     
     // ---------------------------------- methods
-    std::string SATprobleminfoString (Id problem);
+    std::string SATprobleminfoString (Id problem, std::string &detail);
 
   public: