add a ConstructedBy member to the PackageSet which can be used by the

e.g. FromString to tell the caller if the string was an exact match
or found by regex or task. The two later ones can match packages for
which we want to ignore failures in the VersionSet

cmdline/cacheset.cc

@@ -33,13 +33,13 @@ PackageSet PackageSet::FromTask(pkgCacheFile &Cache, std::string pattern, CacheS
 	}
 
 	if (pattern[pattern.length() -1] != '^')
-		return APT::PackageSet();
+		return APT::PackageSet(TASK);
 	pattern.erase(pattern.length()-1);
 
 	if (unlikely(Cache.GetPkgCache() == 0 || Cache.GetDepCache() == 0))
-		return APT::PackageSet();
+		return APT::PackageSet(TASK);
 
-	PackageSet pkgset;
+	PackageSet pkgset(TASK);
 	// get the records
 	pkgRecords Recs(Cache);
 
@@ -85,7 +85,7 @@ PackageSet PackageSet::FromTask(pkgCacheFile &Cache, std::string pattern, CacheS
 PackageSet PackageSet::FromRegEx(pkgCacheFile &Cache, std::string pattern, CacheSetHelper &helper) {
 	static const char * const isregex = ".?+*|[^$";
 	if (pattern.find_first_of(isregex) == std::string::npos)
-		return PackageSet();
+		return PackageSet(REGEX);
 
 	size_t archfound = pattern.find_last_of(':');
 	std::string arch = "native";
@@ -103,13 +103,13 @@ PackageSet PackageSet::FromRegEx(pkgCacheFile &Cache, std::string pattern, Cache
 		char Error[300];
 		regerror(Res, &Pattern, Error, sizeof(Error));
 		_error->Error(_("Regex compilation error - %s"), Error);
-		return PackageSet();
+		return PackageSet(REGEX);
 	}
 
 	if (unlikely(Cache.GetPkgCache() == 0))
-		return PackageSet();
+		return PackageSet(REGEX);
 
-	PackageSet pkgset;
+	PackageSet pkgset(REGEX);
 	for (pkgCache::GrpIterator Grp = Cache.GetPkgCache()->GrpBegin(); Grp.end() == false; ++Grp)
 	{
 		if (regexec(&Pattern, Grp.Name(), 0, 0, 0) != 0)
@@ -318,8 +318,12 @@ APT::VersionSet VersionSet::FromString(pkgCacheFile &Cache, std::string pkg,
 	}
 
 	VersionSet verset;
+	bool errors = true;
+	if (pkgset.getConstructor() != PackageSet::UNKNOWN)
+		errors = helper.showErrors(false);
 	for (PackageSet::const_iterator P = pkgset.begin();
 	     P != pkgset.end(); ++P) {
+		helper.canNotFindCandidateVer(Cache, P);
 		if (vertag == string::npos) {
 			verset.insert(VersionSet::FromPackage(Cache, P, fallback, helper));
 			continue;
@@ -348,6 +352,8 @@ APT::VersionSet VersionSet::FromString(pkgCacheFile &Cache, std::string pkg,
 		helper.showSelectedVersion(P, V, ver, verIsRel);
 		verset.insert(V);
 	}
+	if (pkgset.getConstructor() != PackageSet::UNKNOWN)
+		helper.showErrors(errors);
 	return verset;
 }
 									/*}}}*/
@@ -487,7 +493,7 @@ pkgCache::VerIterator CacheSetHelper::canNotFindNewestVer(pkgCacheFile &Cache,
 		pkgCache::PkgIterator const &Pkg) {
 	if (ShowError == true)
 		_error->Error(_("Can't select newest version from package '%s' as it is purely virtual"), Pkg.FullName(true).c_str());
-	return pkgCache::VerIterator(Cache);
+	return pkgCache::VerIterator(Cache, 0);
 }
 									/*}}}*/
 // canNotFindCandidateVer						/*{{{*/
@@ -495,7 +501,7 @@ pkgCache::VerIterator CacheSetHelper::canNotFindCandidateVer(pkgCacheFile &Cache
 		pkgCache::PkgIterator const &Pkg) {
 	if (ShowError == true)
 		_error->Error(_("Can't select candidate version from package %s as it has no candidate"), Pkg.FullName(true).c_str());
-	return pkgCache::VerIterator(Cache);
+	return pkgCache::VerIterator(Cache, 0);
 }
 									/*}}}*/
 // canNotFindInstalledVer						/*{{{*/
@@ -503,7 +509,7 @@ pkgCache::VerIterator CacheSetHelper::canNotFindInstalledVer(pkgCacheFile &Cache
 		pkgCache::PkgIterator const &Pkg) {
 	if (ShowError == true)
 		_error->Error(_("Can't select installed version from package %s as it is not installed"), Pkg.FullName(true).c_str());
-	return pkgCache::VerIterator(Cache);
+	return pkgCache::VerIterator(Cache, 0);
 }
 									/*}}}*/
 }

cmdline/cacheset.h

@@ -117,7 +117,7 @@ public:									/*{{{*/
 	    packages chosen cause of the given task.
 	    \param Cache the packages are in
 	    \param pattern name of the task
-	    \param out stream to print the notice to */
+	    \param helper responsible for error and message handling */
 	static APT::PackageSet FromTask(pkgCacheFile &Cache, std::string pattern, CacheSetHelper &helper);
 	static APT::PackageSet FromTask(pkgCacheFile &Cache, std::string const &pattern) {
 		CacheSetHelper helper;
@@ -131,7 +131,7 @@ public:									/*{{{*/
 	    packages chosen cause of the given package.
 	    \param Cache the packages are in
 	    \param pattern regular expression for package names
-	    \param out stream to print the notice to */
+	    \param helper responsible for error and message handling */
 	static APT::PackageSet FromRegEx(pkgCacheFile &Cache, std::string pattern, CacheSetHelper &helper);
 	static APT::PackageSet FromRegEx(pkgCacheFile &Cache, std::string const &pattern) {
 		CacheSetHelper helper;
@@ -142,7 +142,7 @@ public:									/*{{{*/
 
 	    \param Cache the packages are in
 	    \param string String the package name(s) should be extracted from
-	    \param out stream to print various notices to */
+	    \param helper responsible for error and message handling */
 	static APT::PackageSet FromString(pkgCacheFile &Cache, std::string const &string, CacheSetHelper &helper);
 	static APT::PackageSet FromString(pkgCacheFile &Cache, std::string const &string) {
 		CacheSetHelper helper;
@@ -153,7 +153,7 @@ public:									/*{{{*/
 
 	    \param Cache the package is in
 	    \param string String the package name should be extracted from
-	    \param out stream to print various notices to */
+	    \param helper responsible for error and message handling */
 	static pkgCache::PkgIterator FromName(pkgCacheFile &Cache, std::string const &string, CacheSetHelper &helper);
 	static pkgCache::PkgIterator FromName(pkgCacheFile &Cache, std::string const &string) {
 		CacheSetHelper helper;
@@ -166,7 +166,7 @@ public:									/*{{{*/
 	    No special package command is supported, just plain names.
 	    \param Cache the packages are in
 	    \param cmdline Command line the package names should be extracted from
-	    \param out stream to print various notices to */
+	    \param helper responsible for error and message handling */
 	static APT::PackageSet FromCommandLine(pkgCacheFile &Cache, const char **cmdline, CacheSetHelper &helper);
 	static APT::PackageSet FromCommandLine(pkgCacheFile &Cache, const char **cmdline) {
 		CacheSetHelper helper;
@@ -181,6 +181,17 @@ public:									/*{{{*/
 		Modifier (unsigned short const &id, const char * const alias, Position const &pos) : ID(id), Alias(alias), Pos(pos) {};
 	};
 
+	/** \brief group packages by a action modifiers
+
+	    At some point it is needed to get from the same commandline
+	    different package sets grouped by a modifier. Take
+		apt-get install apt awesome-
+	    as an example.
+	    \param Cache the packages are in
+	    \param cmdline Command line the package names should be extracted from
+	    \param mods list of modifiers the method should accept
+	    \param fallback the default modifier group for a package
+	    \param helper responsible for error and message handling */
 	static std::map<unsigned short, PackageSet> GroupedFromCommandLine(
 		pkgCacheFile &Cache, const char **cmdline,
 		std::list<PackageSet::Modifier> const &mods,
@@ -193,6 +204,15 @@ public:									/*{{{*/
 		return APT::PackageSet::GroupedFromCommandLine(Cache, cmdline,
 				mods, fallback, helper);
 	}
+
+	enum Constructor { UNKNOWN, REGEX, TASK };
+	Constructor getConstructor() const { return ConstructedBy; };
+
+	PackageSet() : ConstructedBy(UNKNOWN) {};
+	PackageSet(Constructor const &by) : ConstructedBy(by) {};
+									/*}}}*/
+private:								/*{{{*/
+	Constructor ConstructedBy;
 									/*}}}*/
 };									/*}}}*/
 class VersionSet : public std::set<pkgCache::VerIterator> {		/*{{{*/
@@ -269,7 +289,7 @@ public:									/*{{{*/
 	    non specifically requested  and executes regex's if needed on names.
 	    \param Cache the packages and versions are in
 	    \param cmdline Command line the versions should be extracted from
-	    \param out stream to print various notices to */
+	    \param helper responsible for error and message handling */
 	static APT::VersionSet FromCommandLine(pkgCacheFile &Cache, const char **cmdline,
 			APT::VersionSet::Version const &fallback, CacheSetHelper &helper);
 	static APT::VersionSet FromCommandLine(pkgCacheFile &Cache, const char **cmdline,
@@ -299,8 +319,16 @@ public:									/*{{{*/
 	    \param P the package in question
 	    \param fallback the version(s) you want to get
 	    \param helper the helper used for display and error handling */
-	static VersionSet FromPackage(pkgCacheFile &Cache, pkgCache::PkgIterator const &P,
+	static APT::VersionSet FromPackage(pkgCacheFile &Cache, pkgCache::PkgIterator const &P,
 		VersionSet::Version const &fallback, CacheSetHelper &helper);
+	static APT::VersionSet FromPackage(pkgCacheFile &Cache, pkgCache::PkgIterator const &P,
+			APT::VersionSet::Version const &fallback) {
+		CacheSetHelper helper;
+		return APT::VersionSet::FromPackage(Cache, P, fallback, helper);
+	}
+	static APT::VersionSet FromPackage(pkgCacheFile &Cache, pkgCache::PkgIterator const &P) {
+		return APT::VersionSet::FromPackage(Cache, P, CANDINST);
+	}
 
 	struct Modifier {
 		enum Position { NONE, PREFIX, POSTFIX };