Initial regression test facility for core diff algorithms

* tests/data/test-core-diff/report0.txt: New test reference data.
	* tests/data/test-core-diff/report1.txt: Likewise.
	* tests/data/test-core-diff/report2.txt: Likewise.
	* tests/data/test-core-diff/report3.txt: Likewise.
	* tests/data/test-core-diff/report4.txt: Likewise.
	* tests/data/test-core-diff/report5.txt: Likewise.
	* tests/test-core-diff.cc: New regression test program.
	* tests/Makefile.am: Add these new files to the build system.

Signed-off-by: Dodji Seketeli <dodji@redhat.com>

tests/Makefile.am

@@ -1,9 +1,10 @@
 h=$(abs_srcdir)
 
-TESTS=				 \
-runtestreadwrite		 \
-runtestwritereadarchive		 \
-runtestsvg			 \
+TESTS=				\
+runtestreadwrite		\
+runtestwritereadarchive		\
+runtestcorediff			\
+runtestsvg			\
 runtestdot 
 
 noinst_PROGRAMS= $(TESTS) testwalker testdiff2
@@ -22,13 +23,17 @@ libtestutils_la_CXXFLAGS=		\
 -DABIGAIL_BUILD_DIR=\"${abs_top_builddir}\"
 
 runtestreadwrite_SOURCES=$(h)/test-read-write.cc
-runtestreadwrite_LDADD= libtestutils.la $(top_builddir)/src/libabigail.la
+runtestreadwrite_LDADD=libtestutils.la $(top_builddir)/src/libabigail.la
 runtestreadwrite_DEPENDENCIES = libtestutils.la
 
 runtestwritereadarchive_SOURCES=$(h)/test-write-read-archive.cc
 runtestwritereadarchive_LDADD= libtestutils.la $(top_builddir)/src/libabigail.la $(top_builddir)/tools/libtoolsutils.la
 runtestwritereadarchive_DEPENDENCIES = libtestutils.la
 
+runtestcorediff_SOURCES=$(h)/test-core-diff.cc
+runtestcorediff_LDADD=libtestutils.la $(top_builddir)/src/libabigail.la
+runtestcorediff_DEPENDENCIES=libtestutils.la
+
 runtestsvg_SOURCES=$(h)/test-svg.cc
 runtestsvg_LDADD=$(top_builddir)/src/libabigail.la
 

tests/data/test-core-diff/report0.txt

@@ -0,0 +1,10 @@
+3 deletions:
+	 happened at indexes: 0 (a), 2 (c), 5 (b)
+
+2 insertions:
+	 after index of first sequence: 0 (a)
+		 inserted indexes from second sequence: 0 (c)
+	 after index of first sequence: 6 (a)
+		 inserted indexes from second sequence: 5 (c)
+
+

tests/data/test-core-diff/report1.txt

@@ -0,0 +1,6 @@
+3 deletions:
+	 happened at indexes: 0 (x), 2 (a), 5 (x)
+
+no insertion
+
+

tests/data/test-core-diff/report2.txt

@@ -0,0 +1,8 @@
+3 deletions:
+	 happened at indexes: 0 (x), 2 (a), 5 (x)
+
+1 insertion
+	 after index of first sequence: 3 (b)
+		 inserted indexes from second sequence: 2 (c)
+
+

tests/data/test-core-diff/report3.txt

@@ -0,0 +1,11 @@
+no deletion:
+1 deletion:
+
+
+5 insertions:
+	 after index of first sequence: 1 (b)
+		 inserted indexes from second sequence: 2 (d), 3 (e)
+	 after index of first sequence: 2 (c)
+		 inserted indexes from second sequence: 5 (f), 6 (g), 7 (c)
+
+

tests/data/test-core-diff/report4.txt

@@ -0,0 +1,7 @@
+no deletion:
+1 deletion:
+
+
+no insertion
+
+

tests/data/test-core-diff/report5.txt

@@ -0,0 +1,6 @@
+1 deletion:
+1 (a)
+
+no insertion
+
+

tests/test-core-diff.cc

@@ -0,0 +1,143 @@
+// -*- Mode: C++ -*-
+
+// Copyright (C) 2013 Red Hat, Inc.
+//
+// This file is part of the GNU Application Binary Interface Generic
+// Analysis and Instrumentation Library (libabigail).  This library is
+// free software; you can redistribute it and/or modify it under the
+// terms of the GNU Lesser General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option) any
+// later version.
+
+// This library is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// General Lesser Public License for more details.
+
+// You should have received a copy of the GNU Lesser General Public
+// License along with this program; see the file COPYING-LGPLV3.  If
+// not, see <http://www.gnu.org/licenses/>.
+//
+// Author: Dodji Seketeli
+
+#include <string>
+#include <fstream>
+#include <iostream>
+#include <cstdlib>
+#include "abg-tools-utils.h"
+#include "abg-diff-utils.h"
+#include "test-utils.h"
+
+using std::string;
+using std::ofstream;
+using std::cerr;
+
+/// This structure describes the set of strings we want to diff
+/// against each other as well as the reports we expect from these
+/// diffs.
+struct SESInOutSpec
+{
+  // This is the path to the report we expect from the diff algorithm
+  // applied to second_string (below) diffed against first_string.
+  const char* in_path;
+  // This is the path where to store the report of the diff algorithm
+  // applied to second_string (below) diffed against first_string.
+  const char* out_path;
+  // This is the first string to feed the diff algorithm with.
+  const char* first_string;
+  // This is the second string to feed the diff algorithm with.
+  const char* second_string;
+};// end struct SESInOutSpec
+
+SESInOutSpec in_out_specs[] =
+{
+  {
+    "data/test-core-diff/report0.txt",
+    "output/test-core-diff/report0.txt",
+    "abcabba",
+    "cbabac"
+  },
+  {
+    "data/test-core-diff/report1.txt",
+    "output/test-core-diff/report1.txt",
+    "xxabxx",
+    "xbx"
+  },
+  {
+    "data/test-core-diff/report2.txt",
+    "output/test-core-diff/report2.txt",
+    "xxabxx",
+    "xbcx"
+  },
+  {
+    "data/test-core-diff/report3.txt",
+    "output/test-core-diff/report3.txt",
+    "abc",
+    "abdecfgc"
+  },
+  {
+    "data/test-core-diff/report4.txt",
+    "output/test-core-diff/report4.txt",
+    "xxx",
+    "xxx"
+  },
+  {
+    "data/test-core-diff/report5.txt",
+    "output/test-core-diff/report5.txt",
+    "xabx",
+    "xbx"
+  },
+  // This should be the last entry.
+  {NULL, NULL, NULL, NULL}
+};
+
+using abigail::diff_utils::edit_script;
+using abigail::diff_utils::compute_ses;
+using abigail::diff_utils::display_edit_script;
+
+int
+main()
+{
+  unsigned result = 1;
+
+  bool problem = false;
+  string in_path, out_path;
+
+  for (SESInOutSpec *s = in_out_specs; s->in_path; ++s)
+    {
+      string input_suffix(s->in_path);
+      in_path = abigail::tests::get_src_dir() + "/tests/" + input_suffix;
+
+      string output_suffix(s->out_path);
+      out_path = abigail::tests::get_build_dir() + "/tests/" + output_suffix;
+
+      if (!abigail::tools::ensure_parent_dir_created(out_path))
+	{
+	  cerr << "Could not create parent director for " << out_path;
+	  problem = true;
+	  return result;
+	}
+
+      ofstream of(out_path.c_str(), std::ios_base::trunc);
+      if (!of.is_open())
+	{
+	  cerr << "failed to read " << out_path << "\n";
+	  problem = true;
+	  continue;
+	}
+
+      edit_script ses;
+      // Compute the Shortest Edit Script (aka diff) that changes
+      // s->first_string into s->second_string.
+      compute_ses(s->first_string, s->second_string, ses);
+      // Emit a report about that edit script
+      display_edit_script(ses, s->first_string, s->second_string, of);
+      of.close();
+      // Diff that report against what we expect.
+      string cmd = "diff -u " + in_path + " " + out_path;
+      if (system(cmd.c_str()))
+	problem= true;
+    }
+
+  return problem;
+}