Merge branch 'pu/patterns' into 'master'

Package patterns

See merge request apt-team/apt!74

12 files changed, 1028 insertions, 9 deletions

diff --git a/apt-pkg/cachefilter-patterns.cc b/apt-pkg/cachefilter-patterns.cc
new file mode 100644
index 000000000..bf6166ee4
--- /dev/null
+++ b/apt-pkg/cachefilter-patterns.cc
@@ -0,0 +1,306 @@
+/*
+ * cachefilter-patterns.cc - Parser for aptitude-style patterns
+ *
+ * Copyright (c) 2019 Canonical Ltd
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <apt-pkg/cachefilter-patterns.h>
+
+namespace APT
+{
+namespace Internal
+{
+
+template <class... Args>
+std::string rstrprintf(Args... args)
+{
+   std::string str;
+   strprintf(str, std::forward<Args>(args)...);
+   return str;
+}
+
+// Parse a complete pattern, make sure it's the entire input
+std::unique_ptr<PatternTreeParser::Node> PatternTreeParser::parseTop()
+{
+   skipSpace();
+   auto node = parse();
+   skipSpace();
+
+   if (node->end != sentence.size())
+   {
+      Node node2;
+
+      node2.start = node->end;
+      node2.end = sentence.size();
+      throw Error{node2, "Expected end of file"};
+   }
+
+   return node;
+}
+
+// Parse any pattern
+std::unique_ptr<PatternTreeParser::Node> PatternTreeParser::parse()
+{
+   std::unique_ptr<Node> node;
+   if ((node = parsePattern()) != nullptr)
+      return node;
+   if ((node = parseQuotedWord()) != nullptr)
+      return node;
+   if ((node = parseWord()) != nullptr)
+      return node;
+
+   Node eNode;
+   eNode.end = eNode.start = state.offset;
+   throw Error{eNode, "Expected pattern, quoted word, or word"};
+}
+
+// Parse a list pattern (or function call pattern)
+std::unique_ptr<PatternTreeParser::Node> PatternTreeParser::parsePattern()
+{
+   static const APT::StringView CHARS("0123456789"
+				      "abcdefghijklmnopqrstuvwxyz"
+				      "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+				      "-");
+   if (sentence[state.offset] != '?')
+      return nullptr;
+
+   auto node = std::make_unique<PatternNode>();
+   node->end = node->start = state.offset;
+   state.offset++;
+
+   while (CHARS.find(sentence[state.offset]) != APT::StringView::npos)
+   {
+      ++state.offset;
+   }
+
+   node->term = sentence.substr(node->start, state.offset - node->start);
+
+   node->end = skipSpace();
+   // We don't have any arguments, return node;
+   if (sentence[state.offset] != '(')
+      return node;
+   node->end = ++state.offset;
+   skipSpace();
+
+   node->haveArgumentList = true;
+
+   // Empty argument list, return
+   if (sentence[state.offset] == ')')
+   {
+      node->end = ++state.offset;
+      return node;
+   }
+
+   node->arguments.push_back(parse());
+   skipSpace();
+   while (sentence[state.offset] == ',')
+   {
+      ++state.offset;
+      skipSpace();
+      // This was a trailing comma - allow it and break the loop
+      if (sentence[state.offset] == ')')
+	 break;
+      node->arguments.push_back(parse());
+      skipSpace();
+   }
+
+   node->end = state.offset;
+   if (sentence[state.offset] != ')')
+      throw Error{node->arguments.empty() ? *node : *node->arguments[node->arguments.size() - 1],
+		  rstrprintf("Expected closing parenthesis or comma after last argument, received %c", sentence[state.offset])};
+
+   node->end = ++state.offset;
+   return node;
+}
+
+// Parse a quoted word atom
+std::unique_ptr<PatternTreeParser::Node> PatternTreeParser::parseQuotedWord()
+{
+   if (sentence[state.offset] != '"')
+      return nullptr;
+
+   auto node = std::make_unique<WordNode>();
+   node->start = state.offset;
+
+   // Eat beginning of string
+   state.offset++;
+
+   while (sentence[state.offset] != '"' && sentence[state.offset] != '\0')
+      state.offset++;
+
+   // End of string
+   if (sentence[state.offset] != '"')
+      throw Error{*node, "Could not find end of string"};
+   state.offset++;
+
+   node->end = state.offset;
+   node->word = sentence.substr(node->start + 1, node->end - node->start - 2);
+
+   return node;
+}
+
+// Parse a bare word atom
+std::unique_ptr<PatternTreeParser::Node> PatternTreeParser::parseWord()
+{
+   static const APT::StringView DISALLOWED_START("?~,()\0", 6);
+   static const APT::StringView DISALLOWED(",()\0", 4);
+   if (DISALLOWED_START.find(sentence[state.offset]) != APT::StringView::npos)
+      return nullptr;
+
+   auto node = std::make_unique<WordNode>();
+   node->start = state.offset;
+
+   while (DISALLOWED.find(sentence[state.offset]) == APT::StringView::npos)
+      state.offset++;
+
+   node->end = state.offset;
+   node->word = sentence.substr(node->start, node->end - node->start);
+   return node;
+}
+
+// Rendering of the tree in JSON for debugging
+std::ostream &PatternTreeParser::PatternNode::render(std::ostream &os)
+{
+   os << "{"
+      << "\"term\": \"" << term.to_string() << "\",\n"
+      << "\"arguments\": [\n";
+   for (auto &node : arguments)
+      node->render(os) << "," << std::endl;
+   os << "null]\n";
+   os << "}\n";
+   return os;
+}
+
+std::ostream &PatternTreeParser::WordNode::render(std::ostream &os)
+{
+   os << '"' << word.to_string() << '"';
+   return os;
+}
+
+std::nullptr_t PatternTreeParser::Node::error(std::string message)
+{
+   throw Error{*this, message};
+}
+
+bool PatternTreeParser::PatternNode::matches(APT::StringView name, int min, int max)
+{
+   if (name != term)
+      return false;
+   if (max != 0 && !haveArgumentList)
+      error(rstrprintf("%s expects an argument list", term.to_string().c_str()));
+   if (max == 0 && haveArgumentList)
+      error(rstrprintf("%s does not expect an argument list", term.to_string().c_str()));
+   if (min >= 0 && min == max && (arguments.size() != size_t(min)))
+      error(rstrprintf("%s expects %d arguments, but received %d arguments", term.to_string().c_str(), min, arguments.size()));
+   if (min >= 0 && arguments.size() < size_t(min))
+      error(rstrprintf("%s expects at least %d arguments, but received %d arguments", term.to_string().c_str(), min, arguments.size()));
+   if (max >= 0 && arguments.size() > size_t(max))
+      error(rstrprintf("%s expects at most %d arguments, but received %d arguments", term.to_string().c_str(), max, arguments.size()));
+   return true;
+}
+
+std::unique_ptr<APT::CacheFilter::Matcher> PatternParser::aPattern(std::unique_ptr<PatternTreeParser::Node> &nodeP)
+{
+   assert(nodeP != nullptr);
+   auto node = dynamic_cast<PatternTreeParser::PatternNode *>(nodeP.get());
+   if (node == nullptr)
+      nodeP->error("Expected a pattern");
+
+   if (node->matches("?architecture", 1, 1))
+      return std::make_unique<APT::CacheFilter::PackageArchitectureMatchesSpecification>(aWord(node->arguments[0]));
+   if (node->matches("?automatic", 0, 0))
+      return std::make_unique<Patterns::PackageIsAutomatic>(file);
+   if (node->matches("?broken", 0, 0))
+      return std::make_unique<Patterns::PackageIsBroken>(file);
+   if (node->matches("?config-files", 0, 0))
+      return std::make_unique<Patterns::PackageIsConfigFiles>();
+   if (node->matches("?essential", 0, 0))
+      return std::make_unique<Patterns::PackageIsEssential>();
+   if (node->matches("?exact-name", 1, 1))
+      return std::make_unique<Patterns::PackageHasExactName>(aWord(node->arguments[0]));
+   if (node->matches("?false", 0, 0))
+      return std::make_unique<APT::CacheFilter::FalseMatcher>();
+   if (node->matches("?garbage", 0, 0))
+      return std::make_unique<Patterns::PackageIsGarbage>(file);
+   if (node->matches("?installed", 0, 0))
+      return std::make_unique<Patterns::PackageIsInstalled>(file);
+   if (node->matches("?name", 1, 1))
+      return std::make_unique<APT::CacheFilter::PackageNameMatchesRegEx>(aWord(node->arguments[0]));
+   if (node->matches("?not", 1, 1))
+      return std::make_unique<APT::CacheFilter::NOTMatcher>(aPattern(node->arguments[0]).release());
+   if (node->matches("?obsolete", 0, 0))
+      return std::make_unique<Patterns::PackageIsObsolete>();
+   if (node->matches("?true", 0, 0))
+      return std::make_unique<APT::CacheFilter::TrueMatcher>();
+   if (node->matches("?upgradable", 0, 0))
+      return std::make_unique<Patterns::PackageIsUpgradable>(file);
+   if (node->matches("?virtual", 0, 0))
+      return std::make_unique<Patterns::PackageIsVirtual>();
+   if (node->matches("?x-name-fnmatch", 1, 1))
+      return std::make_unique<APT::CacheFilter::PackageNameMatchesFnmatch>(aWord(node->arguments[0]));
+
+   // Variable argument patterns
+   if (node->matches("?and", 0, -1))
+   {
+      auto pattern = std::make_unique<APT::CacheFilter::ANDMatcher>();
+      for (auto &arg : node->arguments)
+	 pattern->AND(aPattern(arg).release());
+      return pattern;
+   }
+   if (node->matches("?or", 0, -1))
+   {
+      auto pattern = std::make_unique<APT::CacheFilter::ORMatcher>();
+
+      for (auto &arg : node->arguments)
+	 pattern->OR(aPattern(arg).release());
+      return pattern;
+   }
+
+   node->error(rstrprintf("Unrecognized pattern '%s'", node->term.to_string().c_str()));
+
+   return nullptr;
+}
+
+std::string PatternParser::aWord(std::unique_ptr<PatternTreeParser::Node> &nodeP)
+{
+   assert(nodeP != nullptr);
+   auto node = dynamic_cast<PatternTreeParser::WordNode *>(nodeP.get());
+   if (node == nullptr)
+      nodeP->error("Expected a word");
+   return node->word.to_string();
+}
+
+} // namespace Internal
+
+// The bridge into the public world
+std::unique_ptr<APT::CacheFilter::Matcher> APT::CacheFilter::ParsePattern(APT::StringView pattern, pkgCacheFile *file)
+{
+   if (file != nullptr && !file->BuildDepCache())
+      return nullptr;
+
+   try
+   {
+      auto top = APT::Internal::PatternTreeParser(pattern).parseTop();
+      APT::Internal::PatternParser parser{file};
+      return parser.aPattern(top);
+   }
+   catch (APT::Internal::PatternTreeParser::Error &e)
+   {
+      std::stringstream ss;
+      ss << "input:" << e.location.start << "-" << e.location.end << ": error: " << e.message << "\n";
+      ss << pattern.to_string() << "\n";
+      for (size_t i = 0; i < e.location.start; i++)
+	 ss << " ";
+      for (size_t i = e.location.start; i < e.location.end; i++)
+	 ss << "^";
+
+      ss << "\n";
+
+      _error->Error("%s", ss.str().c_str());
+      return nullptr;
+   }
+}
+
+} // namespace APT
diff --git a/apt-pkg/cachefilter-patterns.h b/apt-pkg/cachefilter-patterns.h
new file mode 100644
index 000000000..d37da815f
--- /dev/null
+++ b/apt-pkg/cachefilter-patterns.h
@@ -0,0 +1,235 @@
+/*
+ * cachefilter-patterns.h - Pattern parser and additional patterns as matchers
+ *
+ * Copyright (c) 2019 Canonical Ltd
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#ifndef APT_CACHEFILTER_PATTERNS_H
+#define APT_CACHEFILTER_PATTERNS_H
+#include <apt-pkg/cachefile.h>
+#include <apt-pkg/cachefilter.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/string_view.h>
+#include <apt-pkg/strutl.h>
+#include <iostream>
+#include <memory>
+#include <sstream>
+#include <string>
+#include <vector>
+#include <assert.h>
+namespace APT
+{
+
+namespace Internal
+{
+/**
+ * \brief PatternTreeParser parses the given sentence into a parse tree.
+ *
+ * The parse tree consists of nodes:
+ *  - Word nodes which contains words or quoted words
+ *  - Patterns, which represent ?foo and ?foo(...) patterns
+ */
+struct PatternTreeParser
+{
+
+   struct Node
+   {
+      size_t start = 0;
+      size_t end = 0;
+
+      virtual std::ostream &render(std::ostream &os) { return os; };
+      std::nullptr_t error(std::string message);
+   };
+
+   struct Error : public std::exception
+   {
+      Node location;
+      std::string message;
+
+      Error(Node location, std::string message) : location(location), message(message) {}
+      const char *what() const throw() override { return message.c_str(); }
+   };
+
+   struct PatternNode : public Node
+   {
+      APT::StringView term;
+      std::vector<std::unique_ptr<Node>> arguments;
+      bool haveArgumentList = false;
+
+      std::ostream &render(std::ostream &stream) override;
+      bool matches(APT::StringView name, int min, int max);
+   };
+
+   struct WordNode : public Node
+   {
+      APT::StringView word;
+      bool quoted = false;
+      std::ostream &render(std::ostream &stream) override;
+   };
+
+   struct State
+   {
+      off_t offset = 0;
+   };
+
+   APT::StringView sentence;
+   State state;
+
+   PatternTreeParser(APT::StringView sentence) : sentence(sentence){};
+   off_t skipSpace()
+   {
+      while (sentence[state.offset] == ' ' || sentence[state.offset] == '\t' || sentence[state.offset] == '\r' || sentence[state.offset] == '\n')
+	 state.offset++;
+      return state.offset;
+   };
+
+   /// \brief Parse a complete pattern
+   ///
+   /// There may not be anything before or after the pattern, except for
+   /// whitespace.
+   std::unique_ptr<Node> parseTop();
+
+   private:
+   std::unique_ptr<Node> parse();
+   std::unique_ptr<Node> parsePattern();
+   std::unique_ptr<Node> parseWord();
+   std::unique_ptr<Node> parseQuotedWord();
+};
+
+/**
+ * \brief PatternParser parses the given sentence into a parse tree.
+ *
+ * The parse tree consists of nodes:
+ *  - Word nodes which contains words or quoted words
+ *  - Patterns, which represent ?foo and ?foo(...) patterns
+ */
+struct PatternParser
+{
+   pkgCacheFile *file;
+
+   std::unique_ptr<APT::CacheFilter::Matcher> aPattern(std::unique_ptr<PatternTreeParser::Node> &nodeP);
+   std::string aWord(std::unique_ptr<PatternTreeParser::Node> &nodeP);
+};
+
+namespace Patterns
+{
+using namespace APT::CacheFilter;
+
+struct PackageIsAutomatic : public PackageMatcher
+{
+   pkgCacheFile *Cache;
+   explicit PackageIsAutomatic(pkgCacheFile *Cache) : Cache(Cache) {}
+   bool operator()(pkgCache::PkgIterator const &Pkg) override
+   {
+      assert(Cache != nullptr);
+      return ((*Cache)[Pkg].Flags & pkgCache::Flag::Auto) != 0;
+   }
+};
+
+struct PackageIsBroken : public PackageMatcher
+{
+   pkgCacheFile *Cache;
+   explicit PackageIsBroken(pkgCacheFile *Cache) : Cache(Cache) {}
+   bool operator()(pkgCache::PkgIterator const &Pkg) override
+   {
+      assert(Cache != nullptr);
+      auto state = (*Cache)[Pkg];
+      return state.InstBroken() || state.NowBroken();
+   }
+};
+
+struct PackageIsConfigFiles : public PackageMatcher
+{
+   bool operator()(pkgCache::PkgIterator const &Pkg) override
+   {
+      return Pkg->CurrentState == pkgCache::State::ConfigFiles;
+   }
+};
+
+struct PackageIsGarbage : public PackageMatcher
+{
+   pkgCacheFile *Cache;
+   explicit PackageIsGarbage(pkgCacheFile *Cache) : Cache(Cache) {}
+   bool operator()(pkgCache::PkgIterator const &Pkg) override
+   {
+      assert(Cache != nullptr);
+      return (*Cache)[Pkg].Garbage;
+   }
+};
+struct PackageIsEssential : public PackageMatcher
+{
+   bool operator()(pkgCache::PkgIterator const &Pkg) override
+   {
+      return (Pkg->Flags & pkgCache::Flag::Essential) != 0;
+   }
+};
+
+struct PackageHasExactName : public PackageMatcher
+{
+   std::string name;
+   explicit PackageHasExactName(std::string name) : name(name) {}
+   bool operator()(pkgCache::PkgIterator const &Pkg) override
+   {
+      return Pkg.Name() == name;
+   }
+};
+
+struct PackageIsInstalled : public PackageMatcher
+{
+   pkgCacheFile *Cache;
+   explicit PackageIsInstalled(pkgCacheFile *Cache) : Cache(Cache) {}
+   bool operator()(pkgCache::PkgIterator const &Pkg) override
+   {
+      assert(Cache != nullptr);
+      return Pkg->CurrentVer != 0;
+   }
+};
+
+struct PackageIsObsolete : public PackageMatcher
+{
+   bool operator()(pkgCache::PkgIterator const &pkg) override
+   {
+      // This code can be written without loops, as aptitude does, but it
+      // is far less readable.
+      if (pkg.CurrentVer().end())
+	 return false;
+
+      // See if there is any version that exists in a repository,
+      // if so return false
+      for (auto ver = pkg.VersionList(); !ver.end(); ver++)
+      {
+	 for (auto file = ver.FileList(); !file.end(); file++)
+	 {
+	    if ((file.File()->Flags & pkgCache::Flag::NotSource) == 0)
+	       return false;
+	 }
+      }
+
+      return true;
+   }
+};
+
+struct PackageIsUpgradable : public PackageMatcher
+{
+   pkgCacheFile *Cache;
+   explicit PackageIsUpgradable(pkgCacheFile *Cache) : Cache(Cache) {}
+   bool operator()(pkgCache::PkgIterator const &Pkg) override
+   {
+      assert(Cache != nullptr);
+      return Pkg->CurrentVer != 0 && (*Cache)[Pkg].Upgradable();
+   }
+};
+
+struct PackageIsVirtual : public PackageMatcher
+{
+   bool operator()(pkgCache::PkgIterator const &Pkg) override
+   {
+      return Pkg->VersionList == 0;
+   }
+};
+} // namespace Patterns
+} // namespace Internal
+} // namespace APT
+#endif
diff --git a/apt-pkg/cachefilter.h b/apt-pkg/cachefilter.h
index 8a6c01341..3c6e1559d 100644
--- a/apt-pkg/cachefilter.h
+++ b/apt-pkg/cachefilter.h
@@ -7,7 +7,9 @@
 #define APT_CACHEFILTER_H
 // Include Files							/*{{{*/
 #include <apt-pkg/pkgcache.h>
+#include <apt-pkg/string_view.h>
 
+#include <memory>
 #include <string>
 #include <vector>
 
@@ -145,6 +147,8 @@ public:
 };
 									/*}}}*/
 
+/// \brief Parse a pattern, return nullptr or pattern
+std::unique_ptr<APT::CacheFilter::Matcher> ParsePattern(APT::StringView pattern, pkgCacheFile *file);
 }
 }
 #endif
diff --git a/apt-pkg/cacheset.cc b/apt-pkg/cacheset.cc
index 789727266..dd55edb4e 100644
--- a/apt-pkg/cacheset.cc
+++ b/apt-pkg/cacheset.cc
@@ -46,6 +46,7 @@ bool CacheSetHelper::PackageFrom(enum PkgSelector const select, PackageContainer
 	case FNMATCH: return PackageFromFnmatch(pci, Cache, pattern);
 	case PACKAGENAME: return PackageFromPackageName(pci, Cache, pattern);
 	case STRING: return PackageFromString(pci, Cache, pattern);
+	case PATTERN: return PackageFromPattern(pci, Cache, pattern);
 	}
 	return false;
 }
@@ -281,13 +282,33 @@ bool CacheSetHelper::PackageFromPackageName(PackageContainerInterface * const pc
 	pci->insert(Pkg);
 	return true;
 }
+
+bool CacheSetHelper::PackageFromPattern(PackageContainerInterface *const pci, pkgCacheFile &Cache, std::string const &pattern)
+{
+   if (pattern.size() < 1 || pattern[0] != '?')
+      return false;
+
+   auto compiledPattern = APT::CacheFilter::ParsePattern(pattern, &Cache);
+   if (!compiledPattern)
+      return false;
+
+   for (pkgCache::PkgIterator Pkg = Cache->PkgBegin(); Pkg.end() == false; ++Pkg)
+   {
+      if ((*compiledPattern)(Pkg) == false)
+	 continue;
+
+      pci->insert(Pkg);
+   }
+   return true;
+}
 									/*}}}*/
 // PackageFromString - Return all packages matching a specific string	/*{{{*/
 bool CacheSetHelper::PackageFromString(PackageContainerInterface * const pci, pkgCacheFile &Cache, std::string const &str) {
 	bool found = true;
 	_error->PushToStack();
 
-	if (PackageFrom(CacheSetHelper::PACKAGENAME, pci, Cache, str) == false &&
+	if (PackageFrom(CacheSetHelper::PATTERN, pci, Cache, str) == false &&
+	     PackageFrom(CacheSetHelper::PACKAGENAME, pci, Cache, str) == false &&
 		 PackageFrom(CacheSetHelper::TASK, pci, Cache, str) == false &&
 		 // FIXME: hm, hm, regexp/fnmatch incompatible?
 		 PackageFrom(CacheSetHelper::FNMATCH, pci, Cache, str) == false &&
@@ -686,6 +707,7 @@ void CacheSetHelper::canNotFindPackage(enum PkgSelector const select,
 	case FNMATCH: canNotFindFnmatch(pci, Cache, pattern); break;
 	case PACKAGENAME: canNotFindPackage(pci, Cache, pattern); break;
 	case STRING: canNotFindPackage(pci, Cache, pattern); break;
+	case PATTERN: canNotFindPackage(pci, Cache, pattern); break;
 	case UNKNOWN: break;
 	}
 }
@@ -822,6 +844,7 @@ void CacheSetHelper::showPackageSelection(pkgCache::PkgIterator const &pkg, enum
 	case REGEX: showRegExSelection(pkg, pattern); break;
 	case TASK: showTaskSelection(pkg, pattern); break;
 	case FNMATCH: showFnmatchSelection(pkg, pattern); break;
+	case PATTERN: showPatternSelection(pkg, pattern); break;
 	case PACKAGENAME: /* no surprises here */ break;
 	case STRING: /* handled by the special cases */ break;
 	case UNKNOWN: break;
@@ -842,6 +865,12 @@ void CacheSetHelper::showFnmatchSelection(pkgCache::PkgIterator const &/*pkg*/,
                                          std::string const &/*pattern*/) {
 }
 									/*}}}*/
+// showPatternSelection							/*{{{*/
+void CacheSetHelper::showPatternSelection(pkgCache::PkgIterator const & /*pkg*/,
+					  std::string const & /*pattern*/)
+{
+}
+									/*}}}*/
 									/*}}}*/
 // showVersionSelection							/*{{{*/
 void CacheSetHelper::showVersionSelection(pkgCache::PkgIterator const &Pkg,
diff --git a/apt-pkg/cacheset.h b/apt-pkg/cacheset.h
index 489fb6220..6023b861d 100644
--- a/apt-pkg/cacheset.h
+++ b/apt-pkg/cacheset.h
@@ -52,7 +52,7 @@ public:									/*{{{*/
 		GlobalError::MsgType ErrorType = GlobalError::ERROR);
 	virtual ~CacheSetHelper();
 
-	enum PkgSelector { UNKNOWN, REGEX, TASK, FNMATCH, PACKAGENAME, STRING };
+	enum PkgSelector { UNKNOWN, REGEX, TASK, FNMATCH, PACKAGENAME, STRING, PATTERN };
 
 	virtual bool PackageFrom(enum PkgSelector const select, PackageContainerInterface * const pci, pkgCacheFile &Cache, std::string const &pattern);
 
@@ -172,10 +172,12 @@ protected:
 	bool PackageFromFnmatch(PackageContainerInterface * const pci, pkgCacheFile &Cache, std::string pattern);
 	bool PackageFromPackageName(PackageContainerInterface * const pci, pkgCacheFile &Cache, std::string pattern);
 	bool PackageFromString(PackageContainerInterface * const pci, pkgCacheFile &Cache, std::string const &pattern);
+	bool PackageFromPattern(PackageContainerInterface * const pci, pkgCacheFile &Cache, std::string const &pattern);
 private:
 	void showTaskSelection(pkgCache::PkgIterator const &pkg, std::string const &pattern);
 	void showRegExSelection(pkgCache::PkgIterator const &pkg, std::string const &pattern);
 	void showFnmatchSelection(pkgCache::PkgIterator const &pkg, std::string const &pattern);
+	void showPatternSelection(pkgCache::PkgIterator const &pkg, std::string const &pattern);
 	void canNotFindTask(PackageContainerInterface *const pci, pkgCacheFile &Cache, std::string pattern);
 	void canNotFindRegEx(PackageContainerInterface *const pci, pkgCacheFile &Cache, std::string pattern);
 	void canNotFindFnmatch(PackageContainerInterface *const pci, pkgCacheFile &Cache, std::string pattern);
@@ -739,6 +741,8 @@ public:
 			       std::string pkg, CacheSetHelper::VerSelector const fallback, CacheSetHelper &helper,
 			       bool const onlyFromName = false);
 
+	static bool FromPattern(VersionContainerInterface *const vci, pkgCacheFile &Cache,
+				std::string pkg, CacheSetHelper::VerSelector const fallback, CacheSetHelper &helper);
 
 	static bool FromPackage(VersionContainerInterface * const vci, pkgCacheFile &Cache,
 				pkgCache::PkgIterator const &P, CacheSetHelper::VerSelector const fallback,
diff --git a/apt-private/private-list.cc b/apt-private/private-list.cc
index 7c8c89777..6071129a7 100644
--- a/apt-private/private-list.cc
+++ b/apt-private/private-list.cc
@@ -39,17 +39,26 @@ struct PackageSortAlphabetic						/*{{{*/
 
 class PackageNameMatcher : public Matcher
 {
+   pkgCacheFile &cacheFile;
   public:
-   explicit PackageNameMatcher(const char **patterns)
+   explicit PackageNameMatcher(pkgCacheFile &cacheFile, const char **patterns)
+   : cacheFile(cacheFile)
    {
       for(int i=0; patterns[i] != NULL; ++i)
       {
          std::string pattern = patterns[i];
-         APT::CacheFilter::PackageMatcher *cachefilter = NULL;
-         if(_config->FindB("APT::Cmd::Use-Regexp", false) == true)
+         APT::CacheFilter::Matcher *cachefilter = NULL;
+         if (pattern.size() > 0 && pattern[0] == '?')
+            cachefilter = APT::CacheFilter::ParsePattern(pattern, &cacheFile).release();
+         else if(_config->FindB("APT::Cmd::Use-Regexp", false) == true)
             cachefilter = new APT::CacheFilter::PackageNameMatchesRegEx(pattern);
          else
             cachefilter = new APT::CacheFilter::PackageNameMatchesFnmatch(pattern);
+
+         if (cachefilter == nullptr) {
+            return;
+            filters.clear();
+         }
          filters.push_back(cachefilter);
       }
    }
@@ -62,7 +71,7 @@ class PackageNameMatcher : public Matcher
    {
       for(J=filters.begin(); J != filters.end(); ++J)
       {
-         APT::CacheFilter::PackageMatcher *cachefilter = *J;
+         APT::CacheFilter::Matcher *cachefilter = *J;
          if((*cachefilter)(P)) 
             return true;
       }
@@ -70,8 +79,8 @@ class PackageNameMatcher : public Matcher
    }
 
 private:
-   std::vector<APT::CacheFilter::PackageMatcher*> filters;   
-   std::vector<APT::CacheFilter::PackageMatcher*>::const_iterator J;
+   std::vector<APT::CacheFilter::Matcher*> filters;
+   std::vector<APT::CacheFilter::Matcher*>::const_iterator J;
    #undef PackageMatcher
 };
 									/*}}}*/
@@ -111,7 +120,7 @@ bool DoList(CommandLine &Cmd)
    if (_config->FindB("APT::Cmd::List-Include-Summary", false) == true)
       format += "\n  ${Description}\n";
 
-   PackageNameMatcher matcher(patterns);
+   PackageNameMatcher matcher(CacheFile, patterns);
    LocalitySortedVersionSet bag;
    OpTextProgress progress(*_config);
    progress.OverallProgress(0,
diff --git a/debian/apt.install b/debian/apt.install
index f12eb240d..f745b3de5 100644
--- a/debian/apt.install
+++ b/debian/apt.install
@@ -37,6 +37,7 @@ usr/share/man/*/apt-get.*
 usr/share/man/*/apt-key.*
 usr/share/man/*/apt-mark.*
 usr/share/man/*/apt-secure.*
+usr/share/man/*/apt-patterns.*
 usr/share/man/*/apt-transport-http.*
 usr/share/man/*/apt-transport-https.*
 usr/share/man/*/apt-transport-mirror.*
diff --git a/doc/CMakeLists.txt b/doc/CMakeLists.txt
index 7cca4cf81..3060949e5 100644
--- a/doc/CMakeLists.txt
+++ b/doc/CMakeLists.txt
@@ -82,6 +82,7 @@ add_docbook(apt-man MANPAGE ALL
         apt-key.8.xml
         apt-mark.8.xml
         apt_preferences.5.xml
+        apt-patterns.7.xml
         apt-secure.8.xml
         apt-sortpkgs.1.xml
         apt-transport-http.1.xml
diff --git a/doc/apt-patterns.7.xml b/doc/apt-patterns.7.xml
new file mode 100644
index 000000000..efd4293dc
--- /dev/null
+++ b/doc/apt-patterns.7.xml
@@ -0,0 +1,161 @@
+<?xml version="1.0" encoding="utf-8" standalone="no"?>
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
+  "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
+<!ENTITY % aptent SYSTEM "apt.ent"> %aptent;
+<!ENTITY % aptverbatiment SYSTEM "apt-verbatim.ent"> %aptverbatiment;
+<!ENTITY % aptvendor SYSTEM "apt-vendor.ent"> %aptvendor;
+]>
+
+<refentry>
+ <refentryinfo>
+   &apt-author.jgunthorpe;
+   &apt-author.team;
+   &apt-email;
+   &apt-product;
+   <!-- The last update date -->
+   <date>2019-08-15T00:00:00Z</date>
+ </refentryinfo>
+
+ <refmeta>
+   <refentrytitle>apt-patterns</refentrytitle>
+   <manvolnum>7</manvolnum>
+   <refmiscinfo class="manual">APT</refmiscinfo>
+ </refmeta>
+
+ <!-- Man page title -->
+ <refnamediv>
+    <refname>apt-patterns</refname>
+    <refpurpose>Syntax and semantics of apt search patterns</refpurpose>
+ </refnamediv>
+
+ <refsect1><title>Description</title>
+   <para>
+   Starting with version 2.0, <command>APT</command> provides support for
+   patterns, which can be used to query the apt cache for packages.
+   </para>
+ </refsect1>
+
+ <refsect1>
+   <title>Logic patterns</title>
+   <para>
+      These patterns provide the basic means to combine other patterns into
+      more complex expressions, as well as <code>?true</code> and <code>?false</code>
+      patterns.
+   </para>
+   <variablelist>
+     <varlistentry><term><code>?and(PATTERN, PATTERN, ...)</code></term>
+     <listitem><para>Selects objects where all specified patterns match.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?false</code></term>
+     <listitem><para>Selects nothing.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?not(PATTERN)</code></term>
+     <listitem><para>Selects objects where PATTERN does not match.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?or(PATTERN, PATTERN, ...)</code></term>
+     <listitem><para>Selects objects where at least one of the specified patterns match.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?true</code></term>
+     <listitem><para>Selects all objects.</para></listitem>
+     </varlistentry>
+   </variablelist>
+ </refsect1>
+ <refsect1>
+   <title>Package patterns</title>
+   <para>
+   These patterns select specific packages.
+   </para>
+   <variablelist>
+     <varlistentry><term><code>?architecture(WILDCARD)</code></term>
+     <listitem><para>Selects packages matching the specified architecture, which may contain wildcards using any.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?automatic</code></term>
+     <listitem><para>Selects packages that were installed automatically.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?broken</code></term>
+     <listitem><para>Selects packages that have broken dependencies.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?config-files</code></term>
+     <listitem><para>Selects packages that are not fully installed, but have solely residual configuration files left.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?essential</code></term>
+     <listitem><para>Selects packages that have Essential: yes set in their control file.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?exact-name(NAME)</code></term>
+     <listitem><para>Selects packages with the exact specified name.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?garbage</code></term>
+     <listitem><para>Selects packages that can be removed automatically.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?installed</code></term>
+     <listitem><para>Selects packages that are currently installed.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?name(REGEX)</code></term>
+     <listitem><para>Selects packages where the name matches the given regular expression.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?obsolete</code></term>
+     <listitem><para>Selects packages that no longer exist in repositories.</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?upgradable</code></term>
+     <listitem><para>Selects packages that can be upgraded (have a newer candidate).</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>?virtual</code></term>
+     <listitem><para>Selects all virtual packages; that is packages without a version.
+      These exist when they are referenced somewhere in the archive,
+      for example because something depends on that name.</para></listitem>
+     </varlistentry>
+   </variablelist>
+ </refsect1>
+
+
+ <refsect1><title>Examples</title>
+   <variablelist>
+     <varlistentry><term><code>apt remove ?garbage</code></term>
+     <listitem><para>Remove all packages that are automatically installed and no longer needed - same as apt autoremove</para></listitem>
+     </varlistentry>
+     <varlistentry><term><code>apt purge ?config-files</code></term>
+     <listitem><para>Purge all packages that only have configuration files left</para></listitem>
+     </varlistentry>
+   </variablelist>
+ </refsect1>
+
+ <refsect1><title>Migrating from aptitude</title>
+   <para>
+   Patterns in apt are heavily inspired by patterns in aptitude, but with some tweaks:
+   </para>
+   <itemizedlist>
+      <listitem>
+         <para>Only long forms &mdash; the ones starting with ? &mdash; are supported</para>
+      </listitem>
+      <listitem>
+         <para>
+            Syntax is uniform: If there is an opening parenthesis after a term, it is always assumed to be the beginning of an argument list.
+         </para>
+         <para>
+            In aptitude, a syntactic form <code>"?foo(bar)"</code> could mean <code>"?and(?foo,bar)"</code> if foo does not take an argument. In APT, this will cause an error.
+         </para>
+      </listitem>
+      <listitem>
+         <para>Not all patterns are supported.</para>
+      </listitem>
+      <listitem>
+         <para>Some additional patterns are available, for example, for finding gstreamer codecs.</para>
+      </listitem>
+      <listitem>
+         <para>Escaping terms with <code>~</code> is not supported.</para>
+      </listitem>
+      <listitem>
+         <para>A trailing comma is allowed in argument lists</para>
+      </listitem>
+   </itemizedlist>
+ </refsect1>
+
+ <refsect1><title>See Also</title>
+   <para>
+   &apt-get;, &apt;
+   </para>
+ </refsect1>
+
+ &manbugs;
+ &manauthor;
+</refentry>
diff --git a/doc/po4a.conf b/doc/po4a.conf
index 587215abc..1cf170b80 100644
--- a/doc/po4a.conf
+++ b/doc/po4a.conf
@@ -30,6 +30,7 @@
 [type: manpage] apt-transport-http.1.xml $lang:$lang/apt-transport-http.$lang.1.xml add_$lang:xml.add
 [type: manpage] apt-transport-https.1.xml $lang:$lang/apt-transport-https.$lang.1.xml add_$lang:xml.add
 [type: manpage] apt-transport-mirror.1.xml $lang:$lang/apt-transport-mirror.$lang.1.xml add_$lang:xml.add
+[type: manpage] apt-patterns.7.xml $lang:$lang/apt-patterns.7.xml add_$lang:xml.add
 
 [type: docbook] guide.dbk $lang:$lang/guide.$lang.dbk
 #                add_$lang::$lang/addendum/docbook_$lang.add
diff --git a/test/integration/test-apt-patterns b/test/integration/test-apt-patterns
new file mode 100755
index 000000000..92c76edd1
--- /dev/null
+++ b/test/integration/test-apt-patterns
@@ -0,0 +1,173 @@
+#!/bin/sh
+TESTDIR="$(readlink -f "$(dirname "$0")")"
+. "$TESTDIR/framework"
+
+setupenvironment
+configarchitecture 'i386' 'amd64'
+
+insertpackage 'unstable' 'available' 'all' '1.0'
+
+insertinstalledpackage 'manual1' 'i386' '1.0' 'Depends: automatic1'
+insertinstalledpackage 'manual2' 'i386' '1.0'
+
+insertinstalledpackage 'automatic1' 'i386' '1.0'
+insertinstalledpackage 'automatic2' 'i386' '1.0'
+
+insertinstalledpackage 'essential' 'i386' '1.0' 'Essential: yes'
+insertinstalledpackage 'conf-only' 'i386' '1.0' '' '' 'deinstall ok config-files'
+insertinstalledpackage 'broken' 'i386' '1.0' 'Depends: does-not-exist'
+
+insertinstalledpackage 'not-obsolete' 'i386' '1.0'
+insertpackage 'unstable' 'not-obsolete' 'all' '2.0'
+
+insertpackage 'unstable' 'foreign' 'amd64' '2.0'
+
+setupaptarchive
+
+testsuccess aptmark auto automatic1 automatic2
+
+msgmsg "Check that commands understand patterns"
+
+testfailureequal "E: input:0-14: error: Unrecognized pattern '?not-a-pattern'
+   ?not-a-pattern
+   ^^^^^^^^^^^^^^
+N: Unable to locate package ?not-a-pattern
+N: Couldn't find any package by glob '?not-a-pattern'
+E: Regex compilation error - Invalid preceding regular expression
+N: Couldn't find any package by regex '?not-a-pattern'
+E: input:0-14: error: Unrecognized pattern '?not-a-pattern'
+   ?not-a-pattern
+   ^^^^^^^^^^^^^^
+N: Unable to locate package ?not-a-pattern
+N: Couldn't find any package by glob '?not-a-pattern'
+E: Regex compilation error - Invalid preceding regular expression
+N: Couldn't find any package by regex '?not-a-pattern'
+E: No packages found" apt show '?not-a-pattern'
+
+testfailureequal "Listing...
+E: input:0-14: error: Unrecognized pattern '?not-a-pattern'
+   ?not-a-pattern
+   ^^^^^^^^^^^^^^" apt list '?not-a-pattern'
+
+testfailureequal "Reading package lists...
+Building dependency tree...
+Reading state information...
+E: input:0-14: error: Unrecognized pattern '?not-a-pattern'
+   ?not-a-pattern
+   ^^^^^^^^^^^^^^
+E: Unable to locate package ?not-a-pattern
+E: Couldn't find any package by glob '?not-a-pattern'
+E: Regex compilation error - Invalid preceding regular expression
+E: Couldn't find any package by regex '?not-a-pattern'" apt install -s '?not-a-pattern'
+
+
+msgmsg "Ensure that argument lists are present where needed, and absent elsewhere"
+
+testfailureequal "Listing...
+E: input:0-7: error: ?true does not expect an argument list
+   ?true()
+   ^^^^^^^"  apt list '?true()'
+testfailureequal "Listing...
+E: input:0-4: error: ?and expects an argument list
+   ?and
+   ^^^^" apt list '?and'
+testfailureequal "Listing...
+E: input:0-3: error: ?or expects an argument list
+   ?or
+   ^^^" apt list '?or'
+
+
+msgmsg "Basic logic: true, false, not, ?or, ?and"
+for pattern in '?true' '?not(?false)'; do
+testsuccessequal "Listing...
+automatic1/now 1.0 i386 [installed,local]
+automatic2/now 1.0 i386 [installed,local]
+available/unstable 1.0 all
+broken/now 1.0 i386 [installed,local]
+conf-only/now 1.0 i386 [residual-config]
+dpkg/now 1.16.2+fake all [installed,local]
+essential/now 1.0 i386 [installed,local]
+foreign/unstable 2.0 amd64
+manual1/now 1.0 i386 [installed,local]
+manual2/now 1.0 i386 [installed,local]
+not-obsolete/unstable 2.0 i386 [upgradable from: 1.0]" apt list "$pattern"
+done
+testsuccessequal "Listing..." apt list '?false'
+testsuccessequal "Listing..." apt list '?not(?true)'
+testsuccessequal "Listing...
+automatic1/now 1.0 i386 [installed,local]
+automatic2/now 1.0 i386 [installed,local]
+manual1/now 1.0 i386 [installed,local]
+manual2/now 1.0 i386 [installed,local]" apt list '?or(?name(^automatic),?name(^manual))'
+testsuccessequal "Listing...
+automatic1/now 1.0 i386 [installed,local]" apt list '?and(?name(^automatic),?name(1$))'
+
+
+msgmsg "Package patterns"
+
+testsuccessequal "Listing...
+foreign/unstable 2.0 amd64" apt list '?architecture(amd64)'
+
+# XXX FIXME We should have support for foreign and native
+testsuccessequal "Listing..." apt list '?architecture(foreign)'
+testsuccessequal "Listing..." apt list '?architecture(native)'
+
+testsuccessequal "Listing...
+automatic1/now 1.0 i386 [installed,local]
+automatic2/now 1.0 i386 [installed,local]" apt list '?automatic'
+
+testsuccessequal "Listing...
+broken/now 1.0 i386 [installed,local]" apt list '?broken'
+
+testsuccessequal "Listing...
+conf-only/now 1.0 i386 [residual-config]" apt list '?config-files'
+
+testsuccessequal "Listing...
+essential/now 1.0 i386 [installed,local]" apt list '?essential'
+
+testsuccessequal "Listing..." apt list '?exact-name(automatic)'
+testsuccessequal "Listing...
+automatic1/now 1.0 i386 [installed,local]" apt list '?exact-name(automatic1)'
+
+testsuccessequal "Listing...
+automatic2/now 1.0 i386 [installed,local]" apt list '?garbage'
+
+testsuccessequal "Listing...
+automatic1/now 1.0 i386 [installed,local]
+automatic2/now 1.0 i386 [installed,local]
+broken/now 1.0 i386 [installed,local]
+dpkg/now 1.16.2+fake all [installed,local]
+essential/now 1.0 i386 [installed,local]
+manual1/now 1.0 i386 [installed,local]
+manual2/now 1.0 i386 [installed,local]
+not-obsolete/unstable 2.0 i386 [upgradable from: 1.0]" apt list '?installed'
+
+testsuccessequal "Listing...
+available/unstable 1.0 all
+conf-only/now 1.0 i386 [residual-config]
+foreign/unstable 2.0 amd64" apt list '?not(?installed)'
+
+testsuccessequal "Listing...
+automatic1/now 1.0 i386 [installed,local]
+automatic2/now 1.0 i386 [installed,local]" apt list '?name(^automatic)'
+
+testsuccessequal "Listing...
+available/unstable 1.0 all
+conf-only/now 1.0 i386 [residual-config]
+foreign/unstable 2.0 amd64
+not-obsolete/unstable 2.0 i386 [upgradable from: 1.0]" apt list '?not(?obsolete)'
+
+testsuccessequal "Listing...
+not-obsolete/unstable 2.0 i386 [upgradable from: 1.0]
+N: There is 1 additional version. Please use the '-a' switch to see it" apt list '?upgradable'
+
+testsuccessequal "Package: does-not-exist
+State: not a real package (virtual)
+N: Can't select candidate version from package does-not-exist as it has no candidate
+N: Can't select versions from package 'does-not-exist' as it is purely virtual
+N: No packages found" apt show '?virtual'
+
+testsuccessequal "Listing..." apt list '?x-name-fnmatch(1)'
+testsuccessequal "Listing...
+automatic1/now 1.0 i386 [installed,local]
+manual1/now 1.0 i386 [installed,local]" apt list '?x-name-fnmatch(*1)'
diff --git a/test/libapt/pattern_test.cc b/test/libapt/pattern_test.cc
new file mode 100644
index 000000000..de2fbceb9
--- /dev/null
+++ b/test/libapt/pattern_test.cc
@@ -0,0 +1,95 @@
+/*
+ * cachefilter-patterns.h - Pattern parser and additional patterns as matchers
+ *
+ * Copyright (c) 2019 Canonical Ltd
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <config.h>
+#include <apt-pkg/cachefilter-patterns.h>
+#include <apt-pkg/cachefilter.h>
+
+#include <gtest/gtest.h>
+
+using namespace APT::Internal;
+
+TEST(TreeParserTest, ParseWord)
+{
+   auto node = PatternTreeParser("word").parseTop();
+   auto wordNode = dynamic_cast<PatternTreeParser::WordNode *>(node.get());
+
+   EXPECT_EQ(node.get(), wordNode);
+   EXPECT_EQ(wordNode->word, "word");
+}
+
+TEST(TreeParserTest, ParseQuotedWord)
+{
+   auto node = PatternTreeParser("\"a word\"").parseTop();
+   auto wordNode = dynamic_cast<PatternTreeParser::WordNode *>(node.get());
+
+   EXPECT_EQ(node.get(), wordNode);
+   EXPECT_EQ(wordNode->word, "a word");
+}
+
+TEST(TreeParserTest, ParsePattern)
+{
+   auto node = PatternTreeParser("?hello").parseTop();
+   auto patternNode = dynamic_cast<PatternTreeParser::PatternNode *>(node.get());
+
+   EXPECT_EQ(node.get(), patternNode);
+   EXPECT_EQ(patternNode->term, "?hello");
+   EXPECT_TRUE(patternNode->arguments.empty());
+   EXPECT_FALSE(patternNode->haveArgumentList);
+}
+
+TEST(TreeParserTest, ParseWithEmptyArgs)
+{
+   auto node = PatternTreeParser("?hello()").parseTop();
+   auto patternNode = dynamic_cast<PatternTreeParser::PatternNode *>(node.get());
+
+   EXPECT_EQ(node.get(), patternNode);
+   EXPECT_EQ(patternNode->term, "?hello");
+   EXPECT_TRUE(patternNode->arguments.empty());
+   EXPECT_TRUE(patternNode->haveArgumentList);
+}
+
+TEST(TreeParserTest, ParseWithOneArgs)
+{
+   auto node = PatternTreeParser("?hello(foo)").parseTop();
+   auto patternNode = dynamic_cast<PatternTreeParser::PatternNode *>(node.get());
+
+   EXPECT_EQ(node.get(), patternNode);
+   EXPECT_EQ(patternNode->term, "?hello");
+   EXPECT_EQ(1u, patternNode->arguments.size());
+}
+
+TEST(TreeParserTest, ParseWithManyArgs)
+{
+   auto node = PatternTreeParser("?hello(foo,bar)").parseTop();
+   auto patternNode = dynamic_cast<PatternTreeParser::PatternNode *>(node.get());
+
+   EXPECT_EQ(node.get(), patternNode);
+   EXPECT_EQ(patternNode->term, "?hello");
+   EXPECT_EQ(2u, patternNode->arguments.size());
+}
+
+TEST(TreeParserTest, ParseWithManyArgsWithSpaces)
+{
+   auto node = PatternTreeParser("?hello (foo, bar)").parseTop();
+   auto patternNode = dynamic_cast<PatternTreeParser::PatternNode *>(node.get());
+
+   EXPECT_EQ(node.get(), patternNode);
+   EXPECT_EQ(patternNode->term, "?hello");
+   EXPECT_EQ(2u, patternNode->arguments.size());
+}
+
+TEST(TreeParserTest, ParseWithManyArgsWithSpacesWithTrailingComma)
+{
+   auto node = PatternTreeParser("?hello (foo, bar,)").parseTop();
+   auto patternNode = dynamic_cast<PatternTreeParser::PatternNode *>(node.get());
+
+   EXPECT_EQ(node.get(), patternNode);
+   EXPECT_EQ(patternNode->term, "?hello");
+   EXPECT_EQ(2u, patternNode->arguments.size());
+}